fact not fiction. science not speculation.inside a hi-tech uav powerplant real-time operating...

Space systemsThe ExoMars autonomous mission

Ultralight rotary powerAustro Engine’s aero solution

Cable assemblyAdvanced wiring analysed

Autonomous miningWhat’s driving the technology?

Autopilot systemsLeading the way

Batteries and chargersDevelopments in portable power

USV technologyUnder the skin of surface craft

Delair-Tech DT18Flying beyond the line of sight

UST 04 : AUTUMN/FALL 2015

UK £15, USA $30, EUROPE e22

UST 02 : SPRING 2015


The all-seeing eyeState-of-the-art vision sensors for unmanned craft

Driverless 4WDMIRA’s autonomous Land Rover

Danielson dieselInside the new generation Scion

SA-400Autonomous helicopter technology

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LAUNCH ISSUE : NOVEMBER 2014


Hirth’s two-stroke magicInside a hi-tech UAV powerplant

Real-time operating systemsAnalysing the development issues

Penguin UAV DossierSecrets of a record-breaking platform revealed

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01 UST Cover 2.indd 3 01/10/2014 20:53

Fact not fiction. Science not speculation.

2016 EURe media kit

Published by




















01 UST Cover 2.indd 3 01/10/2014 20:53

www.highpowermedia.com

Platform one

The UST news section is focused on technologicaldevelopment. Business and politics are only covered in so far as they impact directly on engineering solutions. From the outset UST has established itself as a publication that deals in hard science.

UST insights

UST ‘Insights’ drill down into specific technological topicsand unmanned vehicle applications. Each issue will carry one insight on an application of unmanned systems – from the bottom of the oceans to the far reaches of outer space. We will cover all areas during the year, culminating in an overview of the latest tech trends at the end of the year. UST is dedicated to providing invaluable knowledge for engineers.

Unmanned vehicle dossiers

Each issue of UST contains a main ‘Dossier’ offering an incredibly detailed look at a high-profile unmanned vehicle project, revealing many secrets of the technology that are simply not reported anywhere else.

Engine dossiers

The world of unmanned systems has created new requirements for small internal combustion engines, to the extent that currently there is far from agreement as to the most appropriate technical solution. A host of different approaches are being exploited, from two-stroke to four-stroke, from jet fuel to gasoline and from Wankel rotary to reciprocating. Each of UST’s Engine Dossiers explores in depth one of the diverse innovative power plants at the forefront of today’s unmanned revolution.

UST is unique – launched in October 2014, UST is the first ever publication to focus entirely on providing independent coverage of the engineering at the heart of unmanned systems. Published bi-monthly in 2016, it probes today’s cutting-edge projects to provide in-depth research insights, using rigorous investigation backed by professional peer review and critical analysis.

The unmanned systems industry is projected to grow exponentially over the coming years. UST is an invaluable resource of actionable intelligence for engineers whilst also providing a targeted promotional platform for those with products and services of interest to them. If you want to seize more than your fair share of the fresh opportunities being created in this exciting sphere then UST is an absolute must.







01 UST Cover 2.indd 3 01/10/2014 20:53








76

Solid hydrogen storage pellets and fuel

cell technology are set to significantly

increase the flight duration potential of

electric UAVs.

Consider, for example, AeroVironment’s

Raven RQ-11, a UAV widely used for

reconnaissance by the US military

and other operators worldwide. Hand

launched, it has a 1.37 m wingspan

and weighs just under 2 kg, carrying a

surveillance camera and motor powered

by a lithium-ion battery giving it an

endurance of 60-90 minutes. Replacing

the battery with a pellet-fed hydrogen fuel

cell promises to triple its endurance.

The pellets have been developed by

Cella Energy, which has been working

with systems integrator L2 Aerospace

to replace the battery in a Raven with a

How difficult is fuel flow measurement?

The answer clearly depends on the

required accuracy.

In internal combustion engine test cells,

fuel flow is traditionally measured with

an extremely high degree of accuracy

using a Coriolis-type meter. In the context

of a UAV though, that is impractical, not

only because of the weight of such a

meter but its size – which is as large as a

bathroom cabinet.

The challenge then is to develop an

alternative means of measurement that

is feasible within the confines of a small

UAV, without significantly affecting the

craft’s weight. After all, the whole point

of precise fuel measurement in this

context is to allow the craft to exploit the

maximum flying time it can obtain from

its fuel load. Clearly, that task is complex

and challenging.

UAV internal combustion engines

are typically small-displacement two-

strokes, sometimes using a carburettor

but more often nowadays equipped with

electronically controlled fuel injection,

under the command of an ECU. It is

quite normal for that ECU to incorporate

data logging and to send that data to

the operator; from the logging of injector

opening times, most systems will calculate

fuel consumption. That’s all well and good

but how accurate is such measurement?

far greater source of electrical power for

comparable weight. There is wide interest

in proving the technology for the growing

number of civilian and commercial

applications, as it can be applied to

all electric-powered unmanned craft.

To this end, Cella is part of a further

collaboration, co-funded by the UK’s

innovation agency, Innovate UK, to

develop a 200 W hydrogen system for a

larger unmanned marine survey aircraft

used by the Scottish Association for

Marine Science, with fuel cell integration

by Arcola Energy. A test flight is planned

by summer 2015.

Central to the concept is the use

of the pellets instead of a tank of

hydrogen to supply the fuel cell. Cella

Energy’s pellets are solid capsules

that combine ammonia borane and a

The answer depends on the approach

to it. Using sophisticated techniques,

ECU supplier Performance Electronics

has developed what it says is accurate

fuel flow measurement as a modestly

priced adjunct to its control systems.

Those systems are used in automotive

applications as well as internal

combustion-engined UAVs.

Performance Electronics does a lot of

work for OEMs and others, supplying

engine control components with

branding by the customer; however, it

also offers its own brand of ECU, a multi-

purpose unit that incorporates ignition

coil and injector drivers, offers other

outputs according to the specific version,

accepts readings from all necessary

engine sensors and has a diagnostics

capability via CAN together with data

acquisition. It can be mapped using a PC

in the normal manner.

UAV versions of this control unit – the

PE4 – use similar hardware and firmware

modules as automotive versions, and

similar tuning software. The PE4 is fully

configurable and adaptable to specific

applications. Performance Electronics

engineer Brian Lewis noted that, for

example, some UAV applications require

more thermocouples than others.

“We have a daughterboard that can

accommodate that and lots of other

custom requirements. We also offer

polymer, and which release hydrogen

gas when heated to 100 C. Whereas

hydrogen gas normally has to be

compressed and consequently stored

in a strong and hence heavy tank, the

pellets can be stored on the craft in an

easily replaceable cartridge at ambient

pressure and temperature.

The pellets are heated sequentially

throughout a mission as dictated by the

UAV’s electronic control system, so as to

provide a constant supply of hydrogen

from this wing structure location to the

fuel cell. Only a few per cent of the total

energy output of the fuel cell is needed to

heat the pellets. The net result is a system

that can match the weight of the normal

lithium-ion battery while promising

sufficient energy to keep the motor

running for up to three times longer.

options such as Mil-spec connectors.”

It is the UAV market that has driven

Performance Electronics’ development

of integral fuel flow measurement. “We

found that our UAV customers wanted

more accurate fuel consumption

calculation,” explained Lewis. “They

wanted to know how much fuel they are

using, so they can work out how long

they can continue to fly.”

Lewis also said that in its own right

fuel injector opening time as set by

the injector drivers within the ECU is

insufficient data from which to accurately

calculate consumption, even when

referenced to fuel pressure, engine speed

and the prevailing mapping. The injector

dynamics have to be understood, starting

with the calibration of each injector with

reference even to battery condition.

