-Specifications- Processors: Cygnal C8051F0226, Visor Prism Power Source: (5) 4/3 AA @ 3700 mah Weight: ? OS: Palm OS Programming Language: C and Pocket Studio Sensors: (6) QRB1114, (1) GP2Y0D02YK Motors: (5) R/C Servos - CS-61 Output: n/a Time to Build: 3 months Cost: ~$400.00 USD Status: Completed

Juggernaut was designed for the purpose of competing in the RSSC October 2002 Line Fetch Contest. Juggernaut received 1st place in the line fetch contest, and 2nd place in the Talent contest.

The Contest:

The rules are simple; follow a black line on a white surface until you locate an aluminum can (beer, soda, whatever), pick up the can and return to the start of the line. Once you have returned to the start of the line, set the can down and back away. The fastest robot to successfully complete the above task wins…..

I was more concerned with reliability that I was with speed, I knew that I would always be able to crank up the speed if necessary, however, speed is absolutely worthless if you are unable to complete the task.

During the software development phase of this project, I encountered a problem with the line following sensors. They where a pain to adjust, every time you changed lighting conditions, or your battery level was a bit low, etc. these damn sensors had to be re-adjusted by moving their position up or down. Fortunately I was using the Cygnal F0226 processor on this robot to handle all of the motors and sensors. As it turned out, pretty much all of the I/O Pins can be analog inputs or digital I/O. Things became clear; I simply re-configured the line following sensor inputs as analog inputs and incorporated a calibrate button on the Visor device. This allows me to re-calibrate my line following sensors on the fly. This feature alone brought juggernaut's reliability up to the 90% area. With the addition of a few software tweaks and logic changes I was able to get Juggernaut to complete the line fetch task 19 out of 20 times in a row.

All of this toil paid off; during the competition, Juggernaut successfully completed the fetch operation in all three heats. Although Juggernaut was the slowest robot, he was by far the most reliable.

Construction:

Juggernaut was constructed using 6061 1/8 inch aluminum plate, and held together by 1/16-inch angle brackets, all of the parts where hand cut on either a band saw or scroll saw. It took about 3 months to cut and assemble all of the parts. Juggernaut has 2 processors, a master and a slave; the slave processor is a Cygnal C8051F0226 operating at 16mhz. This processor takes care of the servo motor PWM generation and the sensor input / translation. The master processor is a Visor Prism, operating at 33 mhz, the Visor takes care of all high level functions, GUI, logic and decision making. The Visor communicates with the Cygnal processor via serial - 3v TTL @ 57600 bps. The Cygnal processor responds to the commands and returns the results of the operation. Juggernaut has a top speed of ~1.5MPH and the batteries can last up to 12 hours, depending on what operations are being performed.