"Black Box" Electrical Board

[EricH]

Originally Posted by nuclearnerd

(Open question: are we allowed to use a second Anderson SB-50 connector in the line between the battery and the PDB?)

I believe the answer was "no" last year.* That being said, by being "creative" about the location of your main breaker, I think you can get away with using only one. Hint: Think (on the) outside (of) the box.



*Last year's rules do not apply to this year. OK, I said it, now the fine print: But I rather suspect that this rule/ruling will make an appearance in the rulebook/Q&A again.

[GeeTwo]

We always wait until we have at least a rough robot design before we start on the control board. The past two years, having a relatively large, flat control board worked well (belly pan, under the ball in 2014 Aerial Assist, and on the rear and low, but easily accessible for 2015 Recycle Rush). For AA, we arranged so the taller cRIO was to one side and the large parts of the pneumatics system were in the corners where they would not interfere with the ball. For RR, the roboRIO was low-profile, and we did not use any pneumatics.
In 2013 Ultimate Ascent, with the suddenly reduced frame perimeter and height (if you wanted to fit under the lowest bar on the pyramid, as we did) and complexity (throwing frisbees and climbing the pyramid were completely different!), the control board wasn't a board at all, but was (as described at the time by Allister, who was in charge of the control board) like playing 4-D tetris. Not only did he have to work in a cramped space, but it changed regularly as "team foundation" (drive and shooter) moved something, which displaced the climber, which in turn moved the controls around. If we'd had a preconceived control board, it would have been guaranteed not to fit.
In 2012 we DID lay out and install the control board after the drive was done but before the manipulators. We wound up cutting it in half to make room for the pneumatic cylinder that lifted each ball into the turret. Not pretty.
Besides, you never really know what needs to go onto the board - what if the controller you're planning to use is outlawed, or not needed? Do you really KNOW a priori whether you'll need pneumatics at all?
In short, design your control board like you design your robot -- for example, if you make advance plans for three or four basic drive systems, make advance plans for three or four basic control layouts. Then, wait until you've done your game analysis, strategy selection, and at least high-level robot design before you do your control system physical design.

[OccamzRazor]

This idea is relevant to a robotics team I was on at the university level. We used talons on this lunar rover for the NASA Lunabotics Lunar Mining Competition and they along with the rest of the sensitive electronics had to be fully enclosed because real lunar regolith (real regolith simulant used by NASA) will absolutely destroy motors, actuators, circuits, and clog any possible crevice because it also has an electrostatic charge.
https://www.youtube.com/watch?v=DaodHQC_MIo

We used these "black boxes" you see on either side to house our electrical systems and we plugged in with military grade dust proof connectors. They do work for FRC as well, but you may want to check for heat generation inside of the box and really see if simple fans will work. There are free heat conduction simulators online. It is really easy to make these boxes a nest of wires so use caution.

[logank013]

So in 2014, we had a "roll cage" like thing for our electronics. It was held down by 4 allen bolts so it was fairly easy to take off. It was a see through blue and was made of some sort of plastic (I don't know what type since I'm on electronics and didn't make the box). If I remember right, it only protected the cRio and a few other small things. I don't think it protected the talons or victors. I believe it is still on our bot so I can take a picture of it tonight if you want me to. I take it this "black box" is to protect your electronics?

P.S. I'm not sure if it was ever used in a competition. I'm pretty sure it was, but I joined in the 2015 season.

[Danimal!]

After a wiring nightmare from the previous year, our team made an electronics box. We made side mounts for 45 Amp powerpole (Anderson) connectors. This allowed the box to be detachable. We added vents and fans to the box to help with cooling, but in general, heating was not an issue. Like some of the previous posters mentioned, you want to make sure that you have easy visual access to the status LEDs. We didn't have any issues with passing inspection. In fact, most of the inspectors appreciated the effort the team made to make the wiring as clean as possible. I recommend building a prototype of the box in the off-season. We built a prototype last summer, learned a ton, and then redesigned the box we used in the 2015 season from scratch using everything that we learned. Here are the CAD files that we used for 2015 box, the prototype, and our 2015 bot (so you can see how it attached to the robot).

http://riptiderobotics.com/resources/cad/

It's a lot of work, but the effort pays off. In roughly 40 matches, our 2015 bot had zero electrical issues.

[evanperryg]

Originally Posted by GeeTwo

We always wait until we have at least a rough robot design before we start on the control board. The past two years, having a relatively large, flat control board worked well (belly pan, under the ball in 2014 Aerial Assist, and on the rear and low, but easily accessible for 2015 Recycle Rush). For AA, we arranged so the taller cRIO was to one side and the large parts of the pneumatics system were in the corners where they would not interfere with the ball. For RR, the roboRIO was low-profile, and we did not use any pneumatics.
...
In short, design your control board like you design your robot -- for example, if you make advance plans for three or four basic drive systems, make advance plans for three or four basic control layouts. Then, wait until you've done your game analysis, strategy selection, and at least high-level robot design before you do your control system physical design.

These are very important things to keep in mind. Take it from someone who was given the task of CADing the entire control system while the mechanical side of the robot was still being designed- don't waste your tine designing something that seems really good when your specs are going to change in a couple days. It's not worth the 3 weeks of headaches and late nights.

[Danimal!]

I found a website that will host 3D models that can be manipulated in your browser. Here is the electronics box that 4118 designed last season.

https://skfb.ly/ITCp

[Ari423]

Originally Posted by Danimal!

I found a website that will host 3D models that can be manipulated in your browser. Here is the electronics box that 4118 designed last season.

https://skfb.ly/ITCp

You can also try grabcad.com. Its a lot more commonly used and also automatically does file sharing and version control.

[Noudvanbrunscho]

http://teamrembrandts.com/archieven/2269?fb_ref=Default

Here is our 360 view of our 'Black Box' from last year, we made it very compact and easy to take out of the robot.

[philso]

Originally Posted by evanperryg

These are very important things to keep in mind. Take it from someone who was given the task of CADing the entire control system while the mechanical side of the robot was still being designed- don't waste your tine designing something that seems really good when your specs are going to change in a couple days. It's not worth the 3 weeks of headaches and late nights.

The relatively tight packaging constraints one has to work with in FRC robots make designing after your spec is understood an imperative.

Originally Posted by Danimal!

After a wiring nightmare from the previous year, our team made an electronics box. We made side mounts for 45 Amp powerpole (Anderson) connectors. This allowed the box to be detachable. We added vents and fans to the box to help with cooling, but in general, heating was not an issue. Like some of the previous posters mentioned, you want to make sure that you have easy visual access to the status LEDs. We didn't have any issues with passing inspection. In fact, most of the inspectors appreciated the effort the team made to make the wiring as clean as possible. I recommend building a prototype of the box in the off-season. We built a prototype last summer, learned a ton, and then redesigned the box we used in the 2015 season from scratch using everything that we learned. Here are the CAD files that we used for 2015 box, the prototype, and our 2015 bot (so you can see how it attached to the robot).

http://riptiderobotics.com/resources/cad/

It's a lot of work, but the effort pays off. In roughly 40 matches, our 2015 bot had zero electrical issues.

Congratulations on the significant improvement in reliability! Please be clear though. This increase in reliability was more likely due to greater thought and care being given to the layout and construction than the fact that your control system was enclosed in a box. Since putting in place a better construction standard that includes verifying the quality of all connections (crimps) we have had only one electrical failure in the last two years. That failure was a loose crimp in an old battery cable.