He noted that it often isn’t appreciated

that battery voltage compensation is a

vital aspect of injector driving. “The ECU

can only alter mass flow indirectly via the

injector open time, and if battery voltage

isn’t what it thinks it is then a required,

10% change in mass flow for example

might in reality be a 15% change.”

Thus it is that an appreciation of

actual injector dynamics is central

to Performance Electronics’ fuel flow

measurement, which can be incorporated

into closed-loop control of an engine run

by one of its units.

76

Mission-critical info for UST professionals

Platform one

The pros of pellets

Cella Energy scientists working on the hydrogen-powered Raven UAV

This new NW-44 multi-fuel UAV engine produced by Northwest UAV is using Performance Electronics’ ECU with fuel measurement technology

Power supply

Going with the flowFuel management

November 2014 | Unmanned Systems Technology Unmanned Systems Technology | November 2014

Platform one

4948

Danielson Aircraft Systems

(DAS) is part of the Groupe

Danielson organisation

based beside the Magny

Cours (former Grand Prix)

circuit in France, and well known in the

automotive world for its road engines.

Danielson has enormous depth of

experience of compression-ignition (CI)

engines, so popular with French car

manufacturers. That experience, and its

increasing involvement in aerospace,

led to the French military commissioning

it to develop a clean-sheet-of-paper

turbodiesel specifically for UAV use.

Following that commission DAS now

has a range of three Trident engines,

of which the initial inline three-cylinder

(I3) 100 TD2 customer unit is profiled

here. The director of DAS, Frederic

Hubschwerlen, says the Trident project

was specifically targeted at the UAV

market rather than general aviation.

The customer Trident was developed

as a complete package with all ancillaries

including the cooling system and

transmission through to the propeller. The

state-of-the-art 100 TD2 is a 1.1 litre I3 that

features two-stage turbo-supercharging

yet has a dry weight of only 70 kg. It

runs on regular diesel or heavy fuel

and exploits mechanical rather than

electronic injection to keep it free from

electromagnetic interference. Among its

innovations is a novel torque-smoothing

system to protect the transmission.

Everything for the project was designed

in-house at DAS, whose extensive

manufacturing capability meant that very

little component production had to be

outsourced. Although Groupe Danielson

has extensive CI experience, it didn’t

follow that the Trident engines had to

be turbodiesels; they could have been

spark ignition (SI) like many existing UAV

engines. The design team saw a number

of advantages from the use of CI.

Regardless of power level – and Trident

is catering for 100 to 180 bhp – the

top priority in the UAV market is flight

time. In this respect CI is theoretically

advantageous compared with SI, since it

is inherently more fuel-efficient. A higher

compression ratio and a lack of throttling

of the charge air are, on paper, the basis of

efficiency higher than that of a comparable

SI engine. The main inherent drawback of

a CI engine though is lack of valve overlap

to assist charging, but that is counteracted

by the use of turbo-supercharging.

The CI process does reduce the time

available for injection, but that isn’t such

an issue given a combination of forced

induction and a correspondingly reduced

engine speed. That in turn (due to the

relatively low crankshaft speed) implies

reduced frictional losses, while the

relatively high compression ratio and the

use of turbocharging imply high torque.

The only real downside is the structural

requirement caused by the associated

elevated cylinder pressures, which

can result in a weighty engine, but

Danielson’s expertise with in-house

aluminium and magnesium castings has

paid dividends here.

Although mechanically injected, the

Trident family exploits direct injection

into the combustion chamber, reflecting

state-of-the-art CI practice. Also, CI

lends itself to the use of heavy fuels:

kerosene (paraffin) based fuels are

widely used by armed forces. They are

less flammable than gasoline, and so

are better suited to CI rather than SI.

The exhaust temperature of a CI

engine is inherently lower than that of an

SI one due to a higher expansion ratio.

On top of that, the 100 TD2’s dual-stage

turbocharging system further reduces

the acoustic and thermal signatures of

the exhaust – important considerations

for many UAV operators. Most important

of all though is flight time, and

Hubschwerlen says the Tridents have

been measured by DAS to be 40% more

fuel-efficient than a UAV four-stroke SI

engine of the same power level.

He also reports that the Trident project

was a response to specific issues

encountered by the French military in

operating its UAVs, identified as fuel

injection problems, acoustic signature

concerns, rapid wear, complexity of

maintenance, high fuel consumption,

high total ownership cost and operational

risks. All of these were associated

with the existing propulsion system

the military used, which had not been

designed for requirements such as high-

altitude operation, extreme temperatures

and high operational availability.

Trident is designed to address those

issues, exploiting proven Danielson

technology in a package designed

specifically for UAV requirements, in

particular exploiting a range of fuel

chemistries. In general terms, kerosene-

based fuels ignite quicker than diesel,

calling for appropriate adjustment

Danielson Aircraft Systems Trident 100 TD2 turbodiesel | Dossier

Ian Bamsey investigates a state-of-the-art French turbodiesel that’s been created specifically for UAV use

Spring 2015 | Unmanned Systems Technology Unmanned Systems Technology | Spring 2015

Three-pronged attack

Cutaway of Danielson’s Trident, three-cylinder turbodieselCompact turbodiesel power – the Danielson Trident 100 TD2

The Trident project was a response to issues the French military had with operating its UAVs such as fuel injection problems and high total ownership costs

4544

Google’s acquisition of

Titan Aerospace and its

‘atmospheric satellite’

has placed more

emphasis on the power

requirements of autonomous vehicles.

The prospect of using such solar-

powered craft instead of a satellite to host

a wireless service to deliver the internet

to PCs and phones in areas without

data coverage presents some very real

engineering challenges.

An example of the challenges comes

from the 2.5 m wingspan Green Falcon

UAV developed at the Queensland

University of Technology in Australia. This

is powered by 28 monocrystalline solar

cells generating just 500 mW, but that

is enough to power its electric engine,

onboard cameras and sensors to track

the progress of bushfires.

Larger, High Altitude Long Endurance

(HALE) UAVs can use the increased

surface area of their wings to generate

more power from solar cells to run their

propulsion and payload systems – which,

when the payload is a cellular base

station, is a serious challenge that is still

in the research lab.

Titan, based in New Mexico, has

developed the Solara 50, which is 15.5 m

(54 ft) long with a wingspan of 50 m

and carries a payload of 32 kg (70 lb).

It is powered by 3000 solar cells across

the upper wing, elevator and horizontal

stabiliser to provide up to 7 kW, storing

any excess in lithium-ion batteries in

the wings. Lithium-sulphur rechargeable

batteries provide an energy density of

400 Wh/kg while normal lithium-polymer

batteries provide 200 Wh/kg

The combination of the solar cells and

the lithium-sulphur batteries provides

enough power to keep the UAV in the

air for months, say the designers, at a

cruising altitude of 20 km (65,000 ft) as

The third-party autopilot software in

the Solara 50 is modelled by Google

engineers in the Matlab and Simulink

development tools, with the ability to add

extensions to enhance the requirements

of a specific operation. This takes into

account the advantage that, by loitering

on-station or circling over an area at high

altitude, the system will have a line-of-sight

connection to provide the best possible

link without having to worry about multi-

path interference or any signal degradation

as it passes through floors and walls.

