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Figure 2.11: Portion of code that communicates with the Jaguars.
Figure 2.12 shows the structure of the ROS nodes centered on the Arduino. /Serial node represents the
code running on the Arduino. The values from the remote and the wheel encoders go to the /jag listner
node, which is the code that runs on the robot mentioned above. /remoteControl is the values from the
remote, and /wheelEncoders are the values from the encoders. Also pictured is /cmd vel, which goes into the
/jag listener node. /cmd vel is the distance and theta command from our mapping node. The line coming
off of the bottom of the /serial node is what transmits the encoder information to the EKF.
Figure 2.12: Portion of the RXGraph that deals with the Jaguars.
2.2
Results
After the new system was fully in place, a few results were immediately noticeable. With the cRIO
gone, and the Arduino mounted to the shield, there was a noticeable increase in space inside of Prometheus.
Programming the Arduino was easy with the included Arduino IDE, and downloading code required no
external computer, and was almost instant. The system redesign was first tested using remote control.
Operating the robot in tele-operational mode allowed for Prometheus to move around very reliably. All
of the sensors were tested under the new design, and all functioned without an issue, with no decrease in
performance.
After implementation, it was determined the best way to test the improvement expected from better
communication and rear encoders was to do a distance test. Prometheus was driven a set distance of 3.5
meters with the old architecture, then the new. The results are shown in Figure 2.13.
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