FH München: the piezoelectric effect

The signals of an electric eel: piezoelectric power generation on a high-tech bicycle

 

In the Department of Mechanical, Automotive and Aeronautical Engineering at the University of Applied Sciences in Munich, students are working on an innovative vision of a bicycle. In the
”Electric Eel“ project, the lightweight material carbon is combined with piezoelectronic ceramics from the field of intelligent materials. Vibrations in the frame of the bicycle produce electrical charge transfers as a result of mechanical deformation (the piezoelectric effect). The electrical energy generated in this way can be used for various applications, without additional power sources. The principle is similar to that of an electric eel, that emits current impulses through electric organs.

Two topics of investigation

1. Using a CRP (carbon fiber reinforced plastics) rear swinging fork with piezoelectric ceramics, the electrical signals generated by the uneven ground should control the dampers in the chassis frame of full suspensions.
2. In the stem, a system for monitoring the loads on the forks and the handlebars was examined. The signals of the piezoelectric modules are used to register overloads. Warning lights on the handlebars indicate, for example, when the bicycle has to be inspected.

"Against a background of safety and warranty aspects, the importance of load monitoring systems will increase drastically in many areas of machine and vehicle construction, as will optimization of maintenance cycles.

Various sensors are suitable, depending on the application. Whereas currently, investigations are carried out for mechanical engineering applications with strain gages, the benefit of the piezoelectric effect for a bicycle is primarily to avoid heavy batteries" Prof. Dr. Alexander Horoschenkoff, Project Leader at the University of Applied Sciences in Munich