A base station could be designed to fit

into the Solara’s 32 kg payload, but since

the propulsion system is a 5.5 kW electric

motor, that would leave only 1.5 kW for

other activities. Reducing the weight and

increasing the efficiency of the motor so

that it uses less power would deliver more

power for communications. A larger version,

the Solara 60, will be 60 m (197 ft) across

with a boost to 8 kW of power from more

an airborne communications station,

and eventually up to five years flying at

65 mph. This speed is determined by

the average wind speed of just 15 mph

at that altitude, coupled with the lower

air density, which means the craft has to

travel three times faster than closer to the

ground to maintain its lift.

These capabilities appealed to Google,

which bought the company in April 2014

to be part of its Google X technology

r&d lab. Solara could potentially replace

the balloon-based systems that Google

has been testing out, but the power

generated from the cells is the crucial

engineering constraint.

The Solara 50 uses a third-party fixed-

wing autopilot that has been integrated

with a GPS navigation system to enable

it to fly, take off and land autonomously,

and alongside various onboard sensors

in the payload it also has high-speed

radio links for transmitting telemetry data

solar cells on its surface, and an increased

payload of up to 100 kg (250 lb).

The actual base station technology

is still to be determined, but it will need

to provide a balance between available

technology, the power available –

known as the power budget – and the

availability of PCs or phones to connect

to the internet. Mobile phones are

designed to receive signals down to

-135 dBm, but have limits on the

bandwidth they can support. Wi-fi is also

widely available on handsets and on

every laptop PC, and could be teamed

with access points on the ground to

provide local networks and reduce the

load on the base station.

Airborne base stations | Insight

Aiming for the high life

UAVs look set to take on a key role as communications base stations – once various engineering challenges have been overcome. Nick Flaherty reports

back to the ground station. The autopilot

software, which is used by other UAV

companies such as NVOS, in Virginia in

the US, handles airspeed, altitude, pitch,

roll, heading or turn rate, and includes an

‘autonomous loiter’ function. This allows

the aircraft to remain at a fixed altitude

and position, or to return to ‘home’ and

loiter. In loiter mode, the UAV faces into

the wind, drifts with it for a short distance

and then powers up to return to the loiter

location.

This is vital, as it maximises duration by

minimising the power required to remain

at a constant location. At no point does

it turn downwind, as this would result in

it having to expend too much energy to

compensate.

The autopilot also handles landing

consistently on a narrow runway, even

in a crosswind, by intelligently managing

landing pattern and glideslope to

minimise over- or undershoot.

The large arrays of solar cells on its 50 m wings and the tail are the key to powering the Solara 50


Wiring harnesses are the nerves of unmanned craft (Courtesy of St Cross Electronics)

3332

One of the core challenges

with an unmanned

system is the connectivity

needed inside the

vehicle which, given

the number and variety of sensors

and cameras being used in them,

brings with it an increased need for

communications and therefore power.

Also, instead of having a centralised

control cockpit laid out around a driver

or pilot, unmanned systems have a

much more distributed design, and this

is changing the way the cable harness

that supplies power and data around the

vehicle is designed and implemented.

This is a key element in the challenge

to reduce SWaP – Size, Weight and

Power – in unmanned systems. Less

weight means a longer range for UAVs

and driverless cars, while a smaller size

for the electronics means more space

for passengers or for larger batteries,

and the harness can take up a surprising

amount of weight.

There are many ways of delivering data

around an unmanned system. Traditional

harness designs use copper wires, but

optical fibres and even wireless links can

be used. Each of these technologies has

its challenges, but the fundamental issue

for all of them is the need to provide

power as well. Every sensor and actuator

in the vehicle needs power, and has to

deliver data back to a control unit, so the

traditional approach has been to provide

that power alongside the signals by using

separate copper cables.

In every unmanned systems market

the proliferation of sensors, telemetry and

comms – and their distribution around

the vehicle – severely restricts system

weight and size, so the lighter, smaller and

faster you can make the connectivity then

the better the platform is able to perform.

However, with new high-speed connection

protocols such as HDMI being used for

high-resolution cameras, the range of

connectivity requirements is continuously

growing. This gives the harness designer

and maker more challenges, and

highlights the separation between the

power and comms functions.

To build a harness, cables of different

thicknesses can be woven together

into a ribbon, with the thicker cables

delivering power and the thinner cables

carrying signals. The thousands of

cables required in a vehicle constitute

considerable weight and cost, however,

and while some harness makers are

starting to use aluminium rather than

copper to reduce the weight, there is also

a move to adopting different approaches

for connecting sensor units (see below).

Some unmanned systems are

able to challenge the existing design

methodologies. For example, having

solar panels on the wings and body

of a UAV allows power to be provided

closer to the sensors and actuators. This

removes the need for distributed power

cabling around the craft, potentially

reducing the complexity and weight of

the harness. However, the trade-off is

that more power management devices

have to be distributed around the craft.

This highlights the need for the harness

to be an integral part of the design of the

system, and for different architectures

to be assessed to provide the optimum

design with minimum weight.

Cabling There are various ways to build a

conventional harness, ranging from

bundling a set of wires together to

weaving them together. Cables have

been woven into ribbons for more than

45 years, but like everything else in the

modern world the harness has evolved

over that time.

At the moment, developers tend to

build a system and hang a harness

on it afterwards; going forward though,

harness makers will need to provide the

interconnectivity wherever it is needed

throughout the unmanned system. This

means that the design and project

managers can rethink wiring systems

away from conventional approaches and

integrate new methods (see below) into

their products that allow them to build

lighter systems with higher performance.

Very often the conventional harnesses

limit the design of an unmanned craft.

There are existing specifications and

conventions for the interconnections that

have been used for many years, and it

takes a brave engineer to adopt a new way

of implementing these connections instead

of something they’ve used for 20 years.

Now though, using wires as small

as 44 AWG allows a ribbon cable

only 9.5 mm wide to be built with 50

twisted pairs which provides substantial

signal connectivity. Many spacecraft

have these ribbons on either the flight

harnesses or in the instrumentation

packages and experiments.

A newer approach is to put these

ribbons inside a jacket or shell. One

application of this is to provide power for

de-icing the rotor blades of a helicopter,

and essentially these aren’t a harness

any more, but shaped components

accurate to +/- 1.00 mm with clamps and

pads built in and made from a 3D model.

This application is one of the harshest

environments an interconnection system

can work in.

The choice of shell or jacket materials

depends on the application, and typical

materials include polyurethane and

epoxy. It is possible to put 50 conductors

in a ribbon within a structure that’s 1 mm

thick and 19 mm wide; these are still built

as an add-on harness, but with UAVs in

particular the aim would be to lay the

ribbons into the airframe structure. Using

44 AWG wire to carry signals in the

Cable harnesses | Focus

Harness designs have traditionally used copper wires but optical fibres and even wireless links can be used. Each type though has its challenges

Summer 2015 | Unmanned Systems Technology Unmanned Systems Technology | Summer 2015

Well connectedHow do you serve an unmanned system’s need for power and signalling while keeping weight, space and cost to a minimum? Nick Flaherty reports

Weaving cables into a ribbon for a harness (Courtesy of Tekdata)












www.unmannedsystemstechnology.com

Focus articles

Revisited just once every 2-3 years the ‘Focus’ acts as an excellent source of reference on specific products and types of engineering service – topics covered include: • Additive Layer Manufacturing • Advanced Metals • Ancillary engine systems • Antenna systems • Autopilot/Flight controllers • Batteries • Cameras/imaging • Coatings • Composites • Connectors • Control systems • Data acquisition • Data storage • Electric motors • Fuel cells • GNSS • GPS • Ground control systems • Hardware • Motion control systems • Propellers • Radio links • RTOS • Sense & avoid • Sensors – electro optic/radar/acoustic • Simulation • Software • Solar power • Sonar/Acoustics • Telemetry • Test equipment • Test facilities • Training • Transmission • Transponders • UAV launch & recovery • Vision sensors • Wiring harnesses/cable assemblies.







