Abstract
KEYWORDS:
bicycle components, test bench, software, carbon fibre
ABSTRACT:
In the past years, at the University of Applied Sciences Konstanz, we have been building a bicycle laboratory. The latest addition to our test equipment is a newly developed test bench for saddle- and handlebars, developed together with Brunn Autoland. Although the test bench has been planed for quite some time, its development was accelerated once a potential customer showed interest in our project. Our partner, who has become in the meantime also our first client, produces low-weight carbon fibber bicycle components. The intention is to prove if the newly developed carbon fibre components can meet the DIN standards.
The test bench has a rigid frame that consists of high-strength aluminium beams. The static and dynamic load needed to test the components is generated by means of two pneumatic cylinders. A Siemens S5-95U SPS unit performs the control. In the memory of the control unit can be loaded different testing programmes according to the DIN or DH standards but also customized tests according to the client#s wishes. Connected to this unit there is another micro-controller, which adjusts the air pressure that is supplied to the cylinders by means of two proportional valves. This controller displays the momentary force and the cycle counter as well.
The SPS software is written in Step5 and the Motorola controller is programmed in a basic-dialect compiled to a machine code.
The paper presents the construction of the test bench, the testing procedure and results.