Eclipse Sun Tracking

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The PCB, "Patriarchy Crusher," leverages the HONEY architecture to control H-Bridge motor driver ICs.

PCB Design

The design incluedes:

HONEY compliance

  • DataBus connectors for regular updates from the avionics bay
  • PowerBus connectors for the 5V, 3.3V and 12V power supplies
  • Can Transceiver for Avionics Communication
  • Terminating Jumpers for the CAN bus

Motor and Servo Connectors

  • Connector spots (J8-J15) are for the male header pins. Servos can connect to these. Each Servo gets a 3.3V supply, a capacitor to smooth the movement, and a PWM signal.
  • Connector spots (J3 and J6) are for larger motors to connect to. These connectors allow each motor to get a power, direction signal, and PWM signal. These connectors also offer extra space for GND.

Control System

  • HBridge Drivers (U4A and U4B) take directions via i2C from the teensy and drive two motors each
  • Jumper pin holes (J4 and J7) allow the user to choose between a 5V and 12V supply for his/her motor. There are also corresponding capacitors to smooth out any power spikes.
  • The teensy 3.2 (U1) takes in directions from the CAN transceiver and directs the PWM driver and motor drivers
  • The PWM driver (U3) connects one channel to each motor and servo allowing for a unique pulse length for each output.


Pcb schematic.png

Pcb trace view.png

Applications

Eclipse Sun Tracking

The motor driver board controls motors for the sun tracking project. The software reads orientation data from an IMU, the BNO055, and compares the heading to the sun's expected Azimuth. Based on the difference between the Azimuth angle and the heading angle, the teensy on Patriarchy Crusher uses a PID to command the HBridge driver to turn the motor clockwise or counterclockwise. The end effect is that the GoPro is rotated to face the sun and can thus take pictures of the eclipse. You can watch the results here.