4544

Google’s acquisition of

Titan Aerospace and its

‘atmospheric satellite’

has placed more

emphasis on the power

requirements of autonomous vehicles.

The prospect of using such solar-

powered craft instead of a satellite to host

a wireless service to deliver the internet

to PCs and phones in areas without

data coverage presents some very real

engineering challenges.

An example of the challenges comes

from the 2.5 m wingspan Green Falcon

UAV developed at the Queensland

University of Technology in Australia. This

is powered by 28 monocrystalline solar

cells generating just 500 mW, but that

is enough to power its electric engine,

onboard cameras and sensors to track

the progress of bushfires.

Larger, High Altitude Long Endurance

(HALE) UAVs can use the increased

surface area of their wings to generate

more power from solar cells to run their

propulsion and payload systems – which,

when the payload is a cellular base

station, is a serious challenge that is still

in the research lab.

Titan, based in New Mexico, has

developed the Solara 50, which is 15.5 m

(54 ft) long with a wingspan of 50 m

and carries a payload of 32 kg (70 lb).

It is powered by 3000 solar cells across

the upper wing, elevator and horizontal

stabiliser to provide up to 7 kW, storing

any excess in lithium-ion batteries in

the wings. Lithium-sulphur rechargeable

batteries provide an energy density of

400 Wh/kg while normal lithium-polymer

batteries provide 200 Wh/kg

The combination of the solar cells and

the lithium-sulphur batteries provides

enough power to keep the UAV in the

air for months, say the designers, at a

cruising altitude of 20 km (65,000 ft) as

The third-party autopilot software in

the Solara 50 is modelled by Google

engineers in the Matlab and Simulink

development tools, with the ability to add

extensions to enhance the requirements

of a specific operation. This takes into

account the advantage that, by loitering

on-station or circling over an area at high

altitude, the system will have a line-of-sight

connection to provide the best possible

link without having to worry about multi-

path interference or any signal degradation

as it passes through floors and walls.

A base station could be designed to fit

into the Solara’s 32 kg payload, but since

the propulsion system is a 5.5 kW electric

motor, that would leave only 1.5 kW for

other activities. Reducing the weight and

increasing the efficiency of the motor so

that it uses less power would deliver more

power for communications. A larger version,

the Solara 60, will be 60 m (197 ft) across

with a boost to 8 kW of power from more

an airborne communications station,

and eventually up to five years flying at

65 mph. This speed is determined by

the average wind speed of just 15 mph

at that altitude, coupled with the lower

air density, which means the craft has to

travel three times faster than closer to the

ground to maintain its lift.

These capabilities appealed to Google,

which bought the company in April 2014

to be part of its Google X technology

r&d lab. Solara could potentially replace

the balloon-based systems that Google

has been testing out, but the power

generated from the cells is the crucial

engineering constraint.

The Solara 50 uses a third-party fixed-

wing autopilot that has been integrated

with a GPS navigation system to enable

it to fly, take off and land autonomously,

and alongside various onboard sensors

in the payload it also has high-speed

radio links for transmitting telemetry data

solar cells on its surface, and an increased

payload of up to 100 kg (250 lb).

The actual base station technology

is still to be determined, but it will need

to provide a balance between available

technology, the power available –

known as the power budget – and the

availability of PCs or phones to connect

to the internet. Mobile phones are

designed to receive signals down to

-135 dBm, but have limits on the

bandwidth they can support. Wi-fi is also

widely available on handsets and on

every laptop PC, and could be teamed

with access points on the ground to

provide local networks and reduce the

load on the base station.

Airborne base stations | Insight

Aiming for the high life

UAVs look set to take on a key role as communications base stations – once various engineering challenges have been overcome. Nick Flaherty reports

back to the ground station. The autopilot

software, which is used by other UAV

companies such as NVOS, in Virginia in

the US, handles airspeed, altitude, pitch,

roll, heading or turn rate, and includes an

‘autonomous loiter’ function. This allows

the aircraft to remain at a fixed altitude

and position, or to return to ‘home’ and

loiter. In loiter mode, the UAV faces into

the wind, drifts with it for a short distance

and then powers up to return to the loiter

location.

This is vital, as it maximises duration by

minimising the power required to remain

at a constant location. At no point does

it turn downwind, as this would result in

it having to expend too much energy to

compensate.

The autopilot also handles landing

consistently on a narrow runway, even

in a crosswind, by intelligently managing

landing pattern and glideslope to

minimise over- or undershoot.

The large arrays of solar cells on its 50 m wings and the tail are the key to powering the Solara 50


1918

Scion UAS, based near

Denver in Colorado and co-

located with sister company

Scion Aviation, is developing

a very special helicopter, the

SA-400 Jackal, which can accommodate

one person although they can opt not to

fly it themselves. In fact, that person can

be merely a passenger, with the craft

operating in fully autonomous mode.

Alternatively, it can fly without anyone on

board. Moreover, even flying unmanned,

it can operate from a ship, regardless of

the sea causing the deck to pitch, yaw

and heave.

The SA-400’s origins In 2012, Scion UAS responded to an offer

for tender by the United States Naval

Research Laboratory (NRL), calling for

an unmanned rotorcraft to be used in

its evaluation of specific payloads under

certain arduous conditions. For this

purpose the helicopter the company then

had under development, the SA-200

Weasel, with a length of 89.2 in (227 cm)

and a rotor diameter of 81.5 in (207 cm),

wouldn’t be large enough. More carrying

capability was called for.

The far more powerful SA-400 Jackal

that Scion offered for tender would

be a completely new project, and by

comparison would have a length of

232 in (589 cm) and a rotor diameter

of 250 in (635 cm). It would, however,

exploit the same advanced autonomous

operation technology initially developed

for the compact SA-200.

In the end the SA-400 proposal won

the NRL contract. That was at the end

of September 2012, and the deal was to

supply a pair of SA-400s with the option

for a third after satisfactory trials of the

prototype. In the light of this, the SA-200

project was put on the back burner,

just after its first ground tests had been

carried out, although Scion UAS CEO

Steen Mogensen emphasises that it will

be reactivated this summer, once the

NRL contract has been completed.

The fact that the SA-400 optionally

carries a person and that, if suitably

qualified, they can become its pilot

at the flick of a switch has been very

useful for development. Not only can

they concentrate on monitoring an

autonomous flight, their presence in the

cockpit means the FAA considers it as a

manned craft from the perspective of its

operational regulations, which are much

tougher for unmanned craft. Given that a

pilot is on board, there isn’t the restriction

on the use of commercial airspace

that there would be in the case of an

unmanned craft. The ability to ‘See and

Avoid’ is satisfied by the onboard pilot.

Currently the two initial SA-400s are

flying under an ‘Experimental’ FAA

classification. That is an airworthiness

certificate granted for a specific r&d craft,

accepting that there hasn’t been the

likes of crash testing but acknowledging

that there has been an FAA inspection

of it. Under an Experimental licence the

craft cannot be used for commercial

operations. It can be flown for r&d

purposes, initially within defined

geographic boundaries, but after a

certain number of hours have been

logged then anywhere nationwide.

The capabilities of the SA-400 without

a pilot on board were demonstrated

in September 2014. This exercise,

conducted in restricted airspace,

included autonomous take-off and

landing using a (truck-towed) mobile

platform. The first vehicle was delivered

to the NRL immediately after this

successful demonstration.

