The Old Bike

The Old Bike is the current test platform of the Cornell Autonomous Bicycle Team. It is a converted folding bicycle developed by Andy Ruina's lab.

Mechanical Design

Front Motor Enclosure wip.

The enclosure sitting on the front of the bike is one of the main components of the bike. It serves two primary purposes: holding the motor in the correct position and protecting the motor from damage. The motor also notably must be in line with the axis of the wheel.

The current enclosure was created by welding a circular steel plate to the intersection of the head tube, top tube, and seat tube. This acted effectively as a base for the entire enclosure. The welded plate supports all of the weight of the detailed enclosure and subsequently any produced torque. The leveling of the head tube, from the inclusion of the steel base, allowed for direct access to the fork. In lieu of a stem, a rod was placed inside of the exposed fork and bolted at its end to prevent rotation. The insert was threaded on its bottom end to interface with the fork, and was connected to a coupling at its top. This coupling connects to the bottom end of the encoder that is positioned above it. The top of the encoder (I assume WIP take this out if its wrong thanks) then couples with the drive shaft of the motor. This allows for the power from the motor to be translated down to the fork and effectively control the bike's direction.

The surrounding components of this motion are also important. An orthogonal plate was placed directly above the original base plate to correct any offset, from the fork, caused by the placement of the steel base. This plate was connected directly to the base plate with nuts and bolts. Proceeding this is a plate that was added to stabilize the encoder, and two more were added to constrain the motor. Between these plates, four long threaded steel rods and an assortment of nuts were used to connect the plates to mesh the system.