Tips for new 'Head of Electronics'

Hi ,
I just got chosen to be head of electronics for this year.
i would like to hear if you have any tips for me about electronics and also about how to manage my team?
Thank you!

Stav

2011 - FLL student
2012- Present - FLL Mentor
2016 - FLL nantional 4th place & participated in the Philippines Islands Invitational
2016 - FRC student
2017 - Head of Electronics

Keep your wiring clean! The last thing you want the robot inspector to see is a rat’s nest in your robot.

On a similar note, does anyone have tips for CADing electronic systems? Could be 2D or 3D.

I did plenty of electronics this year on my team and I have a few pointers that I could give:
A. Don’t lose anything.
This year I managed to misplace both the PDP and the roboRio. Make sure you have shelves where you can store everything and you keep your workspace neat and organized.
B. Try to keep the electronics as far away from any parts that can move.
The last thing you want to hear is that your encoder stopped working because the wire was dangling out of the bot. I suggest using zip ties, zip tie holders (http://www.amazon.com/Startech-HC102-Adhesive-Cable-Mounts/dp/B00008VFBE ), and a lexan board with 1/4 in. holes cut into it so u can put a wire against the lexan plate and put a zip tie through the holes and around the wire to keep it secure and keep your electronics in one place.
C. Get an electronics tool box
Having all your necessary tools as well as things you know could break in one toolbox definately saves you time in the pit and build season from not knowing where you placed something. Just keep it with you at all times.
D. Check all your connections pre-match
After every match your bot’s wire connections may have been loosened. You should stay in the pit and check all your connections before the next match and run a systems check to see if everything is still working. You could also check the mechanical connections such as checking for loose bolts (shouldn’t be an issue if you used lock nuts but your never know).

As for CADing the electronics, it is definately possible as there are pre-CADed parts that you can download with a bit of searching. I definately recommend CADing the electronics before attempting to randomly put them on because the other engineers need to know before hand if you will need an extra electronics board machined out.

Fpr 3D, download the minimum competitive concept from WCP and then go into the design and save the individual modules and distribution boards. Create an electronics board or whatever you use to house your electronics by using bodies and then insert the modules onto the board. I use fusion 360 and it has a “Pipe” body that you can use for wire. Just make sure you color the positive and negative wires. For 2D, you can use Express CSP and use lines to direct your wires.
:stuck_out_tongue:

Make sure you work with your mechanical design team to ensure good placement of electronic components. You may have to be assertive with them that your roborio or pdp shouldn’t be buried and inaccessible, but be prepared to be overruled.

As for doing a schematic…yeah, you can, but in general, it will change very little between this year and next year. It may be better to study the schematic given by FIRST and make sure you understand it. You don’t have to wait until build season to learn how everything connects together and operates. During the season, your time may be better spent helping to get prototypes operating with motors with a motor controller (you’re kidding yourself if you think hooking a motor up to a battery is going to represent a real controlled system). Once prototypes are hooked up, work with the design people to work on component placement, then after you get stuff being built up, go ahead and lead the effort on wiring.

Think of things that would help you out during a competition. When you’re trying to debug something, it’s much better to have labeled wires than to try to trace a wire back to the source. Additionally, a lot of people may forget about it, but make sure your batteries are being taken care of. That means not overusing one battery over another. The goal is consistency. If you continually use and abuse one battery, eventually, your robot will perform differently with that battery than another battery (which can lead to unexpected voltage drops when loaded and can result in slow shooter speeds, stalled motors, etc.).

Tug test all your crimps. Make sure the red and yellow fuses in the PDB are fully seated. Make sure the electronics are covered when someone is filing or cutting metal in the robot – swarf is the enemy.

  • Don’t make a rats nest of wires like I did

  • Make sure that the mechanical team secures the battery very well so that it won’t break the tiptoes holding it in allowing it to knock out half the pwm wires therefor disabling half of your drivetrain like I did

  • I used some tape the ppm wires to the roboRio because the are super important and they tend to wiggle out of their place, but there is probably a way better way to secure them

  • Make sure the robot inspector doesn’t drop a battery on the Voltage Regulator Module knocking out the radio power wires disabling you for an entire match

  • Use lock tight on any talon SR screw because they will come loose.

  • if you don’t need a CAN bus then make sure you connect the roborio to the PDP with some yellow green twisted wire, not red and black like I did, (they did not like that)

  • Have the team one of those good pair of wire strippers were it automatically does the right size, those things are cool

  • Get a good set of screw drivers, I used some of my own personal iFix-it tools

  • Learn to solder, I learned the hard way

  • Lean the basics of programming just so you kinda have an understanding of how it works, ex: if you should use brake or coast depending on the programming (I was also the lead programmer so I did all of the electronics to my liking)

  • You and at least one other person check over the main important wiring before each competition, and at least check to make sure all the correct lights are on before each match

  • Get a navX-MXP, they’re super cool

    • When using the navX-MXP also connect it to a USB A port for a second source of power to protect from brownouts

Speaking of inspection, ALL your parts should be accessible for inspection. You never know when some inspector will ask to see that one thing you buried under everything else… and then you need to get it out!