Flight trials of the second SA-400

began in early December 2014, the time

of UST’s visit, with delivery scheduled for

early 2015. Scion UAS is offering both

the SA-400 and the SA-200 on the open

market, and in due course it also plans

smaller as well as larger rotorcraft in its

product line-up.

The design briefThe SA-400 was designed to meet a

certain payload capability requirement of

the NRL but was not otherwise tailored

to a specific application; it is suitable for

multiple uses. The NRL requirement

was that it must be capable of carrying

a 100 lb payload for four hours’ flying

Ian Bamsey travels to Scion UAS in Colorado to get the low-down on a helicopter for which the pilot is optional, the SA-400 Jackal


Day of the Jackal

Scion UAS SA-400 optionally piloted helicopter | Dossier

Detail of the SA-400 during assembly, showing the tail rotor drive shaft, the main transmission, pulley with one-way clutch, dual alternators and main (Kevlar) drive belts

An SA-400 in flight – note optional side tank

6160

A composite is essentially

a material or structure

formed of two (possibly

more) distinct elements, the

principle being of course

to counter the disadvantages of the one

with the advantages of the other(s), and

vice versa. In unmanned systems, the

functional engineering objective is most

typically to achieve the best possible

mechanical properties for the least

weight, balanced against other factors

such as transparency to communication/

sensor frequencies, overall cost to

manufacture/maintain, and durability.

The use of composites to achieve these

objectives is a natural solution, as they

often provide superior specific properties

– that is, the strength or stiffness per unit

weight of material – compared to those

of non-composites.

The composites used in unmanned

vehicles can be divided into two basic

groups – metal matrix composites

(MMCs) or polymer matrix composites

(PMCs) – which are then reinforced with

fibres or particles of another material that

is typically more brittle but far stronger

and stiffer than the matrix. In such a

combination, the reinforcing material

carries the loading, while the softer matrix

serves to protect the fibres and transfer

the load effectively as well as holding the

required geometry.

Of the two, PMCs are more widely used

in unmanned systems, given their excellent

strength-to-weight properties and perhaps

easier manufacturing than MMCs.

often an epoxy resin. Pre-impregnated

woven fabrics or unidirectional tapes

(termed pre-preg) already contain

the matrix resin before lay-up into a

component, and the resins contain latent

hardeners that are activated by elevated

temperatures to fully cure the material.

The curing process cross-links molecules,

and this can be an exothermic reaction,

so care must be taken in controlling the

process temperatures, particularly in thick

components. To stop the resin curing at

room temperature, refrigerated storage is

required, and pre-preg composites have

a finite shelf life.

An alternative to epoxy resins is to

use cyanate ester-based resins, which

provide excellent high-frequency radio

wave transparency as well as very

low outgassing for space applications.

Outgassing is the release of trapped

molecules or gases from a material

placed in a vacuum – the gas can then

condense onto a satellite’s instruments

or optics for example. These resins can

also have a very high glass-transition

temperature (above 350 C) as well

as high toughness, making them

ideal for long-term service in extreme

environments. PEEK (polyether ether

ketone) is a particularly popular matrix

choice for hard-wearing functional parts

exposed to high temperatures, although it

is comparatively expensive.

Polymer compositesThe most popularly known PMC is of

course carbon fibre, or more properly

carbon fibre reinforced polymer (CFRP).

However, there are many alternative

reinforcing fibres available, and each

has its own advantages depending on

the application. The most commonly

available reinforcements besides carbon

fibres are aramid-based, glass, quartz or

thermoplastic fibres.

The carbon fibres themselves can be

manufactured from petroleum-derived

pitch as a base material, or more often

from a polyacrylonitrile (PAN) polymer.

PAN fibres are heated (oxidised and

carbonised) to burn off other elements

and leave the desired carbon, after which

further heat treatments can be applied to

ManufactureReinforcement fibres are handled as a

bundle, called a ‘tow’, of unidirectional

pre-aligned fibres, typically counted in

the tens of thousands (12K being 12,000

fibres per tow, for example).

A filament winding process forms

nominally cylindrical components

by winding a continuous tow of

reinforcement around a pre-form. The

tows used range from 1K to 50K fibres

and can be wound onto a mandrel in a

pattern to provide the desired properties,

typically useful for producing shafts or

pressure vessels.

Usually tows are woven to give a fabric

for lay-up in a mould. Spread-tow cloths

take each tow strip and weave them in

alternate directions to provide a cloth with

strength in more than one direction. The

particular benefit of spread-tow fabrics is

that the intersection between each weave

is very flat, so the fibres remain almost

straight, whereas more conventional

woven fabrics ‘crimp’ the fibres to a

greater degree where each weave

crosses over another.

Despite this crimping, the most

common form for composites is as a

woven fabric, with unidirectional tows

of fibres interlaced at 90o to each other,

giving bi-directional properties. Here,

each element of the weave is typically

much smaller than in spread-

influence the strength and stiffness of the

material as required.

Aramid fibres are based on an

aromatic polyamide, with a wide range

of materials more often known by trade

names such as Nomex (a meta-aramid)

or Kevlar (a para-aramid). Meta-aramid

fibres typically have high temperature

resistance, while para-aramid fibres

have excellent mechanical properties

for a given weight. Glass fibres may not

provide the same strength-to-weight

performance as carbon fibres, but they

are comparatively ductile and cheaper.

Quartz fibres are most often used for

housings such as radomes, given their

high-frequency radio wave transparency.

The reinforcement fibres are then

combined with a polymer matrix, most

6160

Matrix revolutions

Composites are a natural fit for unmanned systems, writes David Cooper, who explains how the materials are made and used

Composites | Focus


Spread-tow carbon fibre (Courtesy of TeXtreme)

UAV using thin-ply composites for airframe components

(Courtesy of NTPT)

1716

The ethos of the Penguin

unmanned aerial vehicle is

extreme endurance for civilian

applications such as pipeline

monitoring, mapping and

search and rescue missions. In 2013,

Professor David Schmale of Virginia Tech

was one of Popular Science magazine’s

‘Brilliant Ten’ for his work in tracking

dangerous microorganisms that surf

atmospheric waves; he uses a Penguin B

platform in that work.

A Penguin B has been used by

Centum to verify its new product

LifeSeeker, an innovative aerial on-

board system that can detect mobile

telephones belonging to missing people

and report their position to search units.

The Penguin B holds the world

endurance record for a UAV, set in 2012,

at 54.4 hours of non-stop flight. It was

the company’s first model following the

establishment of UAV Factory in 2009

by Latvian Konstantins Popiks. The

‘A’ version was a prototype that was

developed while Popiks was completing

a Masters degree in engineering at

Liverpool University in England.

Popiks admits that he found

development of the Penguin harder than

he imagined, as his only prior experience

was of building and flying radio-

controlled model aircraft. As a youth he

had been part of the Latvian national

team in competitions for radio-controlled

aircraft and rocket-launched gliders,

which he built himself. Design was trial

and error, he admits, while construction

used composite airframe technology,

albeit on a ‘build it at home’ basis.

Popiks notes that once he went to

Liverpool University he was able to take a

complete UAV using mostly in-house

components. Indeed, these days it can

supply the engine and the control and

launch systems, and all sub-assemblies

are available as individual components

that can be used with other UAVs.

Whereas the B is a platform that is

sold without a data link, autopilot or

payload and is tailored for each specific

application, the latest iteration – the

Penguin C – is a turnkey package.

With this model the customer only

has to confirm the required payload.

