"The Little Things" - Helpful hints for all

[yash101]

Originally Posted by jijiglobe

Ziptie-ing batteries is a big deal. it seems like the connectors are so tight that they'd never get unplugged but we lost an eliminations match because of it. It may actually have saved us the next game though because our opponents wasted the entire match trying to knock our battery out (we ziptied it though).

With Team 1165's great engineering skills, we designed a battery holder that snugly held the battery while allowing it to be completely accessible. Also, I prefer velcro over zip ties because velcro is easier to use when you want to reuse it. Even better of an idea, though also dangerous, would be to place a verry powerful NiB magnet on the battery and the robot. If powerful enough, it will restrict the axes of movement but allow the battery to move enough so it doesn't get destroyed by the vibrations. On our battery restraint, even if it was ope, it would have protected the battery from the highest g-forces possibly (falling from the third rung)

[Chris is me]

Originally Posted by yash101

With Team 1165's great engineering skills, we designed a battery holder that snugly held the battery while allowing it to be completely accessible. Also, I prefer velcro over zip ties because velcro is easier to use when you want to reuse it. Even better of an idea, though also dangerous, would be to place a verry powerful NiB magnet on the battery and the robot. If powerful enough, it will restrict the axes of movement but allow the battery to move enough so it doesn't get destroyed by the vibrations. On our battery restraint, even if it was ope, it would have protected the battery from the highest g-forces possibly (falling from the third rung)

He's not talking about zip-tying the battery into place; he's talking about the practice of wrapping a zip tie around the Anderson connector that links the battery with the robot. This mechanically prevents the battery from being unplugged.

I don't think we should be suggesting to teams that they affix very strong magnets to their robot and battery. Among many, many other issues: How do you attach the battery to the magnet? And if you know how to do that, why can't you attach the battery to the robot that way?

[Jared]

Originally Posted by yash101

With Team 1165's great engineering skills, we designed a battery holder that snugly held the battery while allowing it to be completely accessible. Also, I prefer velcro over zip ties because velcro is easier to use when you want to reuse it. Even better of an idea, though also dangerous, would be to place a verry powerful NiB magnet on the battery and the robot. If powerful enough, it will restrict the axes of movement but allow the battery to move enough so it doesn't get destroyed by the vibrations. On our battery restraint, even if it was ope, it would have protected the battery from the highest g-forces possibly (falling from the third rung)

Reusable zip ties work really well on the battery connectors. If you spend a lot of time making a fancy battery box, the team will take it off when the robot weighs too much, so simple and light solutions are always good. However, a single zip tie is NOT STRONG ENOUGH to restrain a battery. If the robot is hit hard enough (like falling off the tower), the battery will break the zip tie, and could hit something important (like the power distribution board).
To add to the list-
Always make sure you maintain your batteries well.
Do not leave a bunch of batteries in a place where they will go from <32*F to >80*F.
Make sure that all of your team knows never to lift the batteries by the connector. Someday, the terminals will be ripped right off of the battery.

Also, don't ever charge a battery that you suspect may be damaged/dropped. The battery will expand, get stuck in your charger cart, and leak stinky acid all over the place.

[yash101]

The battery holder was a very simple design and I think it weighs ~1 pound or less. It was just a half cage of aluminum lined with foam to grip and protect the battery. This was mounted on the outside of the robot chassis, making it VERY accessible. Also, to quench any doubts we had about whether it would hold, we placed a piece of velcro on top to make sure it stays put

[DampRobot]

The thing is, you never notice how important any one of the little things until it bites you in the bud at the worst possible time.



Final 2 at CalGames. The box in the lower right of the picture is our battery box (the real battery was still attached, we drove across the field and hung with it laying on the ground). Had we put a few zipties in the box between matches, we would have likely been able to make up the 16 points that separated our alliances, and could have taken the other alliance to a third match.

[yash101]

Wow! I'm surprised there isn't battery acid all over the place. If I can get team permission, I will post a photo of our battery holder. It was bolted on!

[colin340]

-during fundraiser and off season make folks bring lunch!! and save on pizza!

[Mr. Lim]

Velcro battery connector:


Robot handles from aircraft cable and pneumatic tubing (1 at each corner of the robot):

[Mr. Lim]

Attaching square tube to plate using 3 roll pins and threaded rod:
(Also, identical drive plates so you can't mix them up on assembly - left/right/inside/outside are identical)

[Mr. Lim]

Quick release bumper mounts:

[Mr. Lim]

Drivetrain gearbox integrated between drive rails:


Chain tensioner from off-centre drilled shaft:


Quick disconnect spade terminals on speed controller:


Surgical tubing to connect encoders and pots to shafts:


Mount PDB on spacers so you can run wires UNDER it (instead of around/over it):

[Mr. Lim]

Standard pigtail lengths on every motor w/ Anderson connectors:


Extra solenoids and speed controllers on the board:
-If a solenoid fails, we swap the tubes over to the spare solenoid and change the mapping in programming. Unused spare solenoids are plugged with tubes that have been folded over and zip-tied. This is a cheap plug that doesn't leak.
-If a speed controller fails, we disconnect the motor from the failed speed controller, and run an extension wire to a spare motor controller. Because there are quick disconnect spade terminals on all speed controllers, this is can be done very quickly. Programmers then remap to the spare controller.

[Justin Montois]

Thanks a lot for posting those, just awesome stuff.

[BBray_T1296]

Originally Posted by Mr. Lim

Surgical tubing to connect encoders and pots to shafts:

Not sure how I feel about this one.

I would think the twisting slack the surgical tubing has would be a bad thing?