Electrostatic discharge events (aka “ESD events”) have the potential to disrupt the normal operation of competition robot. As a robot moves across the floor of a FIRST Tech Challenge field, the robot tends to accumulate positive electrostatic charge on its metallic frame due to a physical phenomenon known as the triboelectric effect. The charge that builds up on the frame can be significant (on the order of 25kV or higher). If the charged robot touches another conductive object (such as a metallic game element, the perimeter wall, or another robot) that is at a different electrostatic potential value, an electrostatic discharge can occur and current will flow from one conductive body to the other as the charges equilibrate. These ESD events can disrupt, or in rare cases, damage the Control System electronics on a competition robot.
Charge is transferred from wheel to floor due to the triboelectric effect.
Electrostatic buildup is a problem in robotics competitions (including the FIRST Robotics Competition and the FIRST Tech Challenge) and in industry (especially, as an example, for applications involving conveyor belts).
Fortunately, there are some simple, but effective steps that you can take to minimize the risk that an ESD event will disrupt or damage your competition robot. These steps are outlined in the FIRST Tech Challenge Wiring Guide and as part of the FTC SDK documentation of ftc_app GitHub repository.
If you’d like to learn more about electrostatic discharge effects, there is white paper that was written by Mr. Eric Chin that quantifies (through experimental data) the efficacy of different methods to mitigate electrostatic-related disruptions. Eric is a FIRST alumnus and was a summer engineering intern for 2018. His paper can be found here.