Whereas that lack of flexibility might be

a drawback in certain applications (and

more scientific approach to design, and

he pays tribute to the quality of the staff

on his course. Advanced software tools

rather than wind tunnel testing gave the

Penguin its aerodynamic form, which has

stood the test of time.

While still at the university he found

backing to set up an airframe production

company in Latvia. “I did the design

in Liverpool, while my colleagues in

Latvia did the fabrication,” he explains.

“I worked around the clock to help them

whenever I came back on vacation.” In

the end, “two-and-a-half” examples of

the Penguin A were built and flown as

prototypes, the ‘half’ being explained

by a number of crashes during this

experimental phase.

Having been established in its

current guise in 2009, UAV Factory

developed the Penguin B on the basis

the B remains on sale) it does allow

more complex packaging within the

same basic architecture. That in turn

allows additional features to be added. It

has, for example, provided the scope to

permit the development of a parachute

landing system.

Externally the Penguin C is identical to

the Penguin B, and uses the same wing,

booms and tailplane. While its fuselage

has the same outer form, internally it is far

more integrated. The same fuel-injected

engine and propeller are used but the

differences start with the engine mounts

and extend from there. Even the wiring

harness is different. At the time of writing,

the Penguin C was in testing prior to the

first customer deliveries in late 2014.

Penguin parameters In terms of size, clearly the lack of a

human operator on board allows a

UAV to be smaller than any manned

aircraft. Overall dimensions are then a

consideration of the size and weight of

the necessary propulsion system and a

compromise between payload-carrying

capacity and the adverse effect of

increasing platform area in terms of

UAV Factory Penguin C | Dossier

We had good aero and good composite work so we had confidence in the airframe and put it out at reasonable cost

A new-generation Penguin flies

Ian Bamsey visits UAV Factory in Latvia to discover the secrets of the remarkable Penguin C

A Penguin C on the end of a catapult – normally the payload is retracted for take-off

An exploded view of Penguin C identifying the main elements

of the experience of the A model and

manufacturing refinements such as

improved moulds. It supplied its first

customer in 2010, a competitor in the

Australian Outback Challenge. In this,

contestants have to locate a mannequin

in the desert in a mock-up search and

rescue mission using a UAV and, having

done so, supply it with a bottle of water.

UAV Factory started out selling just

a composite Penguin airframe, with

customers looking elsewhere for the

other components to produce a complete

aircraft. “We had good aero and good

composite work so we had confidence

in our airframe”, explains Popiks. “We put

it out at a reasonable cost – there was

nothing else like it on the market.”

Popiks says he recognised from the

beginning that a step-by-step approach

to developing the company would be

necessary. First came the airframe, then

an increasing number of subsystems

until UAV Factory could supply a


6968

All unmanned vehicles,

be they for use in

the air, on land or in

the sea, must carry a

transponder – effectively

a radio transmitter that provides details

of the vehicle’s identity, along with

other information such as its position,

speed, altitude or depth. The word itself

is a portmanteau of ‘transmitter’ and

‘responder’, which neatly describes the

device’s functions, and it can encompass

everything from commercial off-the-shelf

(COTS) equipment ready to be integrated

into a specific vehicle, to a highly

complex and bespoke design.

At their simplest, transponders provide

information. In essence, they receive

a radio-transmitted ‘question’ from an

unmanned vehicle control station or, in

the air domain, an air traffic control (ATC)

secondary surveillance radar (SSR),

which operates in the UHF section of the

radio spectrum. When the transponder

is interrogated in this way, it replies by

disclosing its identity and any further

information requested, such as its

position, speed and altitude.

SWaPDespite the differing tasks and operating

environments of unmanned air, land and

sea vehicles, their transponders share

common characteristics. For example,

they must have a reduced Size, Weight

and Power (SWaP) burden to ensure they

do not take up excessive space, which is

always at a premium no matter how large

the platform. Weight is also an important

consideration, since heavier transponders

can reduce a vehicle’s mobility.

Power consumption is the third

consideration. All unmanned vehicles

routinely carry optronics and radar

sensors, not to mention control systems

and in some cases weapons, all of which

place demands on power consumption,

so lower consumption frees up power for

other capabilities.

In addition to SWaP considerations,

unmanned vehicle transponders have to

guarantee immunity to electromagnetic

interference (EMI). This is a safeguard

to ensure that communications links

between the vehicle and the interrogator

are not lost in the event of a release

of EMI, whether it be from naturally

occurring meteorological phenomena

or as a result of the use of electronic

warfare (EW) techniques.

There is also the need to ensure

that the radio emissions from the

transponder, and the interrogations it

receives, do not interfere with other

onboard electronic subsystems. To this

end, the US Department of Defense

has several military standards (MIL-

STD) for various aspects of unmanned

vehicle transponder technology. These

include MIL-STD-461, which concerns

transponder immunity to EMI, and MIL-

STD-464 and MIL-STD-704 that cover

transponder compatibility with other

onboard power systems.

Transponders typically use the radio

spectrum, and in the case of UAVs this

can include the VHF and UHF segments,

in a range that stretches from 30 MHz

up to 3 GHz. Both VHF and UHF

transponders have a line-of-sight range,

but given that aircraft can fly at high

altitudes, UAV transponders can have a

range of several hundred nautical miles.

Where the link between the aircraft’s

transponder and the interrogator is not

blocked by the Earth’s horizon, ranges of

about 200 nautical miles (370 km) using

a line-of-sight link are possible. That

said, an over-the-horizon range of about

330 nm (just over 610 km) is possible

using radio relay techniques. Here,

another aircraft is positioned between the

operator on the ground and the aircraft’s

transponder to ‘bounce’ the signals

Transponders | Focus

Tom Withington explains the factors that need to borne in mind when designing these safety-critical devices


Personal details

There is a pressing need to ensure that unmanned aerial vehicles can fly safely alongside their manned counterparts in unsegregated airspace (Courtesy of USAF)

All transponders must have a reduced SWaP burden to ensure they do not take up excessive space, which is at a premium

An interrogator initiates requests for data from aircraft on their identity, position and so on. This example is used by the US Navy (Courtesy of BAE Systems)

Wiring harnesses are the nerves of unmanned craft (Courtesy of St Cross Electronics)

3332

One of the core challenges

with an unmanned

system is the connectivity

needed inside the

vehicle which, given

the number and variety of sensors

and cameras being used in them,

brings with it an increased need for

communications and therefore power.

Also, instead of having a centralised

control cockpit laid out around a driver

or pilot, unmanned systems have a

much more distributed design, and this

is changing the way the cable harness

that supplies power and data around the

vehicle is designed and implemented.

This is a key element in the challenge

to reduce SWaP – Size, Weight and

Power – in unmanned systems. Less

weight means a longer range for UAVs

and driverless cars, while a smaller size

for the electronics means more space

for passengers or for larger batteries,

and the harness can take up a surprising

amount of weight.

There are many ways of delivering data

around an unmanned system. Traditional

harness designs use copper wires, but

optical fibres and even wireless links can

be used. Each of these technologies has

its challenges, but the fundamental issue

for all of them is the need to provide

power as well. Every sensor and actuator

in the vehicle needs power, and has to

deliver data back to a control unit, so the

traditional approach has been to provide

that power alongside the signals by using

separate copper cables.

In every unmanned systems market

the proliferation of sensors, telemetry and

comms – and their distribution around

the vehicle – severely restricts system

weight and size, so the lighter, smaller and

faster you can make the connectivity then

the better the platform is able to perform.

However, with new high-speed connection

protocols such as HDMI being used for

high-resolution cameras, the range of

connectivity requirements is continuously

growing. This gives the harness designer

and maker more challenges, and

highlights the separation between the

power and comms functions.

