Quote:
Originally Posted by teslalab2
Hi all! I'm building a robot with my money to finalize my arduino-wifi control system. Before I spend my own money on a lemon  I want to know what drive system I want going to go with. I was wondering if any one had experience with 4 wheel X shaped omni drive. like this http://i.ytimg.com/vi/Z0lUTMBbu9A/maxresdefault.jpg
I don't want to spend money on encoders. I programmed encoders on my teams bot this year for mecanum, I just don't want that headache for this 
So basically, can I even drive in straight line with this, or is it just as bad as encoder-less mecanum?!
Thanks |
While I don't have any experience with this configuration
per se, the kinematics on the four-wheel killough drive are the same as mecanum, which we used for Aerial Assist. This means that you can use the canned "holonomic drive" class/block. For AA, we did not use encoders. We added a gyro so we could use "field coordinates", but we did not get it working for competition (it turned out to be a bad gyro). The drivers never expressed any problems getting it to drive in a straight line, in any direction. As with mecanum, you will want to balance the load across the wheels as much as possible, and I'd also recommend a flexible frame or a suspension to keep all wheels on the floor. If you are planning to take it over humps and dips and don't have some sort of suspension, expect lousy performance, including unintended rotation.