5" robotic platform, setup for picaxe or arduino with sonar ranging mast. This one currently does obstacle avoidance. 90deg radian etched into the top plate to make turn calibration far easier. ttf file provided so the text will display correctly - install before you cut. Many battery configurations possible, including lipo (with a regulator) - the deck is spaced to accommodate a large range of power sources. Designed and made in response to the poorly made/designed commercial offerings - this thing uses I-Beam construction - you can stand on it. Nice platform to pickup and run with, applicable to many configurations and adaptable to multiple purposes. Cut files provided in cdr and dxf format - material is 4mm (.166) acrylic. I have placement holes for both picaxe and arduino in the file, use either both, or a controller of your choice - the platform is large enough to support several configurations. Offset ranging mast is provided with cutouts for the ping (what I had on hand), but I put placement holes for several popular models on there as well - tried to make it as universal as possible. Standard IR sensors should fit if you choose to go that route. Motor configuration is for a Tamiya 70097 motor/gearbox combo - placement holes are in the chassis for either the high or low ratio build configuration of the gearbox. Wheels are tamiya 70145's. Standard servo or micro servo with adaptor plate (in the file).