Monocopt

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A Typical Monocopter Model

Monocopters are single winged, all-rotating powered flight vehicles modeled after falling maple seeds.

As a potential new Unmanned Aerial Vehicle (UAV) platform, monocopters are inexpensive ($50-100), mechanically simple (two moving parts), and quick to construct (under 3 hours in a laboratory setting).

Monocopter?????

Hobbyists have been tinkering with monocopters in one form or another since the 1960s.

Monocopters were purely curiosities: lack of effective control has excluded them from practical applications.

As a result the dynamics of powered monocopter flight were not properly demonstrated till a few years ago.

The closest published reference to control of a monocopter is a 2007 Master’s thesis by Andreas Kellas at MIT. In his work, Kellas discusses the implementation of a rudder-control scheme for an autorotating vehicle similar to a maple seed. While Kellas does not clearly demonstrate control in flight tests, his work shares the challenge of detecting the orientation of an all-rotating vehicle.

Brief History

Recently the monocopter ‘s tremendous capability of being an UAV was succesfully showcased in IARC by Embry Riddle Aeronautics Institute

Model of Embry Riddle

Monocopter prototype

We choose the lightest available R/C components for the receiver, motor, battery, speed control, and servo.

Wing is made of polystyrene or balsa wood so that it is sturdy as well as strong.

Fuselage is to be made with carbon fibre.Lithium polymer batteryBrushless motorPropeller with three or more blades is necessary to

eliminate excessive vibration due to varying propeller inertia about the monocopter’s vertical axis of rotation.

A launch lug located on the motor arm at the vehicle’s center of mass accepts a vertical rod from the launch stand, and enables the monocopter to freely seek its steady state pitch and coning angles prior to takeoff.

Design parameters

The rotation of the monocopter results in the change in angular momentum of the propeller. With respect to time.

This creates a torque on the monocopter frame about the pitch axis.

This inturn is balanced by the spinning inertia of the pitch balance strut.

The monocopter rotation direction determines whether this torque causes a pitchup or pitch-down deflection.

While in flight steady state coning angle balances the torque from lift on the wing, and a steady state pitch angle balances the pitch torque due to yawing the spinning propeller.

Working

Side View: Coning angle

Side View: Pitch angle

A monocopter launch pad should be sturdy and fixed firmly to the ground.  Never try to launch a monocopter from a long rod on a standard launch pad. A suitable launch pad can be constructed from the following materials:

1. 4 - 2x4s, three, 18 inches long and 1 - 2x4,, 36 inches long. The lengths need not be exact.

2. 1 - 3 inch long, ¼-20 carriage bolt aand 3 nuts3. 6 -3 inch long wood screws.Drill a 1/4” hole in the middle of one of the short 2x4s. Insert the

carriage bolt into the hole and secure it tightly with one of the nuts. Attach the long 2x4, perpendicular to bottom of the short one with two wood screws. Attach the two remaining short 2x4s to the opposite ends of bottom of the first short 2x4 with two wood screws each.  Thread the two remaining nuts on the bolt and use them to adjust the height of the rocket above the pad.

Launch Pad

In uncontrolled flight (throttle control only), monocopters are either directionally stable or unstable.

Stable models hover fixed in space, translating no more than two disk diameters per minute.

Unstable models spiral clockwise in circles of increasing radius, with ever increasing disk inclination.

After the first hindrance of making a monocopter hover is overcome,next aim is to make it navigable.

Points to be taken care of

Use of ailerons on the wings to navigate the monocopter was thought about.

The problem that can be encountered is in addition to modifying the lift of the airfoil, the aileron also influences the aerodynamic moment about the quarter chord. The aerodynamic torque due to aileron deflection is small compared to the torque generated dueto the lift distribution, but causes pitch oscillations.

First we will be trying to make the monocopter hover at one place.

This will be done with the help of various wing designs and known aerodynamic concepts.

In market,monocopter kits are available which are solely made of balsa wood.So this will be good means of conducting hit and trials if we model our initial models with balsa.

Plan

Balsa monocopter

After getting a apt solutions,we will make our final model using carbon fiber,polysterene foam sheets etc.

Then comes the problem of navigating .This requires greater avionics.With use of inclinometer we will judge the various

flight parameters and code a microcontroller so that it control the ailerons effectively.

By varying that angle at the right times during rotation, you gain contol that is similar to the control provided by a swashplate in helicopters.

http://www.youtube.com/watch?v=sbuGCgc-JCM

http://www.youtube.com/watch?v=u23Hqq8QbeE

http://www.youtube.com/watch?v=a2inEjl6ju8&feature=player_embedded

Reference Video Links

Brushless Motor-200Carbon rod-350-400Propeller-40-70Lithium polymer battery-750Balsa wood-Epoxy-500Firecracker rocketsRest of the components will be available with

aero club like receiver and transeiver.

Budget

Further modifications can be incorporated into this like

i. A wireless camera for survelliance.ii. Fly it in auto pilot mode using inclinometer

and gps.iii. Decreasing its wing span to enable it sneak

into small spaces for spying.

Future Scope of Project

Thank You

Mohammed RhazyMob no-9281375905