Hi

If you decide to use the A123 batteries the configuration I use is 2 4*4 cell packs 26.4v, that way one cellpro10 charger can charge the whole 32 cells at once. (BTW I think 6s LIPo packs have a nominal voltage of 22.2v)

The motors look OK, what material are the wheel hubs made of? I was thinking your 100Kg robot being flipped 2 meters in the air and landing on it's side the force on the hub is extremely high and may break the wheel. If you can find smaller wheels to fit you would lower the ratio of the drive and increase the pushing ability of the robot, plus reduce the likely damage to the wheels and gearboxes. that might help.

Bike tyres are favoured by me on almost all my machines.

I like the basic look of the 40Kg machine, it's a good place to start.

I would advise making a machine without a working weapon first, but you can design space in the robot for one to be retro-fitted once you Have a working platform.

Screw jack lifters do work but because they are normally so slow, in battle environments you rarely have chance to use them effectively. Cherub lifting arm can achieve maximum lift height in 1.5 seconds and sometimes that's too slow!

Looking forward to seeing you design

Craig