Learning Electronics

[CalTran]

So I do have general electrical experience, and when I say "definitive guide" I meant to FIRST Robotics. I got one of those 2009 FRC Control posters, and I know where things hook up, but just wondering if I need to get any more in-depth than that.

[kstl99]

Originally Posted by CalTran

So I do have general electrical experience, and when I say "definitive guide" I meant to FIRST Robotics. I got one of those 2009 FRC Control posters, and I know where things hook up, but just wondering if I need to get any more in-depth than that.

The above posts give good resources for learning electrical and electronic theory but that is different than actually wiring a robot. I recommend a video I found by Alan Skierkiewicz http://thinktank.wpi.edu/article/149. One of the few things I disagree with him about is that I like using AutoCAD Electrical to make an actual schematic (we label all wires and components with sheet and line number to be able to find it on the schematic easily). AutoCAD Electrical is available to students free at http://students.autodesk.com/?nd=register&und=624 and a copy of the schematic we used for Breakaway is here http://www.chiefdelphi.com/media/papers/2384.

The biggest thing to remember is that one loose wire connection or one unsecure wire finding its way into a chain can cause your robot to sit while the others are scoring and that is not a good feeling.

[Al Skierkiewicz]

kstl,
I have no problem with Autocad and use it almost everyday. If you have the time to draw documentation and would use it for teaching assistance, then have at it. We use the color coded tape method to remove a major stumbling block in repair. In the finals when something goes bad, you will not be looking at a schematic. You want to find that something NOW and fix it.
Of all the problems teams have with electrical on robots, improper crimps/wire terminations are the greatest. A poor crimp causes heat and termination failure. A bad termination at the PD or a power supply connector has the potential to bring down the system. If I had a nickel for every 24 volt to Crio connector I have pointed out as a problem, I could buy a nice dinner after an event. If you strip too much wire from the power wiring, cut some off so that you won't have uninsulated wires touching. If you have a whisker sticking out, either cut it off or reterminate the connector until it is right.

[kstl99]

Originally Posted by Al Skierkiewicz

kstl,
I have no problem with Autocad and use it almost everyday. If you have the time to draw documentation and would use it for teaching assistance, then have at it. We use the color coded tape method to remove a major stumbling block in repair. In the finals when something goes bad, you will not be looking at a schematic. You want to find that something NOW and fix it.

Excellent point. I think what I will do this year is both. I really hate to give up the AutoCAD Electrical schematics as they are an industry standard and really help in circuit design and in being able to understand how everything works but I can see where the color code makes things very intuitive. I will document the color code on the schematic.

I also think an experienced electrical mentor, one who has actually done a lot of wiring, is important if you can find one to help. There are so many things that can cause problems such as one strand sticking out as you mention, and so many tricks to make things go smoother that are hard to learn on your own.

[Al Skierkiewicz]

kstl,
When I mention color code I am referring to our method which color codes everything. We use the 3M color tape wheels (available from Digikey and others). Everything is coded. The motor, the motor position on the robot, the motor wiring, the speed controller, the power wiring to the speed controller, the pwm cable (both ends) the position on the sidecar, the breaker and the breaker position on the PD.
If the red motor is not moving, you look for the red controller to see if it has power. If not, you check to see that there is a red breaker in place. If the controller is powered but showing no PWM connected, you look for the red PWM cable and make sure it is connected at both ends as it is marked. It sounds harder than it is. We use a spreadsheet with the codes marked on it for communication between the software, hardware and electrical teams so we are all on the same page.

[kstl99]

It actually sounds quite logical, easy to implement an should be a good addition to the next robot we build. I will check out your video again for the details.

Thanks

[Al Skierkiewicz]

Our spreadsheet from 2007 is loaded on CD as MotorFunctions.xls

[kstl99]

Originally Posted by Al Skierkiewicz

Our spreadsheet from 2007 is loaded on CD as MotorFunctions.xls

I had a hard time finding it till I used a Google search and found it on the next to last post here. http://www.chiefdelphi.com/forums/sh...ad.php?t=70968

I hope we have helped the OP. I am always surprised at how little attention wiring gets when it can cause so many problems.

[dekker120]

If you guys need any help this spring, don't be afraid to ask. I can come out and check everything or even help wire the robot (while teaching others) if you need me to. You can PM me or email me at matthewmohler@yahoo.com if you need any help.