Senior Capstone Project in Green Technologies: Study of Electromagnetic Braking as Prospective Enhancement of Friction-based Automotive Braking System

Senior engineering projects are the capstone of students’ educational careers, being a proof of the skills and competencies acquired as well as an important tool to assess students’ knowledge in their field of study. Capstone design courses enable students to integrate theoretical knowledge with the practical skills gained during their academic experience. Senior design projects developed by students in our department are interdisciplinary in nature and mainly address emerging or current engineering topics in areas such as manufacturing, green and renewable energies, sustainability and healthcare. The project presented in this paper addresses the need for reducing pollution by developing environmentally-friendly automotive braking systems. Conventional frictional brakes inhibit the motion of a vehicle by converting the vehicle’s kinetic energy into heat. Removing the friction between the braking elements and braking surface means the lifetime of these components would be significantly improved, which would reduce the recurring costs to the consumer over the lifetime of their vehicle and would reduce generated pollutants. [1]. This project investigated the feasibility of total or partial replacement of the frictional braking system in an automobile with a contactless electromagnetic braking system. The investigative efforts are “proofof-concept” type. The student-led team designed and built a prototype for a frictionless electromagnetic braking system by installing computer-controlled electromagnets inside a typical drum brake assembly. When the drum rotates and passes through the magnetic field generated by the electromagnets, a Lorentz force is induced that opposes the rotation of the drum. The electromagnetic brake was compared against standards for modern vehicle braking performance to determine the feasibility of the frictionless brake’s performance. In conjunction with the electromagnetic prototype, control system and display panels were integrated into the test bench, allowing for automated control over the motor and electromagnet and automated data logging. The display panel shows the coil current, voltage, temperature along with the velocity, stopping distance, and stopping time. To ensure the coils stayed within a safe temperature, a simulation was used to determine the maximum current that could be applied before the wire would breakdown. Finally, a cost– benefit analysis was conducted to determine the economic advantages of an electromagnetic brake over a traditional friction brake. The proposed system and testing bed proved that the electromagnetic braking using eddy currents is possible and may be used to improve the existing braking systems. However, this system, as built, cannot achieve the performance required by the current braking standards. Besides the major milestones and project design, we will describe the lessons learned and assessment of this project throughout the academic year. The educational impact of such project is assessed as well, focusing on the interdisciplinary nature of the approach.