- Assemble the electromechanical system of a quadrotor (joystick control, autonomous control).
- Program interfaces between embedded computer (Raspberry Pi running Linux) and external sensors and actuators (IMU, motor controllers).
- Program and tune a time-critical control loop for stable flight.
- Create software stack that interacts with low-level code to achieve high-level behavior including:
- Control the quadrotor with logitech joystick (demo).
- Autonomous flight with HTC vive lighthouse (demos).
- Raspberry Pi
- IMU
- SD Card
- Wifi Dongle
- Motor Controllers
- Logitech Joystick F310
- HTC vive lighthouse
- Set up IMU, SD card, wifi dongle, Raspberry Pi.
- Calibrate gyro from X, Y, and Z direction, roll and pitch angles from corresponding X, Y acceleration.
- Add complimentary filters to reduce the noises from acceleration in short term and drifts from gyro in long term.
- Add safety check and control.
- Build quadrotor from commodity parts.
- Check safty control.
- Set up proportional control (P control) w.r.t pitch.
- Set up proportional + differential control (PD control) w.r.t pitch.
- Set up proportional + integral + differential control (PID control) w.r.t pitch.
Here is the electric system schematic diagram for quadrotor:
Here is the assembled quadrotor:
- Tune the PID w.r.t pitch.
- Build connection between joystick and quadrotor via virtual machine.
- Test pause, unpause, calibrate, kill all buttons on the joystick.
Here is what can each button on joystick do:
- Tune the PID w.r.t pitch, which eventually reduce the overshoot and transient time.
- Add desire pitch control on joystick (±25 degree). check joystick here
- Add Thrust control on joystick (1250 ± 100 pwm).
- Set up proportional control (P control) w.r.t roll.
- Set up proportional + differential control (PD control) w.r.t roll.
- Set up proportional + integral + differential control (PID control) w.r.t roll.
- Tune the PID w.r.t roll, which eventually reduce the overshoot and transient time.
- Add desire roll control on joystick (±25 degree). check joystick here
- Add desire yaw control on joystick (±45 degree).
- Ground flight test (fly from one point to another point at low level).
- Change the desire pitch & roll control on joytick to ±10 degree.
- 2-feet flight test (fly from one point to another point at 2-feet).
Start from week 8, we switch from joytick control flight to autonomous flight by using HTC vive lighthouse and its corresponding sensors.
- Assemble vive sensors to the chassis of quadrotor.
- Test sensor by reading the data.
- Add safety control during automonous flight.
- Add autonomous control for yaw, which have pitch axis (front of the robot) to always face in -y direction (proportional control).
Here is vive lighthouse we use:
Here is assembled quadrotor with vive sensors:
- Add autonomous control for X, Y direction (proportional + differential control).
- Add filters for autonomous control for X, Y, and yaw to reduce the noises from vive light house.
- Mix the autonomous control and joystick control for X, Y, and yaw.
- Test autonomous control so far by Using joystick thrust to keep quadrotor about 2 feet off ground.
- Add autonomous thrust control (Z direction, height off ground) (calibrate Z acceleration, average Z acceleration, fuse Z velocity).
First:
Second:
