Encoder Project Introduction
Our project involved adding an encoder component to the MAE 148 Autonomous Vehicle we previously built. The motivation for this project was to have access to data concerning the speed and distance travelled in order to improve speed control.
The original configuration of the vehicle controlled the speed of the car by controlling the voltage from the battery to the motor. This voltage was based on data from user inputs(explain in step 1). The encoder allowed the voltage to be based on data concerning the actual current speed, giving the vehicle could have cruise control capability.
Step One: Build the Autonomous Vehicle
Acrylic Board: We used calipers to measure the dimensions of the mounts on our base and then laser cut an acrylic board with holes to mount our 3D printed camera mount.
Camera Mount: We designed and printed a mount to hold the camera at the appropriate height and angle to capture the track. We also included a slot to pass the cord band through without damaging it.
RPI Holder: We 3D printed a small piece to hold the RPI on our car.
Wiring Schematic: We clearly documented our wiring (right).
Step Two: Mount the Encoder
We used an optical quadrature rotary encoder with a resolution of 600 pulses per revolution. This encoder produces two square wave outputs which can be used to determine the distance, speed, and direction that the encoder is is turned.