Rolling Resistance Testing Machine

Overview

The Supermileage Club tasked us to create a device capable of measuring rolling resistance. The device was to be essentially a reverse dyno. Their current measuring device was not capable of collecting accurate data, our device needed to be accurate and consistent.

Objectives

The Penn State Behrend Supermileage Club requested that a device be designed to measure and record the rolling resistance using a data acquisition system when testing a wide range of bicycle tires. A device was designed and analyzed to completion and turned over to the club to be fabricated. 

Approach

• After the project was established, a set of engineering requirements was defined and a project problem statement was drafted.
• The research was conducted into existing methods and devices on how to measure rolling resistance.
• Initial concepts were generated by each team member to satisfy the device’s requirements.
• The concepts were analyzed, prompting design revisions.

• An initial concept was determined, drawing benefits from each member’s design to produce an accurate and reliable measurement device.
• Components were individually analyzed for integrity using machine design and strengths of materials techniques and optimized for cost and weight using software such as GRANTA.
• A CAD model, shown bottom right, was created, and served as the basis for material selection, defining product architecture, and assigning design codes.
• FEA analysis of subassemblies using ANSYS Mechanical assured cohesion during operation.
• Laboratory testing was done to determine a proper surface to accurately represent the conditions that the bicycle tire would experience during competition, resulting in implementation of spray on truck bed liner. 

Outcomes

• Reliability of rolling resistance values specific to each tire setup.
• Allows for the Club to test tires of varying sizes and specifications, along with varying input conditions to the tire i.e., test load and speed.
• Newfound ability to make specific connections between tire selection and fuel efficiency.

• Modular design allows for adaptability as the Supermileage car evolves.