"Kit" might not be the best word to describe these products. They are shipped to you fully assembled, (except for electrical connections), so that you can go right to work adding your finishing touches. Leaving the armor and weapon up to you preserves maximum versatility and flexibility and it requires you to use your creativity to come up with a winning design. Start with this rugged, low-profile, mobile platform to simplify and reduce the time required to complete your project.

This kit is designed as an almost complete robot so it's easy to finish the robot within the 30-pound weight limit of the class.

This kit, (unlike the other kits), includes aluminum top and rear armor, a blue-tempered spring-steel front wedge, and custom-made battery mounts, braces, and other parts that compose all the mechanical components of a basic wedge robot. Our single-battery standard set-up leaves you over three pounds to use for your radio, for a second battery pack, or for further customization. It's also possible to remove another couple of pounds from the frame and the motors if you need even more weight.

The robot is shaped like a parallelogram. The angle on the front gives you the wedging action that makes this type of robot so effective. The front of the robot rides on a glide made from UHMW-PE for good wear resistance. The reverse angle on the rear enables the wheels to stay in contact with the floor even if the robot is tipped up 45 degrees. It's also the perfect place to put our custom battery packs because it gets most of the battery weight behind the rear axle. Weight distribution is very important in 2-wheel robots. Too much weight on the front reduces your available traction and too much weight on the rear will cause the front end to lift, or "wheelie", under acceleration. With two battery packs the weight is distributed just about perfectly with 1/3 of the weight on each of the wheels and 1/3 of the weight on the front glide.

The wheels penetrate through the top so the robot will still be mobile if it gets inverted. It won't be as effective running upside-down, but at least it won't be a knockout - you'll still have a fighting chance.

Rugged Construction
Goal number two is "battle worthy" construction. One of the keys to BioHazard's success is a bulletproof drive train that is completely housed in a square aluminum extruded tube.
The one-piece extrusion (one each for the left and right drive trains), is precision CNC machined with mounting holes for all the sprockets, wheels, and motors. Each drive component is supported on both sides of the 3" x 3" square aluminum tubing to avoid "overhung" loads.
The tubing is made from 6061-T6 aluminum alloy. The feather and light weight robots have frame tubes with 1/4" wall thickness and the middle and heavy weights have tubing with 3/8" wall thickness. BioHazard, (a heavy weight robot), uses 1/4" tubing but we wanted to offer an even stronger drivetrain to stand up to your most destructive opponents.

Drive modules include a separate two-stage speed reducer for each wheel. All the drive chains are continuous loops with no connecting links. Eliminating the connecting links increases chain strength by almost 30%. BioHazard uses #25 chain, but we wanted the drive train to be extra-strong so all our kits feature #35 chain. The sprockets, shafts, and axles are custom-made from 5140 Chromoly steel. Two different sets of sprockets are available so you have your choice of medium-fast or very fast, (details below). One of our powerful Motors mounts on each drive module and is plenty strong for any ordinary robot. Our middle and heavyweight drive modules also have mounting provisions for a second set of motors if you are looking for truly extraordinary acceleration.

The wheel assembly is made from the popular 4" Colson Performa tire. These are machined and mated to our custom hubs, bearings, and 19-tooth Chromoly sprockets. This combination weighs in at just 1.1 pounds - including the drive sprocket! We believe that this is the lowest-cost and lightest wheel/sprocket combination available. These wheels are included in all our kits but you can also order them separately. Visit our wheels section for more details.

The base plates and the bulkheads are made from 6061-T6 aluminum. The base plates are drilled and countersunk with all the mounting holes for the bulkheads, drive modules, speed controller, and several different sizes and types of batteries. All components are CNC computer machined to tight tolerances for maximum consistency and lowest cost.

One of the key features of our kits is that they are held together entirely with screws. Using screws instead of welding makes it easy to replace damaged parts. The heavyweight base plate has over 90 screw holes! The thickness of the base plates ranges from .156" for the heavy weight, down to .094" for the feather weight. Bolting the bulkheads and the drive modules to the base plate results in a very stiff structure. You can easily drill and tap holes in the drive modules to mount your own custom components

None of the sprockets hang below the bottom surface of the drive modules - not even the sprockets on the wheels. The screws are all countersunk on the underside so nothing protrudes from the smooth surface of the base plate except the rubber part of the wheels.

Tip Resistance: The wheels are positioned so that they stick out of the frame towards the front and the rear. This allows the robot to be tipped up onto its front or rear and still maintain contact between the drive wheels and the floor. This can get you out of trouble if your opponent is a wedge or a flipper. You can decide to keep this feature or cover the wheels with armor. The wheels are also positioned as close to the sides of the frame as possible so that even sideways tips will still have to be quite extreme before the frame comes in contact with the floor.

Another of BioHazard's key features is the low profile. The highest point on any of our kits (the bulkheads) is just 4.4 inches from the floor. This allows you plenty of room to build your educational project or combat weaponry on top of the kit's mobile platform without creating a robot that is unreasonably tall. A low center of gravity also makes it very difficult for your opponent to tip you over.

Ground Clearance: You can increase the ground clearance on any of our kits with a little extra machining. Contact us and we will provide detailed drawings.