After working on many designs I have come up with this little guy:
I’ve managed to get the parts list price down to just under $30 (not including the 4 AA batteries or optional servo). The chassis is laser cut and I have shared the vector file so anyone can make it. The entire chassis will fit on an 8.5″ x 11″ sheet of paper and is made to be cut from 1/8″ materiel.
I do have plans to design an even smaller and cheaper ($20) bot, but i figured this $35 ish bot would be a good start for anyone who would like to test it out.