Brandon Skari is planning on entering the 2015 competition. The chassis is based on a Tamiya Grasshopper RC car. The car is driven by a Raspberry Pi model A+ driving PWM. Telemetry is provided through a GPS/compass/accelerometer module. Basic obstacle avoidance is planned using a Raspberry Pi camera module. The control program uses an extended Kalman filter to estimate the vehicle's position.
Brandon Skari entered in the 2014 competition. The chassis was a Radio Shack Dune Warrior RC car, operating at 49 MHz. The car was driven by a Raspberry Pi model B that generated a radio signal that controlled the vehicle. We used an oscillopscope to observe the radio signal from the transmitter and decode it. Telemetry and a "physical" start and stop button were provided by an Android phone running a custom app. The system was carefully designed to fit in the $350 budget to be able to compete in the PBR division.
The car used telemetry (including GPS, compass, and accelemerometer readings) directly from the phone. The phone only updated GPS at 1 Hz and the control software didn't try to do any position interpolation, so the car had to drive pretty slowly. The car would drive to a set of waypoints and go to the next one once it was within 1m. No collision avoidance was included; rather, collision detection using the accelerometer and GPS speeds was implemented, with backing up recovery.
The car didn't perform well at the competition. The compass went haywire at the competition and caused the car to behave erratically, including turning left and driving straight into the haybails at the beginning, or driving straight from the line, turning 180 degrees, and repeating this indefinitely. A lot of other competitors reported compass problems and seeing local interference from the ground. The car did make it around the course autonomously once during a practice run, but not during the actual heats.
We have been talking a lot about making an entry in SparkFun's Autonomous Vehicle Competition. This year's [SparkFun AVC] will be held on June 16th, 2012.
What does everyone want to work on? Some questions to consider:
- What kind of chassis?
- Motor? Electric? Gas?
- What sensor package do we want?
- Sonar distance?
- IR distance?
- Depending on sensors and chassis we will have to decide what electronics control package is best.
Keep in mind that we could view our entry strategy in different ways. Being awarded as "the fastest" comes with a monetary prize, which would be a great opportunity for our space, but we could also choose to make our statement a different way. In 2011, in addition to the fastest, there were awards for:
- Crowd Pleaser (Most Entertaining)
- Engineers Choice (Best Technical Design)
- Kill Switch Award (Most Dangerous)
- Water Hazard Award (Finds the Pond and/or Stream)
- Rookie Award (Best First-Time Competitor)
- Best Dressed (Most Interesting Costume/Vehicle)
If you are interested in this project we would love to get it moving ahead, please contact us through our Google Group and/or attend one of our meetings.
Members involved (add yourself if you're not here):
- Dan Davis-Boxleitner
- Liz Baumann
- Christian Macy
- Ross Hendrickson