To build a harness, cables of different

thicknesses can be woven together

into a ribbon, with the thicker cables

delivering power and the thinner cables

carrying signals. The thousands of

cables required in a vehicle constitute

considerable weight and cost, however,

and while some harness makers are

starting to use aluminium rather than

copper to reduce the weight, there is also

a move to adopting different approaches

for connecting sensor units (see below).

Some unmanned systems are

able to challenge the existing design

methodologies. For example, having

solar panels on the wings and body

of a UAV allows power to be provided

closer to the sensors and actuators. This

removes the need for distributed power

cabling around the craft, potentially

reducing the complexity and weight of

the harness. However, the trade-off is

that more power management devices

have to be distributed around the craft.

This highlights the need for the harness

to be an integral part of the design of the

system, and for different architectures

to be assessed to provide the optimum

design with minimum weight.

Cabling There are various ways to build a

conventional harness, ranging from

bundling a set of wires together to

weaving them together. Cables have

been woven into ribbons for more than

45 years, but like everything else in the

modern world the harness has evolved

over that time.

At the moment, developers tend to

build a system and hang a harness

on it afterwards; going forward though,

harness makers will need to provide the

interconnectivity wherever it is needed

throughout the unmanned system. This

means that the design and project

managers can rethink wiring systems

away from conventional approaches and

integrate new methods (see below) into

their products that allow them to build

lighter systems with higher performance.

Very often the conventional harnesses

limit the design of an unmanned craft.

There are existing specifications and

conventions for the interconnections that

have been used for many years, and it

takes a brave engineer to adopt a new way

of implementing these connections instead

of something they’ve used for 20 years.

Now though, using wires as small

as 44 AWG allows a ribbon cable

only 9.5 mm wide to be built with 50

twisted pairs which provides substantial

signal connectivity. Many spacecraft

have these ribbons on either the flight

harnesses or in the instrumentation

packages and experiments.

A newer approach is to put these

ribbons inside a jacket or shell. One

application of this is to provide power for

de-icing the rotor blades of a helicopter,

and essentially these aren’t a harness

any more, but shaped components

accurate to +/- 1.00 mm with clamps and

pads built in and made from a 3D model.

This application is one of the harshest

environments an interconnection system

can work in.

The choice of shell or jacket materials

depends on the application, and typical

materials include polyurethane and

epoxy. It is possible to put 50 conductors

in a ribbon within a structure that’s 1 mm

thick and 19 mm wide; these are still built

as an add-on harness, but with UAVs in

particular the aim would be to lay the

ribbons into the airframe structure. Using

44 AWG wire to carry signals in the

Cable harnesses | Focus

Harness designs have traditionally used copper wires but optical fibres and even wireless links can be used. Each type though has its challenges


Well connectedHow do you serve an unmanned system’s need for power and signalling while keeping weight, space and cost to a minimum? Nick Flaherty reports

Weaving cables into a ribbon for a harness (Courtesy of Tekdata)

6968

Additive Manufacturing (AM)

is one of a number of

widely used terms which

refer to technologies that

manufacture components

on a layer-by-layer basis, typically direct

from digital models. While terms such

as 3D printing are more often used

in the wider media, it is important to

draw the distinction between that and

the manufacturing technologies used

industrially. Therefore this article will

focus on those technologies that show

a readiness for applications that have

rigorous engineering performance

requirements, such as those in the

aerospace industry.

AM technologies can be readily divided

into two groups: plastic and metallic.

Although some solutions are available

that allow ceramic materials to be used,

these are not generally mainstream.

Plastic AM There are three primary AM technologies

for making plastic components –

fused deposition modelling (FDM),

stereolithography (SLA) and selective

laser sintering (SLS). FDM uses a heated

extruder head to deposit plastic filaments

into a given shape, in a process often

likened to icing a cake. FDM machines

range from very low cost (sub-£1000)

‘home printers’ to high-end industrial

systems (more than £70,000) with

generally a corresponding difference

in quality, mechanical properties of the

deposited material and productivity.

The second technique, SLA,

consolidates material from a liquid

photopolymer resin contained in a build

vat; a UV wavelength laser then cures the

resin before submerging the cured layer

into the vat by one-layer thickness and

levelling the next layer of liquid resin over

the top, ready for the next cycle. SLS is

very similar in concept to SLA but instead

it uses a thermoplastic powder feedstock

and an infrared laser to sinter the powder

particles together.

Each technology has its own advantages

and disadvantages with respect to the

others, and choosing which is most suitable

depends largely on the manufacturing

requirement. For a one-off part, FDM is likely

to be the most economic, while for large

numbers of components, SLS can be very

cost-effective as it is the only technology

where multiple parts can be ‘nested’ or

stacked together in all three dimensions,

rather than being restricted to a footprint on

the build platform (as with FDM and SLA).

Although the design freedoms are

certainly greater compared to traditional

moulding processes, there is by no

means total design freedom – certain

manufacturing rules must still be

observed. For example, both FDM

and SLA require the use of supporting

structures to build any down-facing

surfaces below a critical angle relative

to the build substrate. These structures

must then be removed either by hand

or, for FDM processes where a soluble

support material has been used, by

dissolving them from around or inside

the final component. While SLS does

not require any supports (and so

perhaps provides the greatest design

freedom), thought must still be given to

the finishing of the rough semi-sintered

surface, removal of unsintered

Additive Manufacturing | Focus

Making components using an additive process is ideal for the unmanned systems industry. David Cooper explains what those processes are and how they work


It all adds up

Design freedoms allow new design approaches to improve part performance

(Courtesy of Concept Laser)

Bespoke instrument housing for satellite application (Courtesy of CRP)

Ian Bamsey Editorial DirectorIan Bamsey is a world renowned technology writer and editor. Over the past 25 years he has created publications covering the technology of

racecars and race engines and more recently he was one of the founders of Unmanned Systems Technology magazine.

Bamsey is now concentrating attention on the equally complex and innovative world of Unmanned Systems Technology. The same challenges of engineering efficiency are present here together with a lot more freedom for experimentation with alternative solutions.

Nick FlahertyTechnology EditorNick Flaherty is one of the world’s leading electronics technology journalists. He has been covering the latest developments in semiconductor,

embedded software and electronics technology for the last 25 years as a writer, editor, analyst and consultant.

His expertise is now applied to the unmanned systems market, where the technology is moving fast. He brings detailed technical knowledge, analysis and experience of hardware and software system development to deliver a unique insight into the challenges of this exciting, cutting edge market.

Content overview




















01 UST Cover 2.indd 3 01/10/2014 20:53

UST 05December/January 2016

UST 06February/March 2016

UST 07April/May 2016

UST 08June/July 2016

Ed deadline: 20/11/15

Ad deadline: 02/12/15

Publication date: 04/01/16

Bonus distribution: The Bahrain AirshowThe Unmanned Systems Expo (TUS)SkyTech




Bonus distribution: AUVSI EuropeSmall Unmanned Systems Business ExpoUMEX




Bonus distribution: XPONENTIAL – AUVSI USANext Gen DronesICUAS




Bonus distribution: Farnborough International AirshowWorld Congress on Unmanned Systems Engineering

FOCUS 1: Sense & AvoidSense and avoid technologies are an integral element of autonomous control systems. This focus article will look at the different architectures and algorithms being developed for implementations across the full range of unmanned systems.

FOCUS 2: Fuel cellsFuel cells are fast emerging as a viable energy source for unmanned systems. Our focus will look at the latest developments in the different fuel cell technologies, from the conversion stacks to the fuel storage and supply. It will also look at the management of the output power for the wide range of unmanned platforms.

