FIRST Robotics Competition Blog

Dear Teams:

We’ve been invited to share some thoughts, observations, and recommendations as your Chief Robot Inspectors. We’re excited to share with you, and plan to do so in two parts. This is Part 1, and we’ll follow up with Part 2 shortly. Part 1 is mostly tactical; we wanted to share things to look for as you start to transition from “build” to “compete.”

While all the robot construction rules (Section 9) of the Manual are important, here’s a list of some items Inspectors commonly find and often cause the most headache for teams because they can take significant time to fix at the competition. The Inspectors are there to help the teams and want to get them ready for the field as fast as possible. To help you prepare, the robot inspection checklist is published here. It is the exact checklist the Inspectors use. Please “pre-inspect” your robot by reviewing this checklist before you go to competition so you can correct any issues you find while you have the time and resources to better address them before the stresses of competition.

• Overweight (R103) and over size (R104 & R105) robots. These can be difficult and time consuming to remedy at competition, so make sure to get a firm handle on your robot’s size and weight (if you can) before you get to your event(s).

• Robots that overhang their FRAME PERIMETER in the STARTING CONFIGURATION (R102). Make sure your robot can fit within the vertical projections of your FRAME PERIMETER while in its STARTING CONFIGURATION.

• BUMPERS (Section 9.4) are a frequent sources of inspection issues. The most common issues are:
  • waiting to build BUMPERS until the event – rules-compliant bumpers take time to make and securely attach to your FRAME PERIMETER. Include bumpers in the robot design early on. Keep in mind how bumpers affect robot interaction with game pieces.
  • BUMPERS are too short (<6”) from each corner of the robot. Study R401 and the figures carefully. Those diagrams provide illustrations of “OK” and “NOT OK”. Keep in mind that a BUMPER includes the wood, pool noodles, and the cloth covering so there must be at least 6” of all three extending from each corner of your robot (unless a side of your robot is less than 12” and then the entire side must be protected by a BUMPER).
  • BUMPERS must stay in the BUMPER ZONE (<7.5” from the floor) (R402).
  • BUMPERS must be securely attached (R408-G) and can be changed quickly (R404).
  • BUMPER have a weight limit, too! (15 lbs) (R407)
  • BUMPERS must be made with 5 in. +/-0.5 in. tall plywood, Oriented Strand Board (OSB), or solid wood (except balsa) (R408). Particle Board and Medium Density Fiber Board (MDF) are not likely to stand up to the rigors of game play and are not suitable. R408 defines the BUMPER construction requirements including an illustrative cross-sectional diagram (Figure 9-7).
  • BUMPERS must be supported by the structure of your robot (R410). The intent is to provide structural backing for the wood to limit failures and maintain the protective integrity of the BUMPERS. Please study Figure 9-9 carefully and make sure your robot complies with the ¼ in. gap limitations and the 8 in. open span limitations.
• Motors (Section 9.5) – Make sure all the motors you are using on your robot are included in R501 – Table 9-1. Think about any motors that may be a part of a COTS device you purchased (such as a linear actuator or winch). Those motors need to be on the allowed motor list in Table 9-1. Some motors must be on their own motor controller, other motor controllers may have two motors (Table 9-2).
• Batteries (R601 – R607) – Only one main battery is allowed, and it must be of a specific size. Lithium or other chemistry main batteries are not allowed, only sealed lead acid (SLA) (R601). Make sure all your battery chargers have Anderson SB connectors installed (R603). You will likely have to install those yourself. Jamming alligator clips into the Anderson SB connectors on the batteries is very unsafe and not allowed. Make sure your batteries are securely attached to the robot (R606) and the terminals are insulated with electrical tape or heat shrink (R607). Batteries are considered secure if the robot could be turned over or placed in any orientation and the battery remains firmly in its intended mounting location. Pretend you are going to turn your robot upside down and shake it. Will the battery stay put or come loose and potentially fall out?
• Electrical wiring – Pay close attention to the electrical rules in section 9.6. Give your main breaker placement careful consideration. It must be “quickly and safely accessible from the exterior of the robot” (R612). You shouldn’t have to stick your hand through mechanisms on your robot to reach the main breaker buried deep inside your robot or have to open access panels etc. to get to it. You also want to protect it from accidentally being turned off during interactions with other robots or game pieces.
• Wire gauge and breaker size is very important and inspectors will look closely at this (R621 – R622). Make sure your robot complies with those rules as well as the wire color rules (R624). Make sure your intermediate connectors are appropriately sized as well (R623).
• If you are using pneumatics, all the components should be used in their original, out of the packaging, unmodified state with very few allowed exceptions (R803). Only use pneumatic components that are listed in R804. Make sure you have the pneumatics components shown in R805 at a minimum. If you haven’t used pneumatics in a few years, please note that the air compressor must now be “on board” (R806). “Off board” compressors are no longer allowed. If you are using a pressure relief valve that can be adjusted, you must adjust it to vent around 125 psi per R811. Instructions for how to do that are on page 15 of the Pneumatics Manual.

Thank you for taking the time to review this list, and we hope it gives you some insight into what we see at events.

See you soon for Part 2 of Inspection Reflection.

Have a great weekend.