Tips for KitBot

[dtengineering]

Last year once we had the kitbot chassis all bolted together we took it out and had it welded up. Then we took the bolts out.

Not only did it result in an even more rigid chassis, but there was no chance of a loose bolt causing problems.

AND it saved a half pound or more of nuts bolts and washers. When we weighed in for competition we were 119.5lbs.

Ounce count.

Jason

[Peter Matteson]

Originally Posted by dtengineering

Last year once we had the kitbot chassis all bolted together we took it out and had it welded up. Then we took the bolts out.

Not only did it result in an even more rigid chassis, but there was no chance of a loose bolt causing problems.

AND it saved a half pound or more of nuts bolts and washers. When we weighed in for competition we were 119.5lbs.

We did the same and then bolted everything to the top of it so we could remove it intact and adapt the base for prototyping this year.

[Nitroxextreme]

Reinforce the axle holes by bolting on another piece of metal so that you will have 4 pieces of metal the axles go through not only 2

2 although it seems strong enough wont be...last year we didn't reinforce and after the season we had to create a new mounting bracket for the axles because the kit-bot holes were at about 150% normal size

[Andrew Blair]

The gearboxes can be very good, but be sure to assemble them with plenty of LockTite. If you don't, they will comeaprt, and they will jam. We had this happen a couple of times, and total, from three gearbox jams, we found five pieces of loose hardware inside. For some reason, the stuff in there is attracted to the gears.

Also run the gearboxes in for about ten minutes straight. They'll run a lot better for it.

[ChuckDickerson]

Originally Posted by dtengineering

Last year once we had the kitbot chassis all bolted together we took it out and had it welded up. Then we took the bolts out.

Not only did it result in an even more rigid chassis, but there was no chance of a loose bolt causing problems.

AND it saved a half pound or more of nuts bolts and washers. When we weighed in for competition we were 119.5lbs.

Ounce count.

Jason

Use caution when welding the frame. The heat from welding can distort and weaken the frame. I believe it can actually destroy the heat treatment of the frame and cause the weld to be the weak point in the frame. Also, a super rigid frame may not be a good thing. I believe the kit frame was designed to flex a little across the corners for a reason. Sort of a built in suspension. To reduce the weight of the steel fasteners in the kit frame consider using 1/4" aluminum rivets. They are strong, light and can be removed and replaced if needed.

[Gdeaver]

Definitely go for a grade 8 axle bolt. We bent a low grade bolt in testing last year.

[Tom Bottiglieri]

We assembled the Kit Bot for early program module development, but are having troubles with traction with the stock wheelchair wheels. I suppose this is from a combination of low robot weight (bare minimum for bot to run mounted), and running the bot on a slick tile floor.

Does anyone have suggestions on how to get more traction from the stock wheels? We are planning on adding more weight over the driven wheels tomorrow, and possible putting zip ties around the wheels.

[Greg Marra]

Originally Posted by Tom Bottiglieri

We assembled the Kit Bot for early program module development, but are having troubles with traction with the stock wheelchair wheels. I suppose this is from a combination of low robot weight (bare minimum for bot to run mounted), and running the bot on a slick tile floor.

Does anyone have suggestions on how to get more traction from the stock wheels? We are planning on adding more weight over the driven wheels tomorrow, and possible putting zip ties around the wheels.

Big weights. Bolt some big hunks of heavy metal to the top of the frame to get the robot up to weight.

Also, do you have any pneumatic tires you could switch in for the wheelchair ones? They tend to be much better at gripping.

[Tom Bottiglieri]

Originally Posted by Greg Marra

Big weights. Bolt some big hunks of heavy metal to the top of the frame to get the robot up to weight.

Also, do you have any pneumatic tires you could switch in for the wheelchair ones? They tend to be much better at gripping.

No, but does someone want to help me out?

[Conor Ryan]

• Try different configurations!!!-Particularly with the chassis
  • Your robot can easily turn much better if you have wheels on shorter side (28") and then use the Longer beams for your Width (38") The further you get away from that, the harder its gonna be on your robot to turn.
  • Drive Train Basics
    
    
• Review some of the documents IFI published, from their design process to their analysis after last year's usage of the kit chassis/gearbox
  
  • Chassis Design Process
  • Drive train Improvements (its a really good review of the 2005 Kit Bot, which is just about the exact same thing), side note, its one of the most interesting documents I have read in awhile.
• They mention it a few times in the Assembly manual, look into using the kit gearbox in the "Arm" Configuration, you never know you may get something handy out of it.
• Worried about nuts and bolts coming out and your bot falling apart? Use a lock washer and a Nylon Nut, its a great alternative to lock tight, and i've yet to have a problem with it.
• Most of all, have fun with the Kitbot

[ChuckDickerson]

Originally Posted by Tom Bottiglieri

We assembled the Kit Bot for early program module development, but are having troubles with traction with the stock wheelchair wheels. I suppose this is from a combination of low robot weight (bare minimum for bot to run mounted), and running the bot on a slick tile floor.

Does anyone have suggestions on how to get more traction from the stock wheels? We are planning on adding more weight over the driven wheels tomorrow, and possible putting zip ties around the wheels.

I think the zip ties will be counter productive if you are trying to increase traction. Chuck up the wheels in a lathe and turn the "crown" off to make them flat. Cut some grooves across the face of the tread. If that isn't enough wrap some better traction material (wedgetop/roughtop) around the new flat wheels and glue it.

[Biff]

Originally Posted by Tom Bottiglieri

We assembled the Kit Bot for early program module development, but are having troubles with traction with the stock wheelchair wheels. I suppose this is from a combination of low robot weight (bare minimum for bot to run mounted), and running the bot on a slick tile floor.

Does anyone have suggestions on how to get more traction from the stock wheels? We are planning on adding more weight over the driven wheels tomorrow, and possible putting zip ties around the wheels.

Two suggestions one for general info
http://www.usfirst.org/robotics/2004.../champwork.htm
check out the drive line ppt's
The second is conveyor belting. The gum rubber variety is a First staple. You can get more info from the IFI site they make the controller and also some new bolt together wheels which you pop rivet the belting to other wise teams get the wheel chair wheels lathed flat and glue the belting to the outside. Also try a search of the forums here, Hope this is helpful.

[dtengineering]

Originally Posted by Tom Bottiglieri

...I suppose this is from a combination of low robot weight (bare minimum for bot to run mounted), and running the bot on a slick tile floor.

Does anyone have suggestions on how to get more traction from the stock wheels?...

Make sure you test the robot on carpet. Our first year in the competition we had these beautiful, big pneumatic tires that worked great on the cement floor in our shop. When we got to Toronto we discovered... that our 4x4 drive couldn't turn worth a darn on the carpet! We solved the problem by reducing traction on one set of wheels by wrapping them in hard plastic duct work held on by zap straps/zip ties. Last year we did 4x4 again, but with pneumatically activated casters on one end. It would have been easier and lighter just to put omni wheels on one end.

This year... 6x6.

Jason

P.S. Skyway has some nice pneumatic wheel/tire combinations.