UAV Automated Flight & Seeded Fault Control

Detailed Design ReviewAurora Kiehl

Jeremie SnyderScott NeumanDennis Vega

Stephen Wess

Agenda• Project Goals

• Aircraft Selection

• ArduPilot Overview

• Data Acquisition

• Data Logging Capabilities

• Seeded Fault Designo Mechanical Implementationo Electrical Implementation

• Video System Cost Analysis

• Imaging System

• System Integration

• Preliminary Test Plans

• Bill of Materials

• Risks

• Future Plan of Action

Project GoalsUAV project consists of three overarching goals:

1. Demonstrate the capability of automated flight between GPS waypoints for future use with proposed Imaging Science project

2. Incorporate ability to initiate seeded faults and detect that they have occurred

3. Log flight data, fault status, & on board accelerometer data

4. Display live video feed to users on the ground and allow user to capture still images in flight and store these images for viewing after landing

RC Aircraft SelectionHobbico Nexstar Mini EP

Price: $170.00

Wingspan: 3.7ft(Meets spec: wingspan < 5ft)

Electric Powered

Balsa Wood Construction(Easier to modify than foam construction)

Independent Aileron Control(Meets spec allowing for loss of control for one aileron only)

Image Credit: modelairplanenews.com

ArduPilot Overview3DRobotics ArduPilot w/ ArduPlane Software

Price: $310.00

Allows for automated flight via GPS waypoints(Meets need for automated flight capabilities)

Includes instrumentation for measuring roll, pitch, yaw, altitude, and ground speed

(3-axis gyros/accelerometers/magnetometers, barometer, GPS unit)

Collects measurements at either 10Hz or 50Hz (GPS data @ 5Hz)(Meets data refresh rate spec)

Automatic data logging w/ 4MB of onboard memory

ArduPilot

Relay for aileron fault

Cross Section

Top View

ArduPilot Simulation

By using X-Plane Flight Simulator, a hardware-in-the-loop (HIL) simulation can be performed on ArduPilot.

X-Plane provides ArduPilot with GPS and sensor data similar to a realistic flight and ArduPilot flies the plane.

ArduPilot Simulation

ArduPilot Simulation

ArduPilot Simulation

Data Acquisition

3-axis accelerometer x3

Sensitivity Range:Selectable ±1.5 or ±6 g

Analog output

Data Logging Capabilities

12 Channels of 10-bit ADC

15ksps ADC capability, >50 Hz sampling based on available CPU time

~330kB accelerometer data for 10 minute flight@ 50 Hz

Rudder FailureServo pulls pin connecting upper and lower sections of

rudder

Loss of control of upper rudder section

Open circuit indicates fault has been successfully seeded

Fault Detection Circuit

Wing Section FailureServo released spring loaded portion of wing section

Lower section of wing protrudes into the airflow Broken electrical connection pulls down fault line

Fault Detection Circuit

Fault door

Wing Fault - Door

Aileron FailureRelay allows aileron to be deactivated, thus limiting the

aircraft to using a single aileron for roll control.

Video System AnalysisCMOS 26N/P

- Less risk in integration than Keychain #16

- Bandwidth

5.8 GHz Tx/Rx Kit- Lower risk of signal loss beyond "line of sight"

ArduPilot Mega MinimOSD R1.1

Goggles too costly for current scope (~ $250)

Separate battery pack for video system- 11.1V, 1250 mAh

Source: 3D Robotics

Imaging SystemCamera capable of capturing still images to be installed on

aircraft

Command sent through ArduPilot will trigger camera to take image

Low mass, high resolution camera desirable

Option #1HD Mini CameraCost: $30Image Resolution: 12Mp?USB ChargerMicro SD card storageShips from China

Image Credit: www.k-ding.cn

Imaging SystemOption #2Smile Button Hidden CameraCost: $60Image Resolution: 3MpUSB ChargerMicro SD card storage

Camera to be reversed engineered, allowing a voltage signal to emulate user action to capture image

Image Credit: www.internetsiao.com

Remote Camera Trigger Circuit

The Switch on the camera can be replaced with an NMOS pass transistor, which acts like an open circuit when the input is 'low' and a short circuit when the input is 'high.'

System Integration

Testing: Ardupilot

Ensure signals pass through Ardupilot in Manual Mode

Ensure all data of interest is collected and stored properly.

Manually fly UAV to certain altitude, switch to fly-by-wire A mode and verify it flies to waypoints

Datalogging Capabilities can be tested by running Ardupilot and collecting data for 10 minutes and determining if it fills up the 4MB onboard flash memory.

Testing: Ground Station

Ensure that ground station can communicate necessary information with the UAV remotely on ground

Verify that all servos can be controlled either using the laptop or controller

Modify Ardupilot Mission GUI to add fault and imaging features, verify that these features perform as required on ground

Testing: Fault Seeding/Detection

Test that all faults can be triggered on the ground and occur as expected

Run vibration test on fault detection system and make sure the accelerometer data is stored and looks as expected

Create a circuit that "open circuits" when a fault occurs, obtain timestamp when this occurs for correlation with accelerometer data by future groups

Testing: Video/Imaging System

Use the video transmitter to verify that video is sent to laptop remotely on the ground.

Verify remote triggering of ‘Take Photo’ command works and saves the photo on the UAV.

Testing: Power Subsystems

To ensure our ideal flight time of 10 minutes, All batteries should last at least this long

The current draw for all components can be thoroughly tested on the ground: the battery life will be equal to the strength of the battery (mAh) divided by the total current draw

Bill of Materials

Updated Risks

Future Plan of Action