Robot Cart
 

Between the transition period between bag and tag, and competition my team wants to build an all around cart design with wheels such as pneumatic. I have been tossing some ideas around but I can't seem to get any good ones. If possible does anyone have any ideas or CAD drawings for me to bounce ideas off of?

Re: Robot Cart
 

As a general tip, you should have some sort of platform that lifts the robot up for easy accessibility. Our team uses a special scissor-lift that brings the robot to a comfortable height, and we have crossbars that "jack up" the bot so we could test the drivetrain and put our hands underneath. Think about reusing the cart for years to come as well. Robot shapes and designs change, so make your cart adjustable and give it the ability to hold bumpers and other large items. Most importantly, your cart should be maneuverable and compact enough to fit through tight spaces (use swiveling casters, etc for wheels). We found this out the hard way when our original cart was too wide and too tall to fit through the doorway! Be creative, but be sure to follow the cart rules too (sadly, no music allowed on the cart).

Re: Robot Cart
 

My advice is to keep it simple. The two most important things it should do are:

• Carry the robot between pits and field, and back.
• Give you a safe and productive work surface.

Everything else is gravy.

Keep it small enough to fit in the pits and allow people to work around it. Locking wheels are helpful (but make sure all students know how to lock and unlock them). Swiveling wheels on one end and straight wheels on the other work best. And a handle at waist height for easy steering and pushing or pulling. Ropes are not so good, but better than nothing if you have a low-to-the-floor cart.

I've seen some teams with scissor lifts or pneumatic jacks. Sometimes I'm jealous, sometimes I'm glad we have a simple, solid, flat, dependable, safe surface.

Shelves and drawers are nice for carrying the operator console, bumpers or covers, some tools, spare battery, etc.

If you're using pneumatics and an offboard compressor, the cart is a good place to keep them (with a battery for the compreesor). Even if your compressor is onboard, you're allowed to pre-charge your tanks.

No matter what, it should be a fun project to work on, now that the pressure of build season if off.

Re: Robot Cart
 

We have this cart: http://www.harborfreight.com/500-lb-...ble-94822.html
It is ~$150 and is easy to raise the height

Re: Robot Cart
 

Don't forget space enough for a camping chair or folding chair of some sort as well as room for your bumpers, both sets.

Also include some basic power system, aka power strips properly rated, for your laptop, chargers for batteries and etc.

The last thing I'd add would be a cooler with water or something similar. I know some regionals are tight on food and water brought in but when the heats on, gotta keep cool.

Re: Robot Cart
 

We looked into getting that exact cart, and decided the surface was way too small. We felt it should be bigger than the robot; i.e., more than 28x38". The actual size of our cart is about 36x48", so it is a nice work surface.

Re: Robot Cart
 

Our team's cart is simple, just a folding cart fitting with a solid base of wood and some nice handles. If there was an improvement I would make on it, it would be a place to hold the driver's station. Our driver often has trouble carrying our station (which is very fancy custom acrylic and aluminum) through the crowded pits. If you can get both of those in inexpensively, I'd say it's mission accomplished.

Re: Robot Cart
 

You wouldn't happen to have a picture of it would you? This is exactly what our team wants to do.

Re: Robot Cart
 

oh no! we'd never thought to photograph the cart, so i don't have one, but it's basically this thing on the left :
http://img1.classistatic.com/cps/po/...828d0n_27.jpeg

except it has longer handles, and an attached wooden base of FIRST robot dimensions. You can slide it back and forth between a dolly and a cart for the robot. The handles are just long enough the prop the driver's station on if necessary to wheel it around, but like I said- we haven't really fixed that problem yet. :) hope that helps.

Re: Robot Cart
 

Pneumatic tires might seem like a good idea until you get to a competition and have a flat. Some of those small ones are difficult to inflate, and if you get a real leak in one, they don't roll too well. I'd stick with something that doesn't need to be inflated.

Dr. Bob

Chairman's Award is not about building the robot. Every team builds a robot.

