We're trying to lose weight...
 

We're over weight by quite a lot and were wondering if we could take out some of the unused cRIO module-thingies...? They don't seem to really serve a purpose that I can see... unless there's like some base code that runs in them in the background that I don't know about....? We weighed them and with the three extras removed we could lose around a pound, which would be good....

Re: We're trying to lose weight...
 

The only modules that you need to leave installed on the cRIO are the 9201 Analog module in slot 1 with the battery monitoring jumper (<R64>) and the Digital module in slot 4 with the sidecar attached to run the Robot Signal Light <R58>.

All other modules can be removed if your team is not using them.

Re: We're trying to lose weight...
 

How much is quite a lot?

Re: We're trying to lose weight...
 

I see no problem with removing the extra cRIO slot things, but how much overweight are you exactly?

Re: We're trying to lose weight...
 

Just in case:

Remember, the battery + bumpers are not weighed. :)

Re: We're trying to lose weight...
 

Yeah we're still like eleven pounds over last time it was counted... And that was without the bumpers and battery. > . > Been careful not to add too much stuff on it from the beginning, but didn't take into account all the lexane or whatevertheheckit'scalled stuff that we had to put around the electrical board and all, which is what's going to put us over....

Re: We're trying to lose weight...
 

For the future, you should remember to plan out your weight from the beginning of the season and the design process. Allot for the drivetrain, the electronics, and everything else you're planning to add. Try to keep the estimated total around 100 lbs because you're always going to end up needing extra weight in the end. (:

For now, if removing the unused modules is only saving about a pound, you should work through the entire robot design with the team and see where you can save weight.

Re: We're trying to lose weight...
 

Does your team have an air compressor on your robot? If yes you could consider removing it if you can find a way to have enough air for an entire match stored in your air tanks. Also you may want to consider removing air tanks if possible.
Another thing you may want to consider if you are using an Andymark toughbox or an Andymark supershifter is converting the large spacer block to aluminum standoff spacers.
If these solutions do not apply or are not sufficient enough, to help us help you can you please post a picture of your robot so we can see what other lightening options are available?

Re: We're trying to lose weight...
 

11 pounds of lexan is a LOT of lexan. Our basket has solid lexan sides right now and weights in at 10.6 pounds. I think it might be some other things that put you overweight, or you need to check your weight estimates.

Wetzel

Re: We're trying to lose weight...
 

Some general weight loss tips:

The accumulation of steel nuts, bolts and washers can be significant. Since robots cannot extend past the bumper perimeter this year, you may find that 1/8" aluminum rivets will suffice to fasten surfaces together that won't provide much structural strength. Aluminum bolts are lighter but more expensive, though my team has never used them. If you're using a lot of corner brackets, those can be pretty bulky. You could buy some 1/8" thick aluminum strap, 1" or 2" wide, drill holes and/or bend into an L, and they will do a good job in many instances. As far as aluminum bar stock, T-slot extruded aluminum is about 2 feet per pound, whereas hollow square tubing is about 3 feet per pound (both at 1" square).

I don't know how thick the lexan you're using is, but to mount and shield your electronics you can probably go as thin as 1/8". This is the first year that my team has varied from 1/4", we are using some 1/8" thick and some 1/2" thick for places we need the strength (1/2" thick lexan is still lighter than 1/4" thick aluminum plate, methinks).

Finally, there are always good old speed holes. Just don't go overboard and damage the structural integrity. Figure out the volume you'd be drilling away, look up the density of the material, and think if it would be worth it.

Overall, since robots cannot extend past the bumper perimeter, my team has the feeling that we can be a little less RTAD (Robust To A Degree).

Re: We're trying to lose weight...
 

another thing you can do is bore out the center of the toughbox axles, you can save a little that way, but you need a very good drill press for that. also this year the wheels do not need 6 of the screws to hold them to a hub or a sprocket, because you can not torque the wheels very much. we only have 3 bolts holding the wheels to the sprockets. another thing you can do is step down to 1/4 pitch chain.

Re: We're trying to lose weight...
 

Lots of great suggestions, plus you have two weeks still to figure it out!

Pictures of your robot would be a great help, if you are looking for more specific ideas about easy ways to lose weight.

Re: We're trying to lose weight...
 

We have used them in the past on 461, and it does help a bit, but you have to be very careful--they are quite a bit weaker than their steel counterparts, so you want to be careful to only put them in places where the load won't overwhelm them.

Re: We're trying to lose weight...
 

I'm not sure what it's called but there is a plastic material that is in a cardboard like arrangement (two sheets with vertical supports in between). My team used this last year to save wight it weights 1/5th as much as lexane (used before). That should save some weight. (6 pounds roughly) Then you need to trim about 2 pounds...

Re: We're trying to lose weight...
 

Along with the types of bolts, think about the length as well. If you only need a 1" bolt for full engagement with a nut, there is no reason to have a bolt longer than 1". You can either shorten the bolt by replacing it or taking a hacksaw and elbow grease to it.