EE192: Mechatronics Design Lab

Checkpoint 8

By this checkpoint, you should have a rough version of the entire project done. Your car should be able to follow a track, which will be set up in a figure-8 shape and following NATCAR specifications (single bright line in the center of the track on beige-ish carpet). Your control loop should be stable enough to not lose the track or be confused by the self-crossing track.

You will also be required to show plots from your car's telemetry. I recommend taking a look at the telem_struct in LineCamera.c for getting started with saving batch telemetry. You can build off of the python plotting from homework 1 or the Matlab plotting provided with homework 2 for generating the plots.

The figure-8 track specifications are follows:

  • 1 meter radius on each 300 degree circular lobe (this radius is 4 inches larger than NATCAR minimum)

  • 60 degree linear crossing in the center, line segment beginning tangential to the circle

  • White tape on dark carpet

Checkoff Procedure

  • Your car will be dropped from a 1-foot height, simulating a crash. Nothing should break loose, and the car should continue to function.

  • After being dropped, the car should acquire the figure-8 track and run three consecutive full laps. You may use a wireless command to tell the car to start or stop running, but no other commands may be sent to the car.

  • There is no speed requirement.

  • It is required to have an e-stop (something big like a flag/stick, connected to a switch that will stop the car from moving)

  • After following a closed-loop tape course figure-8, show telemetry plots of the following vs. time in seconds (each is worth 0.1 point towards checkoff 8):

1. waterfall plot of raw line camera data or plot of detected line position (in cm)

2. velocity in m/s or cm/s

3. steering servo command from -1.0 (full left) to 1.0 (full right) or -100 to 100 if you prefer ints.

4. motor duty cycle (-1.0 full backwards/braking to 1.0 full forwards or -100 to 100). If you are using an H-bridge with both reverse and braking functionality you should plot multiple signals.