Lubricant performance in bicycle roller chains. (View Article)
Characterizes wax and wax-emulsion lubricants on this rig over repeated characterization runs and usage intervals.
Introduction Top
For the central project in my graduate research at Purdue University, I led the design and development of a cycling test rig. Initiated in 2020 under the guidance of my PI, Dr. Mansson, this project addresses the growing popularity of virtual cycling and the critical need for regulated power measurement in cycling smart trainers.
The rig enables rigorous evaluation of smart trainer accuracy, a necessity for fair competition in virtual cycling. I also extended this project to use for studies in cycling chain lubrication, by using the testing rig to perform precise assessment of cycling drivetrain lubricant efficiency over time.
My contributions included overseeing the entire lifecycle of the project, from initial conception and design to assembly, electrical integration, and software development. The testing rig has been instrumental in collaborative testing with the International Cycling Union (UCI) to test and evaluate smart trainers for world competition homologation.
Testing Rig Design and Development Top
I spearheaded the design and assembly of the testing rig, incorporating feedback from fellow researchers such as Justin Miller and Diana Heflin. Key components (Figure 3) include: (A) AC motor, (B) gear reducer, (C) torque transducer, (D) rotary encoder, (E) smart trainer/drivetrain, (F) electrical box, and (G) back side view.
The control and analysis software, crucial for data acquisition, was developed in Python using PyQt5. I was primarily responsible for this software, with later support from Patrick Cavanaugh. The user interface is shown in Fig. 4.
Smart Trainer Testing Configuration Top
In this configuration, the drive system inputs power into the attached smart trainer. The control program reads the power reported from the trainer and the power from our testing system. By knowing the difference, we calculate accuracy. This setup helps "homologate" trainers to ensure all models used in high-level virtual cycling read the same power values.
Cycling Drivetrain Testing Configuration Top
The smart trainer was replaced with a standard cassette and derailleur (Fig. 6, F), along with a second torque transducer (Fig. 6, E) and a controllable electromagnetic brake (Fig. 6, D). This setup allows precise measurement of power input to the drivetrain and power output after transmission, enabling calculation of efficiency.
Within the drivetrain, we focused on the effects of chain lubrication. We test chains from 200-800 W and 60-120 RPM, running the chain for an hour to see how the lubricant performance degrades over time.
Related Publications & Media Top
The following highlight the cycling test rig and its applications.
Peer-Reviewed Publications & Patents
The following publications and patents showcase contributions from this project:
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A high precision in-situ chain wear measurement tool. (View Article)
Precision chain-wear checker developed alongside drivetrain testing; chains for validation were worn on this rig.
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A novel model for bicycle drivetrain efficiency. (View Article)
DCM model and test data from this rig for predicting efficiency across torque and cadence.
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Apparatus and methodology for smart trainer homologation analysis. (View Article)
I led the development of the cycling testing rig described in this paper, which is used for assessing cycling home smart trainers.
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Patent: Systems and methods for testing a bicycle training apparatus. (View Patent)
I served as the main design engineer on the design and manufacturing of the cycling testing rig.
Media Highlights
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Helping virtual cycling belong on the global stage Purdue University (View Article)
This article details our work at Purdue's Ray Ewry Sports Engineering Center in developing a homologation system for virtual cycling.