Chief Delphi - Crab Drive HELP!!***

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Re: Crab Drive HELP!!***

Quote:

Originally Posted by Elgin Clock (Post 671958)

Can't this team just use the Andymark Mecanum drive that is available as a COTS item?
Fabrication time of the drive wheels themselves would essentially be nothing at that point, (minus some obvious separate assembly time) and then it's just a matter of waiting for it to be shipped to you, mounting it on the robot, and then having drivers practice with them.

Am I missing something here with my suggestion? :confused:

Sort of. As you pointed out, a basic mecanum isn't that mechanically challenging (although a suspension might be very important to have, depending on your frame). The software, however, can be rather tough. Not an insurmountable problem by any means (as all the mecanum robots proved last year), but it can be troublesome; just figuring out how to setup the controls for the driver can take a good bit of time.

Re: Crab Drive HELP!!***

GGCO,
Although crab drive is a great tool we don't use it all the time. It will only be incorporated into the robot design after careful consideration and playing the game. Don't make the decision at this point, play the game using chairs or tricycles or whatever and see if it is needed. If the team decides to use it then be advised that crab requires some strong mechanical attachments for both the top and botom, special handling to determine how assemblies are attached for steering, how to build a module so that both the wheel and the motor you use will fit into the space you require for turning the module and realize that crab by design puts the wheels closer to the center of the robot which compromises stability. After all of that is overcome, your drivers still need plenty of practice.
A so-so robot with lot's of practice will beat out a superior robot with no practice, every time.

As a personal request, can you include your first name in your profile? It makes it easier to respond. Thanks.

Re: Crab Drive HELP!!***

Ok, thanks all for replying! I am doing research and I am starting to see that a well designed robot/crab drive is not going to happen. I'll try to convince the rest of the team. THANKS!

Re: Crab Drive HELP!!***

My team had a crab drive system last year. It worked great and for the game this year it should be good for going around... you dont even have to turn.

But it probably would not be good for hurdling.. Its best use could most likely come from herding the ball around with it