Mounting the Robo-rio using Zip-ties?

[electrical238]

Hi, I'm from team 238 and I've been Trying to figure out the mounting rules for mounting the core electronics. the Robo-rio is giving me some problems for the fact that there are small rectangular holes by the 4 corners of the device. are you meant to put zip-ties through there? I just don't know because last year's rules said that you cant mount anything except for wires, using zip-ties. Thanks.

[mman1506]

Originally Posted by electrical238

I just don't know because last year's rules said that you cant mount anything except for wires, using zip-ties. Thanks.

Where did it say that?

[otherguy]

The holes you mention are for zip ties.
There's some images illustrating this here: http://wildstang.org/blog/?p=108

To my knowledge there is no rule prohibiting this method of attachment.

[Zekoku]

If you don't like using zip ties my team has found that wall hangers work well. Otherwise there is no rules against it.

[FrankJ]

We are using zip ties to mount the RoboRIO on our test chassis. Works great.

[Christopher149]

The screensteps documentation suggests dual-lock, which is what we are using for electrical components. Should be solid and doesn't require any holes.

[Jon Stratis]

In alpha and beta testing, we used zip ties to hold the roboRIO down without issue. We also used velcro on a different one, again without issue. Given the lack of defense in this game, there shouldn't be any big impacts that could cause it to go flying!

[matthewdenny]

I think a 40 lb strength zip tie will fit in the hole. How many g's woild the robo rio have to experience to break 4 of them? Would anything else on the robot still be functional after that?

[cgmv123]

Originally Posted by matthewdenny

I think a 40 lb strength zip tie will fit in the hole. How many g's woild the robo rio have to experience to break 4 of them?

The roboRIO is listed at 11.64 ounces, so about 220 G's if you believe the strength ratings of the zip tie, but strength ratings are often very conservative.

[electrical238]

Thanks guy's, I just said that because last year at a competition we got in trouble with the pits for using zipties for our festos.

[FrankJ]

Originally Posted by electrical238

Thanks guy's, I just said that because last year at a competition we got in trouble with the pits for using zipties for our festos.

If this happens again, politely & with the utmost GP point out the field is largely assembled with zip ties & Velcro.

In more seriousness. Although there are ways not to do it, zip ties are perfectly acceptable to use as a fastener unless there is a specific rule against it. If is an inspector questioning this, I would politely ask for a second opinion and the rule against it.

[dtengineering]

Originally Posted by electrical238

Thanks guy's, I just said that because last year at a competition we got in trouble with the pits for using zipties for our festos.

I know when I'm inspecting that if I see a team with something that is rules compliant, but that might interfere with robot reliability that I'll suggest a way to make an improvement.

"This isn't in the rules, and you don't have to change this..." is usually how I begin and, "so that's just a suggestion and it is entirely up to you. This is not an inspection item." is usually how I end. But if someone only heard the middle section of what I was saying... or if the story got relayed to them without the beginning and end parts... then it would be possible for them to think that whatever it is that I am suggesting is an inspection item.

Depending on how something is ziptied, I might make a suggestion on other ways to mount it. But depending on how something is bolted down I might make a suggestion, too. For instance, "I see you've used steel screws to bolt down your speed controllers and electronics. That is perfectly fine and within the rules, but did you know you can save over a pound of weight by using nylon screws? Not only that, but they are non-conductive. You don't need to change anything, but you might want to think about trying that for next year if you are close to your weight limit."

A statement like that could possibly be relayed to another team member as "the inspector said to not use steel screws on the electronics board because they are conductive".

I'm not saying that an inspector didn't question your use of zipties... but maybe they were trying to be helpful? Any chance of that?

Jason

P.S. One of my favorite ways to mount certain pneumatic valves is to run a 1/16" ziptie through the mounting hole and then slide a second ziptie over the end. The "heads" of the zip tie act like the head of a screw and a nut, holding the valve in place without requiring a loop as in most ziptie mountings.

[PAR_WIG1350]

Originally Posted by dtengineering

P.S. One of my favorite ways to mount certain pneumatic valves is to run a 1/16" ziptie through the mounting hole and then slide a second ziptie over the end. The "heads" of the zip tie act like the head of a screw and a nut, holding the valve in place without requiring a loop as in most ziptie mountings.

I have done this to mount Arduino Unos. It is quite clean looking if you trim the ends well.

[pfreivald]

We have always mounted all of our electronics using industrial-strength velcro, and have never had a problem with anything coming off, despite some years playing absolutely brutal defense.

[adciv]

For our beta testing of the RoboRIO, we took our beta system to the Battle of Baltimore competition. The RIO was attached to the front frame of the robot using two zip ties to those mounts. Nothing broke. Everytime we took a hard hit, the RIO got jostled and hit the frame. We *may* have had one Analog Input come loose, but that was it.

Also, I do not recommend using only two zip ties or attachment to the frame for competition. We set it up this way to test the robustness of the system, not because we'd normally attach it this way.