Robotics Education & Competition Foundation
Inspiring students, one robot at a time.

This Q&A is now read-only

Official Q&A: VRC 2020-2021: Change Up

Usage Guidelines All Questions

LED light strip usage


5090X
16-Nov-2020

RGB Light Strips and <R13>

<R13> states that

Decorations are allowed. Teams may add non-functional decorations, provided that they do not affect Robot performance in any significant way or affect the outcome of the Match. These decorations must be in the spirit of the competition. Inspectors will have final say in what is considered “non-functional”. Unless otherwise specified below, non-functional decorations are governed by all standard Robot rules.

Say a team has an RGB light strip under their robot for decoration, and a V5 sensor in the robot that provides information to the V5 Brain regarding activity taking place inside the robot. This information is used for robot function automatically by the brain to sort game objects.

If, for decorative purposes, this sensory information was also used to set the color of the RGB lights, would this violate <R13>? The lights would not be giving the driver any information that they could not already see with their eyes, and the only purpose for this would be a cool lighting effect as the robot was scoring game objects.

An example of this is below:

www.youtube.com/watch?v=4CRX30Sa3HQ

My questions are:

  1. How would “functional” be defined for RGB light strips?

  2. Can the color of a decorative RGB light strip be set in the robot’s code that does not accept any input from sensors? i.e. the lights are a solid color, or cycling through a rainbow of colors and don’t change their pattern.

  3. Can the color of a decorative light strip be set based on sensor feedback? Remember, this wouldn’t offer any competitive advantage to the driver, and is only for use as a cool lighting effect for the audience.

  4. Can the color of a decorative light strip be set by the code based on input from a driver? i.e. a driver hits the “A” button on their controller to turn the lights green, or the “B” button to turn them yellow. Additionally, if using sensor feedback for this is ruled illegal, a similar effect could be emulated by changing the light pattern when the “score” button is pressed.

For all 4 of these questions, keep in mind that it is solely for decorative purposes, and offers no additional information to the driver that they could not have already gained from looking at the same place that the sensor is.

Answered by Game Design Committee
  1. How would “functional” be defined for RGB light strips?

As stated in R13, inspectors (and by proxy, Head Referees) will have the final say in what is considered "non-functional". We will attempt to provide some guidance in this response, but cannot provide a blanket answer that will encompass all hypothetical non-functional decorations.

The key phrase in R13 is the following:

Teams may add non-functional decorations, provided that they do not affect Robot performance in any significant way or affect the outcome of the Match.

When dealing with a rule that requires an inspector or Head Referee judgment call, we always recommend making your legality abundantly clear to the inspector responsible for making that decision. In the context of non-functional decorations, this means removing any possibility that the decorations in question could influence Robot performance or affect the outcome of the Match.

With that in mind, the differences between your questions 2-4 are ultimately irrelevant and/or still too reliant on the context of the lights, code, Robots, and Matches in question.

On one side of the judgment call spectrum, a single-color LED strip that never changes color, brightness, or pattern throughout the duration of the Match would likely not be considered "functional".

On the other side, a light which indicates that a Robot has completed a function, such as intaking a Ball, would very likely be considered "functional". These decorations are now providing visual feedback to the Driver that would not be present otherwise.

For all 4 of these questions, keep in mind that it is solely for decorative purposes, and offers no additional information to the driver that they could not have already gained from looking at the same place that the sensor is.

Ultimately, this statement is a subjective opinion, not an objective statement of fact. Hypothetically, envision a scenario where the Robot in question was being blocked by an opponent, such that the Driver could not see their mechanism, but could still see the glow/reflection of the decorative lights.

To avoid any confusion or disputes with inspectors and Head Referees, we would strongly advise not tying any non-functional lighting decorations to Robot states, interactions, sensor feedback, or Driver input.