Wireless Base Station

To help with debugging, we created a base station for our own computer that could communicate both ways with the car. We did this by using a USB to serial adapter and another USB cable to power the 5V that the on-board wireless chip needs. This was absolutely essential in debugging; we went from having a completely non-working car (with most systems including speed control down) the Sunday before the due-date, to a solid, reliable car ready for the demo on Wednesday night, mostly thanks to this system we could hook up to our laptop and take with us to collect data. Here’s a list of a few items that were helped with the wireless base station:

• We used it to collect the time between hall pulses, which eventually led us to discover the bug with speed control
• We used it for efficient PID speed calibration (<10 minutes)
• We used it to create a manual turning scheme for obstacle avoidance
• We used it to report the duty fraction for steering control to determine at various points whether turning calibration errors were due to hardware or software
• We used it to output on interrupts to make sure they were firing correctly when we wanted them to
• We used it to report on the ticks elapsed on the negative edge from the camera so that we could figure out quickly how many ticks corresponded to the center of the line
• We used it in all of our extra features