Re: Robot Cart
 

Remember your cart needs to fit through a standard 36" doorway.

Re: Robot Cart
 

You could look into getting an AndyMark cart and customizing it.

Re: Robot Cart
 

We have an aluminum platform cart with a removable handle.

Attached to the deck are two 8020 cross bars. On top of those are two longerons. On the longerons are posts that support the robot. By adjusting the locations of the longerons and posts, we can fit the cart to each year's robot. The height of the posts are set so the robot just clears a standard doorway. If necessary, the posts can be trimmed or swapped out to increase or decrease the robot height.



As shown in the pic, the crossbars and longerons also make a convenient place to stick stuff when working on the robot.



The cart design is evolving. Last year the height was great for standing and working on the robot, but we couldn't go through doors. This year, we dropped the post height to fit through doors, and the robot ends up at the perfect height to work on while sitting in a chair.

Next step is to add stowage for the operator console, tools, and water for competitions. We had stowage for bumpers last year, but may leave them off the cart this time.

Re: Robot Cart
 

^^

Re: Robot Cart
 

I totally agree with keeping it simple, as long as the robot can be transported on the cart and is able to be suspended on the robot with stability

Re: Robot Cart
 

Todd,

Can you tell me more about the base of this cart? Did you buy it or is it all custom? I really like this design!

Re: Robot Cart
 

We made ours with 1/16 wall 1" steel square tubing that was student welded. A set of EXTRA BEEFY mecanum wheels that make it a breeze to maneuver and some nice bearings that allow it to be pushed in any direction with one finger while having 400 lbs on its bed. It can have 12 batteries on board and nice tool set. It can handle a 4" high wire bump with ease. It has adjustable rails that the robots' dead axles sit on so we cant test the drive train and easily work from under the robot. It soon will be motorized and will use 4 AM Super Shifters that have a gear taken out of them so we can shift into neutral to make it really easy to push. It'll also have underglow and headlights for loading/unloading at night. But one of my favorite feature's is that with the removal of two pins that hold a rail on, you can flip up part of the middle tray and it becomes a comfy 2 person couch (it'd be really fun at demo's!) perfect for the practice field and when our drive team is exausted. :P Still no pictures, but there coming. ::safety::

Re: Robot Cart
 

Our students built a new cart shortly after the stop build date. The design is alot like ToddF's pictures, except a bit longer and shorter (it fits under doors). They made a simple frame out of PE20 aluminum (I think thats what it was); put lexan on the bottom of the frame along with a pad so someone could climb under the robot and work (or nap; it even has an elevated piece of lexan with a headrest), we can store bumpers, balls, batteries, and/or drivers station down there too when it's queueueueing time.

The lengthwise supports are adjustable easily enough (for forward compatibility), and support the robot by the frame instead of the wheels, so the wheels can spin freely.
We also attached some PVC tubes as tool/flag holders.

Re: Robot Cart
 

Although I unfortunately don't have pics right now our cart is all custom. Our welders bent some 1 inch tubing to make a base that's wide and long enough to hold three bins plus our driver station and a battery on top of the bins, then an elevated U-shape bent from the same tubing. The U-shape is the width of the inside section of the C-Base long configuration frame, so the robot rests there. The wheels can free spin there, and we used it for testing motors often.

We have two simple lcoking casters and two fixed wheels, larger than 6 inches to get over the cord bumps at MN North Star's venue. The casters were from Minnesota Casters, a distributor in MN. Gotta love our sponsors.

Re: Robot Cart
 

We made a cart before build season this year. It is an extruded aluminum frame, covered with aluminum plate. The sides of the shelves are black powder coated aluminum with our logo cut out by waterjet. The shelves hold tools, batteries, and our charger. The handles are chrome bmx pegs and the wheels are jumbo casters that we salvaged from some huge steel trolleys donated to us by General Motors. The robot is held off of it's wheels by four pieces of extruded aluminum.