1. Autonomous Quadcopter Andrew Martin, Baobao Lu, Cindy Xin Ting Group 37 TA: Katherine O'Kane

2. Introduction ●Quadcopter industry is developing rapidly, with minimal regulation ●FAA has developed a network of laws to discourage hobbyist flying [1] ●Most quadcopter accidents can be attributed to ○Inexperienced flyers. ○Cheap quadcopter design ○Collision with objects the pilot couldn't navigate around We can reduce accidents by developing cheap, autonomous quadcopter flight [1]http://www.quadcopteracademy.com/faa-drone-regulations/

3. Objective Input free quadcopter control on a budget No user input, preplanned quadcopter route Simple, cheap collision avoidance with ultrasonic sensor

4. Design, Requirements, and Verification Block Diagram

5. Design, Requirements, and Verification Block Diagram

6. Design: LiPo, ESCs, and Motors Lipo Battery: Directs 11.1-12.6 Volts to Electronic Speed Controllers (ESCs) ESCs: Supplies power to all quadcopter components 20A power supply to motors Battery eliminator circuit (BEC) powers: Flight Controller, ARM board, Ultrasonic Sensor Motors: Brushless 220W, Spin propellers when powered by ESCs Adapted from: http://2bfly.com/assets/bldcwiring1.png

7. Design, Requirements, and Verification Block Diagram

8. Design: Flight Controller Controls ESC’s transmission of power to motor CC3D Flight controller Hardware flight controller OpenPilot Firmware Configured with CleanFlight software https://espritoutdoor.files.wordpress.com/2015/11/f707c-12139575_547606095391 832_1623748767_n.jpg?w=630

9. Design, Requirements, and Verification Block Diagram

10. Design: ARM Board (LPC1114FN28) Transmit PWM signals to flight controller’s (CC3D) receiver inputs. Communicate with ultrasonic sensor (HC-SR04). Making decisions to control the quadcopter on a set flightpath.

11. PWM Signals Both signals at 50Hz (20ms), size of pulse is 1ms for the left side and 1.642ms on the right.

12. State Diagram of ARM

13. Pseudocode

14. Design, Requirements, and Verification Block Diagram

15. Design: Ultrasonic Sensor Send ultrasonic distance data to ARM Protoboard once triggered. To prevent trigger signal conflicting with echo signal, measurement cycle must have a delay between pulses of at least 60 ms.

16. Distance (cm) Expected Duration (μs) Obtained Duration(μs) 12345Average% Error 2.00116.4239.0238.0232.0237.0 236.650.80 4.00232.8321.0328.0326.0344.0326.0329.029.24 6.00349.2376.0 383.0382.0405.0384.49.16 7.00407.4414.0408.0409.0 408.0409.60.54 7.50436.5436.0435.0436.0431.0434.0434.40.48 8.00465.6466.0473.0 472.0471.0 1.15 20.001164.01197.01203.0 1228.01203.01206.83.55 50.002910.02965.02966.02989.02965.02966.02970.22.03 55.503230.13330.03281.03330.03304.03299.03308.82.38 75.004365.04448.04424.04426.04449.04455.04440.41.70 100+>5820.0 Outputs random number possibly due to lack of power from arduino Testing Ultrasonic Sensor using Arduino

17. Sampling (using ARM board) Get ultrasonic sensor results a few times and count the number of times object is detected and set a threshold. Without sampling, LED was seen blinking near maximum range. Number of samples = 10, results were not stable regardless of the threshold value. Number of samples = 20, we were able to get more stable values at threshold = 18.

18. Project Build and Functional Tests: PID Tuning PID Proportional-Integral-Derivative controller using loop feedback. Done in CleanFlight. Set of tuning parameters that controls the operation of the PID controller. P: affects the magnitude of correction needed to bring aircraft to certain position. I: helps correct errors D: Damping to rotor speed. Obtaining Controller values From CleanFlight PID tuning affects the controller values

19. PID Tuning tests PID values Controller values Throttle, Roll, Pitch and Yaw NameProportionalIntegralDerivative Roll4.00.0623 Pitch4.00.0623 Yaw8.50.0450 Upward Throttle Hover/ Hold Down Throttle Pitch (left) Pitch (right) Roll (left) Roll (right) 1670164015801443153314461534

20. Project Build and Functional Tests: Hardware Hardware component: Power supply for ultrasonic sensor Very steady 5V required to operate ultrasonic sensor Voltage regulator burned out, produced 5V±0.5V Obvious fix, use BEC from ESC (5V±0.01V)

21. Successes and Challenges Challenges PID Tuning Drifting, undesired movements. Sensor Sensitivity Hardware Component setbacks ESCs burning out Fragile Propellers Success Motor Calibration Automated flight with control over pitch, roll, and yaw Sensor Detection of objects

22. Conclusion and Future Work Quadcopter follows autonomous paths with integration of sensor Detection of objects results in “disarm”. Incorporate more ultrasonic sensors Reliable ultrasonic sensors More advanced flight paths