Wiring in general help

[Mark McLeod]

Let me emphasize an aspect of electronics placement that 1726 does very well.

Make every status light easily visible from some distance away from the robot!

Both you and field personnel can instantly tell what's gone wrong on a robot by being able to effortlessly see what the status lights are there to tell you.

I can't count the number of trivial problems that have killed robots and were harder to diagnose than they had to be just because the simple status lights were buried in the bowels of the robot.

P.S.
Almost as bad is quickly diagnosing a problem, only to have the drive team unable to reach the malfunctioning part to fix it before a match has to start.
Don't bolt covers on or require the disassembly of the robot just to be able to plug a camera back in and stop the robot code from crashing due to an unhandled exception.

[MrForbes]

Keep the FTA happy...he is here to help you!

[Ben Martin]

We usually wire as we're building and fabricating the rest of the robot--i.e. as soon as the chassis is built, it gets wired immediately. This helps testing get done quicker. Components are mixed in wherever there is space, and sensors are designed in during the CAD process.

To help keep it clean, we run some wire in tube structure, use a variety of colors for both labels and wires, and keep it retained with zip ties and wire sheaths.

For us, there is no dedicated electrical team--wiring is done by basically everybody. The wire map is pretty clear and consistent from year-to-year, so it's usually a "just get it done" task as opposed to something that is incredibly planned.

[philso]

Originally Posted by Jhstorm

I agree with what everyone else was saying. IMO, the most important parts for cleaner wiring are having an electrical sub-team,planning out where everything goes ahead of time, and most importantly leaving time for wiring, if possible. This past year, once we had the basic dimensions of the drivebase, a few people on the electrical sub-team CADed out an electrical pan and did placement of where all the components would be. It ended up helping greatly. As this was my first year on the electrical team, the thing that helped me the most was doing wiring during off-season. We had to rebuild our 2013 robot and I ended up getting practice by doing the pwm crimps for the old bot. If there are things needing to be wired during off-season, maybe let your newer students practice. Just some thoughts...

Here's a article I found about some wiring for robotics that might help. https://frcdesigns.com/2015/07/22/fr...rsus-function/

And also don't be afraid to use a plethora of zipties, fasteners, etc.

The Electrical Sub-Team should be reviewing the CAD to ensure that the design allows sufficient space for the electrical (and pneumatic) components AND sufficient space to install and service those components. They need to speak up and veto designs that do not allow easy access to critical components. I have seen many beautiful CAD designs that cannot be built and/or cannot be repaired easily so they are essentially worthless.

Time spent planning your electrical (and pneumatic) system and time spent doing a good quality construction job is an investment that will pay you back in the form of fewer failures, easier and faster repairs during your competition season.

Here is a link to the "Electrical Layout & Construction" presentation I gave at the local Mock Kickoff last fall. It is based on many years of professional experience in mass manufacturing of electrical equipment. It may give you some good ideas on how to lay out your electrical system.

http://www.chiefdelphi.com/media/papers/3177?

Probably the two biggest problems I have found in our robots and the robots of teams we help at competitions are bad crimps and loose (screw) connections. Both can leave you dead on the field or cause intermittent problems like radio or RoboRio resets that will drive you crazy and cause you to lose matches. A pull test should be done immediately after each and every crimp. Screw-type terminals such as those on the batteries, the breaker and SPARK motor controllers should be tight and should not move when you push on the lugs with your fingers.

I would discourage hinged panels unless absolutely necessary. Routing the wires across the gap so that the do not impede the motion of the panel and do not get damaged by the motion of the panel is tricky. We avoid such practices at work for this reason. Often some time spent thinking will result in alternatives.

[GeeTwo]

Originally Posted by Mark McLeod

Make every status light easily visible from some distance away from the robot!

YES, YES, YES! Hidden status lights are the surest clues to poor wiring design. Hidden wires are about a half step behind - make your wires are easily visible and traceable.

[davidaly46]

148 design philosophy always centers on function, but form is not too far behind. From my years on pit crew and build team, here are some handy things i would recommend:

- NEVER make a wiring decision that could compromise the function of the system just to make it look a little better.

- Label.....label...label..label. LABEL!

- Use your time spent prototyping to get a feel for how your electrical system will come together, prototyping helps in more ways than just mechanical.

- Building a flexible system should be a high priority. Making extremely long runs through mechanical systems that have the potential to be replaced often, or even worse are designed to be removable, will make changes to the robot even harder. Liberal but efficient use of push and ring terminals will make these situations almost a breeze (if such a thing exists in FRC).

- Having a dedicated electrical team, or "sparkies" as they are referred to on 148, can be HUGELY beneficial. One or two mentors and a handful of students focusing on electrical/pneumatic systems will do wonders for your build and competition season.

- Have a dedicated section of your pit or workshop for housing electrical components and tools. This will help streamline your design and maintenance of the electrical systems.

- Using diagrams early in the build process, in my experience, tends to become rather useless. Electrical and pneumatic systems need to be dynamic in nature in order for mechanical systems, which determine much of your robot's performance, to be enhanced or changed at a moments notice. A better use of a diagram, or EE CAD file, would be to have one in your pit in order for students to become familiarized with the electrical system as the competition season progresses or for older robots whose systems wont change and just need to be maintained.

- Always carry zip-ties of a some form/shape/size in your pit as they are infinitely useful, and we have blown through hundreds at a single event. Luckily they are extremely inexpensive.

These are just a few of the big points i would tell a team looking to improve their electrical systems. I hope you think they are useful!