[JesseK]

Couple more questions:

Could the 1.5" bore piston be replaced with 2 separate 3/4" bore pistons that are identically mounted but move in opposite directions to achieve the same effect?

Can the omnis be replace with traction wheels for more traction or is there too much skid when the wheels orthogonally rotate 90 degrees while the robot is at speed?

The picture of the under carriage that shows the linkage is great by the way. I noticed at the end of the video one of the guys saying that the linkages were flexing when under power -- perhaps you could replace the main linkages with angle aluminum and simply cut one side of the angle down to where it's a skinny "L" to alleviate this problem. You could also reduce the stress on the first 2 linkage bars by going to a 2 piston setup that uses roughly the same amount of air. However, you know better than I do if you need a 1.5" bore piston to give you enough force in the first place.