INSIGHT 1: Tech Trends 2015 / 2016

FOCUS 1: Navigation systemsOur Spring focus is on the latest navigation technologies, from GPS and GNSS to the design and implementation of inertial measurement units (IMU). This article will look at the challenges of size, weight and power combined with accuracy and reliability and how these systems can be integrated with unmanned control systems.

FOCUS 2: Antenna systemsCommunication is vital for all autonomous craft, and the antenna is a vital component of this capability. This article will look at the challenges of antenna design for unmanned systems, from long range and multi-frequency designs to mechanically and electronically steerable implementations.

INSIGHT 1: Unmanned Ground Vehicles (UGVs)

FOCUS 1: UAV launch & recoveryLaunching and recovering unmanned aircraft can present a considerable challenge. There is an engineering trade off in the complexity of control systems and the design of the launch and recovery systems to provide the optimum solution for different aerial platforms. Our focus article will look at the latest solutions on offer.

FOCUS 2: Electric motorsElectric motors are starting to become a key element of many unmanned systems. This article looks materials and design of electric motors for higher efficiency from different power sources, as well how the control of electric motors is changing the design of unmanned systems.

INSIGHT 1: Unmanned Underwater Vehicles (UUVs)

FOCUS 1: Ground control systemsThe control and monitoring of unmanned systems can require a link to a ground station. We’ll look at the latest developments that provide the performance and flexibility required by the operators. The feature will include coverage of the hardware and software, as well as the impact of cloud technology on system development.

FOCUS 2: Solar powerUsing solar power is an increasingly popular option for unmanned craft. This focus article will look at the latest solar cell technologies for high energy density, low weight applications, as well as the power management technology that supports the implementation of solar power.

INSIGHT 1: Unmanned Aerial Vehicles (UAVs)













UST 2016 Publishing schedule overviewNo. Issue Ed deadline Ad deadline On sale Key features

05 Dec/Jan ’16 20th Nov 2nd Dec 4th Jan Insight: Tech Trends 15/16

Focus 1: Sense & Avoid

Focus 2: Fuel cells

06 Feb/Mar ’16 22nd Jan 5th Feb 22nd Feb Insight: UGVs

Focus 1: Navigation systems

Focus 2: Antenna systems

07 Apr/May ’16 18th March 1st April 18th April Insight: UUVs

Focus 1: UAV launch & recovery

Focus 2: Electric motors

08 Jun/Jul ’16 20th May 3rd June 20th June Insight: UAVs

Focus 1: Ground control systems

Focus 2: Solar power

09 Aug/Sept ’16 22nd July 5th Aug 22nd Aug Insight: USVs

Focus 1: Data storage

Focus 2: Simulation/Testing

10 Oct/Nov ’16 23rd Sept 7th Oct 24th Oct Insight: Space vehicles

Focus 1: Performance monitoring

Focus 2: Embedded computing

UST 09August/September 2016

UST 10October/November 2016




Bonus distribution: Commercial UAV Show AsiaCommercial UAV ExpoInterDroneUnmanned Global Systems (UGS)




Bonus distribution: Commercial UAV ShowUnmanned Systems CanadaUVID – Unmanned Vehicles Israel Defense

FOCUS 1: Data storageThere is a fundamental trade off between the need for data storage and the communications bandwidth available for unmanned systems. We’ll look at the latest technologies, from flash memory to magnetic media and the interface standards to access them. Bandwidth, reliability, scalability and management are all key factors to consider.

FOCUS 2: Simulation/TestingThe development of unmanned platforms can be accelerated and improved with the latest simulation and testing technologies. We’ll explore both hardware & software-in-the-loop (HIL & SIL) technologies that are optimised to reduce the cost of development and improve quality.

INSIGHT 1: Unmanned Surface Vehicles (USVs)

FOCUS 1: Performance monitoringOne of the key challenges and advantages of autonomous systems is to have them return to base for maintenance before a failure happens. This needs increasingly complex performance monitoring sensors and algorithms, and we’ll consider the different approaches to delivering the capability, from hardware to software and how this impacts on the overall system design.

FOCUS 2: Embedded computingMainstream computing platforms are increasingly able to provide the control of unmanned systems. We’ll explore elements ranging from the processor and memory technologies to how boards and systems are used for such platforms.

INSIGHT 1: Unmanned Space Vehicles

Forward features





















01 UST Cover 2.indd 3 01/10/2014 20:53


Where in the world

Readership

Unmanned Systems Technology magazine is read by engineers around the world actively working on developing technological solutions for unmanned vehicles and the systems that support them. Written by engineers, for engineers.

48%

21%

15%16%

USA UK

Rest of Europe Rest of World

Core circulation – individually mailed copies6,000Readership (average 3 readers per copy)18,000• Chief / Head / Lead / Principal Engineer (UAV, UGV, USV, UUV) • Aerospace Engineer • Airworthiness Engineer • Chief Scientist • Developers • Development Engineers • Director of Design • Electronic Design Engineers • Embedded Software Engineers• Head of Innovation • Lead Robotics Engineer • Materials Managers• Mechanical Engineers • Program Managers • Project Engineers• R&D Engineer • Robotics • Researcher • Senior UAV Technician • System Integration Engineers • Technicians • Technology Researcher • UAS Logistics Analyst • UAV / UAS Operator • UAV / UAS Pilot • UAV Specialist












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Full pageTrim: W210mm x H297mm Bleed: W216mm x H303mm Type: W190mm x H277mm

Half page (V) Type area: W92.5mm x H277mm

Half page (H) Type area: W190mm x H136mm

Quarter pageType area: W92.5mm x H136mm

Specifications:

Artwork can be supplied in PDF, EPS, TIFF or JPEG formats. Artwork to be set at 300dpi.

Alternatively we do offer a design service by arrangement, so if you would like us to help make an advertisement for you, or amend an existing ad, then please get in touch to discuss.

Advertising rates and specs

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01 UST Cover 2.indd 3 01/10/2014 20:53

Fact not fiction. Science not speculation.

Editorial enquiries Ian Bamsey – Editorial Director – [email protected]

Nick Flaherty – Technology Editor – [email protected]

Advertising enquiries Simon Moss – Publishing Director – [email protected]

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Subscription & General enquiries Chris Perry – General Manager – [email protected]

All digital enquiries Caroline Rees – Online Advertising Director – [email protected]

High Power Media Ltd Whitfield House, Cheddar Road, Wedmore, Somerset, BS28 4EJ, UKTel: +44 (0)1934 713957 Fax: +44 (0)20 8497 2102 www.highpowermedia.com • www.ust-media.com

UST has quickly become the magazine to study in our team as there is a real focus on the engineering perspective.

Phillipp Volz, CEO, Volz Servos

The magazines are brilliant. We use our UAVs for 3D topographical surveying and have built our own in the past. UST helps us keep up to speed with the ever changing industry.Stephen McManmon, Senior Engineer, Shannon Valley Group

UST covers the unmanned industry from the perspective no other magazine does – from an engineering point of view. Articles dig deep to explore the technical aspects of unmanned vehicles, from the technology used to the manufacturing methods involved. This approach is of great interest for anyone who is involved in designing unmanned systems.

Rory Bauer, Sales Director, UAV Factory

I have enjoyed the issues to date for their technical insight and depth of coverage. It is very difficult to find articles that are both readable and technically satisfying – in my opinion you strike an excellent balance!

Grant Shipley, Engineer, GeoSpatial Innovations, Inc.

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