Question about carts

[Jon Stratis]

Originally Posted by Adamz_

if you don't mind my asking, what did did you use for the top of the cart, and also the internal support?

It's an old butchers block. The support is exactly what you see in the pictures - 1" plywood. No other support needed!

[sg999]

I'm not sure if this will help you, but I remember seeing a rather avant garde cart at the NYC regional last year. It was essentially a low-ish store bought tool chest with wood blocks fixed onto it to prop the robot up and handlebars. Now, as to the 4 castors vs. 2 fixed 2 steering arguement, we've recently been using 4 castors. We do have an older robot cart that has 2 fixed and 2 steering wheels, but even getting it out of our storage area is a huge hassle, so if you can, try for 4 castors. The cart moving on us has never really been a problem, as there's usually something lying around we can use as brakes. That said, our old robot cart is also on the chunkier side, while our current robot cart is more minimalist.

[Patrick Flynn]

I believe the OP is looking for a tool chest/ work bench cart. Not a robot cart, Given that I'd recommend checking out MOE's (365) pit set up. I believe they have their CAD models and material lists posted on their website.

340 Build a battery/ bumper cart, that works really well. Its basically just a two wheeled dolly, with some added compartments for batteries and bumpers. One of the huge benefits of a system like this is when your testing or practicing in a gym you can easily wheel down the whole cart of batteries and plug them in. If all your chargers are contained in the work benched you have to wheel down and set the whole system up to be much use.

I can't find a great picture of the battery cart. But i've attached what i have if you want more information I can get you in touch with someone. https://www.facebook.com/photo.php?f...type=3&theater

[EricH]

Originally Posted by chmconkling

Deep cycle batteries are not allowed in the event. Some regionals don't care but the one I was a safety advisor at, one team wanted to use one and we had to end up taking it from them.

Got a source? Neither the FRC Administrative Manual nor the FIRST Safety Manual says anything about deep-cycle batteries that I can find. On the robot, sure--everyone has to use the same batteries, and that's in the rules. Not on the robot, I see nothing at all to prevent someone from bringing one in, barring safety concerns (and if the battery is handled properly, not a concern).

[MrBasse]

Originally Posted by chmconkling

Deep cycle batteries are not allowed in the event. Some regionals don't care but the one I was a safety advisor at, one team wanted to use one and we had to end up taking it from them.

I'd also like a source on this. We have a lawn tractor battery and a UPS in our cart that charges in the pits with a standard computer power cable. We use the battery to provide power for our UPS and the UPS to charge our driver station as well as an electric linear actuator that lifts our robot from 18" off the ground to 36" or anywhere in between. This makes our robot cart a huge resource for us in the pits for working on the robot at a comfortable height, but has also proved to be an amazing resource during eliminations for keeping our DS charged and ready. We have even loaned our cart to other teams to work on their robots during eliminations.

[techhelpbb]

Best way to be absolutely sure about the legality of something with FIRST FRC is to ask in the official FIRST forum. I would ask early as this is a pretty straight forward question.

Generally, from what I have seen, people manage to get batteries that are not FRC legal into carts and pits as long as someone does not catch it. That is not exactly the most reliable tactic in the end and I prefer not to encourage people to find ways to stash things that really could be dangerous if done improperly or with people unaware.

[EricH]

Originally Posted by techhelpbb

Best way to be absolutely sure about the legality of something with FIRST FRC is to ask in the official FIRST forum. I would ask early as this is a pretty straight forward question.

Generally, from what I have seen, people manage to get batteries that are not FRC legal into carts and pits as long as someone does not catch it. That is not exactly the most reliable tactic in the end and I prefer not to encourage people to find ways to stash things that really could be dangerous if done improperly or with people unaware.

You are implying that having a non-FRC-legal battery anywhere in the venue is illegal*. This is simply not stated anywhere in the rules. Because it is not stated as illegal, it should be considered to be legal** until an official source--including Q&A--says otherwise. Which is why two people have asked for a source for the illegality ruling at one event.

The above does NOT apply to batteries used to power the ROBOT, because that is specifically covered by the Robot Rules as illegal.


*Besides the obvious laptop/cell phone/camera/other integrated batteries that aren't in a prohibited device, of course.
**Unsafe should be considered to be illegal, per the rules. Also note that this approach follows the same approach as the rest of the rules--if an item/action is not prohibited, it is permitted.

[techhelpbb]

Originally Posted by EricH

**Unsafe should be considered to be illegal, per the rules. Also note that this approach follows the same approach as the rest of the rules--if an item/action is not prohibited, it is permitted.

Define 'unsafe'?

The robot carts do not have an Earth ground...is that unsafe? Some would say yes if there's an inverter.

A top terminal battery could easily have something fall on the terminals...does that make it unsafe all the time? Some might say yes.

If the battery is not maintenance free is it more or less safe? Some could argue this point.

So the risk you take here is that your idea of 'safe' is not someone else's idea of 'safe'.

As far as something that is not explicitly denied being permitted within a FIRST venue:
A safety inspector can undo that in a blink of an eye.
I've seen it often enough not to take it for granted.

