pic: FRC488 Chassis Coming Together

Last night, we did a quick test assembly of a gearbox and chassis to make sure there were no unseen problems cropping up before we move forward. Three of the frame rails still require a trip to the plasma cutter to have lightening patterns cut into them.

We’re behind schedule because McMaster-Carr did not ship an order we made to them on Kickoff until yesterday afternoon. That order contains most of our wheel shafts and sprockets. With luck, it arrived today.

cool. and shiney. i was half expecting a super elobrate frame. but this looks very conservitive compared to other stuff you have come up with Madison. i am going to make a jump and guess that i will see the complexity , time and weight budget used in you end effector device. Now i am super curious as to what monstrous devices this drivebase will be carring arround?

I hope that once the lightening triangles are added, it’ll seem that we spent a least a little bit too much time on things. This drive is very simple compared even to 6WD we’ve done in the past and might be my favorite so far. I can’t wait to get it finished and driving around.

The rest of the machine is designed to fit into the 5’, 110 lbs. weight class and will be using every last bit of the available space and weight in that class.

Live axles and chain-in-the-frame? Simple concepts and slick execution are the hallmarks of great engineering.:cool:

And painstaking attention to detail is how the great ones make it look easy.

The chain will run along the inside of the frame rather than in the tubing to make accessibility somewhat less of a nightmare.

This is the first time I’ve designed a robot with live axles in years and it’s not a bad way to go if you’re able to achieve a final ratio in a gearbox rather than by using chain as a final gearing stage. The hubs on large, keyed COTS sprockets are an enormous weight penalty otherwise and the main reason why I switched to dead axles in the first place.

I hope that we keep on track with simplicity this season and the rest of our mechanisms turn out to be as simple to build and operate as this drivetrain has been so far.

I also hope that our plasma cutter stops eating pieces of aluminum for breakfast, lunch and dinner. There’s nothing quite like making the same part 8 times because the plasma cutter keeps finding new, interesting ways of cutting holes in the wrong places. :slight_smile:

It looks good M.

How much bearing support do you have on each wheel? Is it a completely cantilevered system? I assume you are going to include bumpers into this system. Are you going to add cross bracing when you add your end effector for additional support. Also did you run any numbers on loads on the sides of the bot. If so what did you use for an impact load? Thanks!

My team did 2 wheels with ball casters in the cornors in Triple Play and it worked very nicely. We could turn on a dime.