Team #405

[bobzdar]

Originally Posted by Wayne Doenges

What type of servoes are you using?
Looks fast.

We're using the Hi-tech servos, when we first put it together we got too much flex in the steering so we had to switch from the 'arms' shown in the week3 pictures to the circular mounts shown in the last photos and add some corner gussets to make sure the servos stayed in place. We put about 100lbs of weight on the front end to make sure we wouldn't have an issue when loaded up and the wheels were able to steer (though on tile instead of carpet and a bit labored). Once it's moving the servos don't have to work hard, the only issue is when stationary and so far it looks like they'll be more than strong enough.

All of the parts for the drivetrain except for the rear axles and some of the plates on the back end were made using a band saw and drill press or hand tools, we just spent a lot of time discussing design before building it and it came together pretty well. The rear diff came from a gas powered RC car, the rest of the stuff was either standard kit stuff or cut from aluminum.

The whole front and rear assemblies each can come off by removing 4 screws each for easy maintainence, some of the students are working on an improved and lightened design for the front and rear that may end up in the crate if they get it done in time.

We're going to do a bunch more driving tomorrow (on carpet) so I'll try to get some video of how the steering works and see if I can post it. I already have some video but it's just some low speed testing stuff, though the driver did floor it once. It appears to be on the verge of too fast, but we'll see .

FYI, in the last pic you can see the beginnings of a different steering mechanism in case the servos don't cut it, we'll find out more tomorrow.