In point of fact if we entrust the safety people with the call on that you might get a different result from venue to venue.
I doubt you'd like to have a cart that is legal until say Championship then you have to take it apart.

The best way to 'settle' this is to get an official statement from FIRST.
Not from me or another volunteer.
Then you can point to the simple to ask question and say: I respectfully disagree.

After all this is FIRST's brand at stake here.
Also please recognize that FIRST trains several volunteer roles.
It would be to FIRST's benefit to provide training that suits the actual job requirement.
If FIRST is going to allow other large batteries in use at the venues they should know to update their training.
FIRST might even need to include a hazmat clean up kit in their spare parts kit.

Also there may be legality issues in some jurisdictions about certain kinds of batteries in certain quantity within a highly populated structure like a venue. Though, off hand, I can't think of any in New Jersey.

[EricH]

Originally Posted by techhelpbb

Define 'unsafe'?

The robot carts do not have an Earth ground...is that unsafe? Some would say yes.

Might I also point out that this statement also applies to the robot itself?

The best way to 'settle' this is to get an official statement from FIRST.
Not from me or another volunteer.
Then you can point to the simple to ask question and say: I respectfully disagree.

I agree with this, just for the record.

[techhelpbb]

Originally Posted by EricH

Might I also point out that this statement also applies to the robot itself?
I agree with this, just for the record.

This is quite true. However the robots are generally voltage limited because of the bypass diodes on the motors (this would be the only legal source I can think of that would generate a large voltage non-static pulse).

A large battery on a cart would encourage things like 110VAC inverters.

Even though I have a battery to charge a laptop I use an automotive laptop charger it's a DC/DC converter and relatively sealed.

If we start with lots of 110VAC inverters next there will be outlet strips and outlet strips plugged into outlet strips (bad idea).

This is not really up to me and I don't want it to be.
FIRST should do their due diligence and make the call.

There are what? 3 topics on this. Clearly it's important enough someone should just ask officially.
The sooner the better really. While there's lots of time to alter course.

[mman1506]

I am in no way trying to give an official response but I'm going to give my input from experience. We carried the deep cycle to the driver stations to keep are crummy laptop charged. It was also used charge batteries on the cart with a DC/DC charger.

At are first regional (GTRE) we asked the safety inspector about the deep cycle. He said its fine but he would like us to cover the terminals to prevent shorts. Another safety inspector requested that we put the battery in a box for our next regional because it looked unsightly on the field.

In response to this we built a nice looking case out of wood for Waterloo. At the comp we asked the safety inspector about the deep cycle and he awarded us safety tokens for the case. A second inspector later awarded us more safety tokens for the case.

[Racer26]

During my time with 1075, we had a custom motorized forklift-cart, which had 2 large deep-cycle marine batteries powering it, (and a compressor, and the programming laptop, and, and, and)

It made appearances at GTR and Waterloo, and while the safety advisors DID have lots to say about it, we'd pre-emptively quelled most of their concerns by having numerous lockouts. The cart would not move, unless the driver was seated in the driver's seat AND was pushing TWO lockout buttons on the joystick, AND the front bumper of the cart was not touching something. Additionally, it had a horn and rotating light (ca. 2003) for alerting people of its presence, and a team of people who would keep the path clear for it when moving. The batteries it carried were never considered to be a concern (though they were reasonably contained by its body).

[BrendanB]

Originally Posted by Racer26

During my time with 1075, we had a custom motorized forklift-cart, which had 2 large deep-cycle marine batteries powering it, (and a compressor, and the programming laptop, and, and, and)

It made appearances at GTR and Waterloo, and while the safety advisors DID have lots to say about it, we'd pre-emptively quelled most of their concerns by having numerous lockouts. The cart would not move, unless the driver was seated in the driver's seat AND was pushing TWO lockout buttons on the joystick, AND the front bumper of the cart was not touching something. Additionally, it had a horn and rotating light (ca. 2003) for alerting people of its presence, and a team of people who would keep the path clear for it when moving. The batteries it carried were never considered to be a concern (though they were reasonably contained by its body).

I remember something like this at GTR in 2005 although I thought it was 1305 who had the forklift driving cart. It was really cool!

[Racer26]

Originally Posted by BrendanB

I remember something like this at GTR in 2005 although I thought it was 1305 who had the forklift driving cart. It was really cool!

1075's was built for the 2008 season.

I can't remember who all has had a powered cart at GTR. There have been several teams, and I know 2013 is among them.

[Alan Anderson]

Originally Posted by techhelpbb

As far as something that is not explicitly denied being permitted within a FIRST venue:
A safety inspector can undo that in a blink of an eye.
I've seen it often enough not to take it for granted.

I think this is a problem. They are supposed to be Safety Advisors. Not inspectors. Unless they can point to a rule (either in the FRC manual, the venue guidelines, or something like the NEC), I do not believe their opinions should be considered any more binding than those of any other volunteer.

I have seen a Safety Advisor tell a student he must wear gloves when using a power drill. I have had Safety Advisors tell me they wanted to encourage the practice of continuously shouting "Robot!" when moving a robot anywhere outside a pit. I do not take them for granted, but neither do I take them as law.