Bicycles come in many forms and shapes. New bicycles appear on the market every year with technological improvements.

One professor in the College of Engineering at the University of Nebraska-Lincoln is studying improvements on cyclists’ pedaling efficiency. He is working on improving the efficiency of power transmission of the pedaling path through the use of an optimal linkage design using symmetric four-bar, which is pictured below.

When cyclists pedal, they create pedal paths. The pedal path is the motion of the pedal when a force is applied.

Carl Nelson is a professor in the Department of Mechanical Engineering at UNL. Prior to UNL, he attended Purdue University. In his research, Nelson is working on a crank mechanism to eliminate dead center positions caused by a perpendicular force applied by the cyclist to the pedal. Due to these two dead center positions, the cyclist tires easily.

BP: Was this research conducted by yourself or with UNL
students?

Nelson: This research was an individual project that I started shortly after coming to UNL.

BP: When and how did you come up with the idea?

Nelson: I came up with the idea during 2005. I was interested in bicycles and decided to start a project to design a mechanism to increase the rider’s efficiency.

BP: When did you finish writing a paper on the bike research?

Nelson: I finished the research paper in 2006, and it came out in September of that year.

BP: What goal do you have for this project?

Nelson: The goal that I want to accomplish in this research
is to design a mechanism that will use full advantage of the force applied to the pedal. I want to eliminate dead center positions on the rider’s motion and improve the transmission ratio in the cyclist’s performance. This research is still a
prototype and in the works. Hopefully, if successful, then it would change the way cyclists perform.

A video of this prototype experiment can be seen on Nelson’s lab website:
http://robots.unl.edu/Nelson/www/index.htm

Information on Dr. Nelson’s current research projects:
http://www.engr.unl.edu/me/faculty/carl_nelson/carl_nelson.html