Our Progress So Far
After passing the Gemstone team selection process, Team Autocycle (formerly SAFE-Bike) was established by 14 undergraduate students to develop an autonomous bicycle system to alleviate logistical hurdles faced by bikeshares.
Following consultation with Gemstone staff, Dr. Romel Gomez of the Department of Electrical and Computer Engineering was appointed as the faculty advisor to Team Autocycle. Dr. Gomez has been instrumental in providing the team with valuable feedback, access to resources, and sage advice.
Image Analysis and Simulation Begun
With the start of the Fall 2019 semester, Team Autocycle began work on the first stage of its research, namely developing a simulator to model the behaviour of a bicycle under various control systems and training a classifier to identify objects important for bicycle navigation in a stream of images.
Bicycle Prototype Acquired
While a proper simulation was important to save time by testing numerically prior to testing empirically, the team would soon enough need to have a physical prototype for experimentation. The chosen bicycle, christened "Otto von Cycle", would go on to be the platform for empirical testing and eventual modification for stability and navigation.
As work continued on coding the simulator and elements of the navigation system, parts of the team began work on empirical measuring the critical quantities of the bike frame such as the weight, center of mass, and moments of inertia of each of the four primary components. These values would eventually be used as parameters in the simulation and be important for properly tuning the stability control loop.
As January drew to a close, a fully functional version of the simulator was put into service. The program could simulate the behaviour of an arbitrary bicycle traversing a flat plane in its linear region subject to an arbitrary control function with arbitrary initial conditions. As the semester went on, additional features, including a PID autotuner, would be integrated into the system.
Thesis Proposal Defense
At the beginning of Spring 2020 semester Team Autocycle presented its final Thesis Proposal to a committee including Gemstone staff, the team's mentor and librarian, and an outside expert, Dr. William S. Levine of the Department of Electrical and Computer Engineering and the Institute for Systems Research. The team outlined its plans for answering their research questions through the development of the autonomous bicycle system and how these plans would be executed.
Initial Firmware Integration
With the simulation in a fully working state, it was time for the team to move on to writing code to control and sense from the actual Autocycle prototype. To that end, a drive motor was acquired, its input and controls characterized, and code for a microcontroller began to be developed to execute the tuned control loop on the physical prototype in real time.
Local Path Planning
On the navigation side of the project, with a sufficiently robust image analysis system developed it was necessary to move on to generating local paths for the bicycle that could avoid the detected obstacles. This was done using bezier curves, which after translating an obstacle into a straight line obstruction could ensure the path from the designated start and end points would not collide with any blockers.
Moving into late spring, the team began preparing the prototype chassis to be outfitted with sensing and actuation equipment. This required several modifications to the chassis itself to accommodate the drive motor's mounting on the hub and the attachment of the front handlebar control servo motor.
Machining and Actuator Integration
Going into the Fall of 2020, Team Autocycle began turning its theoretical and simulated results into practice. Having acquired appropriate actuators to exert the necessary control torques on the prototype, the team deployed and refined the stabilization firmware while also machining the required custom components to couple said actuators to the Autocycle prototype.
Do Good Showcase
In November of 2020 the team presented its findings so far to their peers, Gemstone faculty and staff, and the Do Good Institute of the University of Maryland. The presentation detailed the team's rationale for pursuing the project, its expected deliverables, the progress that has been made to achieving the team's goals, and how the project's outcome will Do Good.
Where We're Headed
Going into the winter, Team Autocycle is pursuing additional capabilities for the prototype by allowing it to remain upright and steerable even at low or zero velocities. This will allow the Autocycle to start at rest, come to speed, navigate to its destination, and come to rest again. The team is also focusing in on experimental design for assessing the efficacy of its stabilization and navigation techniques.