### Metrology Laboratory

The MTL consists of practical exercises on the topic of measurement technology. The exact dates of the individual experiments can be found in moodle. Please refer to the learning room for the current regulations regarding dates as well as passing and framework of the course. There is no exclusive learning room for the sub-experiments 7.1 and 7.2. You will find all information in the general learning room for the metrology lab.

#### IMPORTANT INFORMATION!

The personal test sheet will be offered to the student for printing at registration, this test sheet must be taken to all lab exercises!

Please take a look at the group dates before registering!

It is strongly recommended to have read the documents for the respective experiment well beforehand, otherwise participation in the experiments cannot be guaranteed. During both experiments, a test will be collected in the form of a multiple-choice test.

#### Test 7.1 Determination of spring and damper characteristics of a mountain bike

Subject of the experiment

Mountain bikes designate a class of bicycles which are characterized by their suitability for off-road riding. An essential component of such bicycles is the frequent equipment with power elements, which can improve the riding comfort as well as the performance by their springing and damping effects.

Theoretical foundations

For the investigation of moving systems with a multitude of joints and force elements, multi-body systems are suitable, which can represent complex real systems by a simplified physical model. In this way, the analysis of various static and dynamic relationships is made possible. While modeling, the real, technical system is usually represented by an interaction of rigid bodies, binding elements, and force elements.

Aim of the experiment

Using the example of a full-suspension bicycle frame, this laboratory experiment shows how specific system parameters can be calculated using static and dynamic tests. This becomes particularly comprehensible with the example of the bicycle frame, since the spring and damper characteristics of the force element installed in the bicycle frame are determined with the aid of the laws of force transmission on rigid bodies and the fundamentals of technical vibration theory, without removing it from the system.

#### Test 7.2 Balancing

Subject of the experiment

Balancing of an unbalanced rotor. Comparison of static balancing with dynamic balancing on a displacement measuring balancing machine.

Theoretical principles

Effects of uneven mass distributions on high-speed rotors. Behavior at sub- and supercritical speed: force- or displacement-measuring balancing machines. Vibration measurement using electrodynamic velocity transducers.

Aim of the experiment

Balancing of an unbalanced rotor with the aid of a displacement measuring balancing machine.

### CONTACT

Institute of Mechanism Theory, Machine Dynamics and Robotics

RWTH Aachen University

Eilfschornsteinstraße 18

52062 Aachen

Germany

Phone: +49 241 80 95546

Fax:      +49 241 80 92263

Mail:

Contact

Imprint

Disclaimer

XING