Actually everything was perfectly accessible, its just that our battery wasn’t that secure on the top which he tested by yanking it out and dropping it very fast, still out fault though, we didn’t check the wires before our first match due to time restraints.

Communicate with the design team and demand enough room for well-organized electronics. The lack of electronics space on our 2013 robot is still an in-joke on my team.

On one of the teams I’ve been on, there was a space joke that went something like this…

“But [electrical mentor], we gave you three times as much space as last year!”
“Three times zero is still zero.”

“Last year”, in this case, was about a foot high, standard footprint at the time, and had cutouts on both ends and a hefty turret in the center. The robot under discussion had to go into the sizing box at an angle, and didn’t take up the entire floor, but because it was taller, the team was able to use a two-to-three deck layout.

  1. Keep wiring clean and easily accessible
  2. If your are coding too. Keep code nice and organized
  3. Stay updated on Firmware updates and rule changes
  4. Use proper gauge wire, it says which one to use in the manual for the control system

Electronics Head is a lot of fun. I direct electronics on my team. Without electronics the robot is just a pile of metal, you bring it to life.

This is coming from a former electrical lead and CSA.

  1. Read the robot rules within three days of kickoff (don’t post question to CD unless you have read all pertinent rules). Read to understand. After each rule think about what the ramification of the rule is and why the GDC included it.
  2. Read any source you can find for the hardware you are using. Read the screensteps, manuals for the electronics, including the batteries.
  3. Read the team updates and Q&A. This takes less than 15 minutes twice a week, it is worthwhile to make sure you understand the rules and the changes. Again, read to understand.
  4. Keep everything organized. I think the thread has hit this enough.
  5. Do an inspection check at the end of the season. Go through the inspection checklist (posted mid to late build season), preferably with someone else. Make sure to pay attention to the power routes for the radio, RoboRIO and PCM (if you are using it).
  6. Check with your mentors/other team leaders to make sure the electrical system is properly represented on the BOM/CAW. Make sure to check the rules (and Q&A) about if items from the kit need to be listed.
  7. Make sure all connections are secure. Push down on the red and yellow fuse in the PDP (I have pushed them until I had an imprint of them on my finger and the lexan the board was mounted on was bending and still not had them in all the way).

Always remember that you are working as part of a team. You cannot succeed unless the rest of the team does as well. It can be helpful for you to nudge other sections of the team and remind them of things they may not have noticed or may have forgotten. Commons items include creating the CAW, updating firmware, changes that were made in team updates and reviewing the inspection check list.

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This. Communication is the biggest piece of advice from me. The design team will change the room given for electronics on the robot frequently during build season, so communicate with them and adjust/keep up on those changes. Don’t make changes to the electronic system or start working on it without the approval or agreement of the design team otherwise your work will be wasted.

While we are all in a hurry near the end of build season, take your time while wiring… it pays off when your team doesn’t encounter shorts, bad crimps, etc. that hinder your robot performance later on.

  1. Take your time to do your wiring correctly and be very organized, even though it might take a while, it’ll save you in you in the long run.
    2)Color coding tape is your friend, it’ll save you from tracing wires from one end of the robot to the other.
    3)Be very careful of your sensors, I can’t tell you how many limit switches we’ve crushed and how many encoder wires got snapped.
    4)Make sure to check all your connections and make sure you tape your anderson connections. There have been quite a few matches where we were rendered partially useless because of a lose connection to a motor controller.
  2. Make a checklist for pit crew so that connections are checked between every match.
    Also just out of curiosity what sort of training projects will you be doing in the off season as head of electrical? I’m always looking for ideas

This probably goes without saying but make heavy, heavy use of the wiring guide FIRST provides you. It’ll tell you where to hook everything up and give you important details like recommended/minimum wire gauge.

I’ll also second clean, neat and most importantly pre-planned wiring. Place components in areas that minimize wire runs and make sure you allocate enough space for all the actual wires.

Wiring is fun and it’s one of the most important parts of the robot. Unfortunately there’s not much glory in doing it well, but it can be catastrophic if something goes wrong. Have fun with it and ask lots of questions if you’re unsure about something.

Thank you everybody!
I was wondering how big you think the electrical team should be?

In a perfect world you should have one lead mentor to oversee the wiring and at least two members doing the work. You need at least one lead member and then another to check the work. Try to create a system where you have a senior leading and a junior/sophomore as the secondary member.

And all of these people need to start the season knowing the capabilities of the components and also communicating with the strategy, programming, and CAD teams on a weekly basis.

On 4607 we do point to point drawings so that we can talk the other members through the process. Oh - an electrical engineer to look over your energy budget is key!

Probably the most helpful thing I’ve tried to do in my two years of electrical lead is labeling wires.

Take a labelmaker or some making tape and fold it around the wire, so a “tag” shows with some writing on it. Put a tag near where the wires plug into. It helps with wire tracking and organization.