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Abstract
In this paper. the design proposed is a linear pedal drivetrain system for a bicycle. A linear
pedal drivetrain is different from a rotary system in that, the motion of the pedals is linear rather
than rotary. This system was proposed to provide an alternative to. current rotary pedal systems.
After conducting extensive background research, four design concepts were chosen to model
the system after. The concepts were: a slider-cranks, ·crank-rockers, eccentric or planetary gear
sets. and reciprocating racks and pinions.
Calculations were conducted for the gears, racks, and shaft. Then a design was constructed
in Solidworks to test the theoretical functionality. This allowed for the use of trial and error to
make important design decisions that could not be solved analytically. Once the design was fully
modeled in Solidworks, it could then be built to test full functionality.
Most of the design was made from scratch out of raw materials at the Applied Engineering
Center on the University of Southern Indiana campus. This not only gives the design more
freedom to customize components, but it also allows for the introduction of more error into the
components. Once all of the components of the design were built, they were then connected
together and mounted to the pre-existing bicycle chosen for the project.
After the build and construction of the system onto the bicycle was complete, a basic
functionality test was performed. The sector gear did not properly switch from one rack to the
other. This resulted in the design failing to propel the bicycle and rider forward for more than the
travel distance of one pedal stroke.
From the results of the basic functionality test, recommendations were made to fix the
problems of the current design. The key recommendations were to build a recumbent bicycle
frame around the linear system and change the offset between the racks on either side of a single
sector gear.