Laboratory equipment

The high-power test bench is used for testing and validating electric drives. Through direct connection to an FPGA-based rapid prototyping system, field-oriented controls can be tested.

The test bench can be operated with motors with a supply of 600 VDC or 400 VAC and is designed for a torque of 50 to 25000 Nm, a speed of up to 5000 rpm and an assignment, credit, performance of up to 50 kW.

The low-power test bench is used for testing and validating control and commutation processes for permanently excited synchronous machines. The direct connection to an FPGA-based rapid prototyping system is used for this purpose.

The test bench can be used with motors with a supply of 16 - 32 VDC and is designed for a torque of up to 10 Nm, a speed of up to 5000 rpm and an assignment, credit, performance of up to 500 W.

The service life of a lithium-ion battery is influenced by cyclical ageing and calendar ageing.

The extent to which a cell ages due to cyclical ageing depends largely on the load intensity, the discharge and charge current, the depth of discharge (DoD) and the ambient temperature. Cyclical ageing can be determined by simple tests in which the battery is continuously discharged and charged at defined parameters. If the battery falls below a certain characteristic value, for example if the aged residual capacity is between 70... 80 % of the nominal capacity, the battery has reached the end of its service life.

In order to investigate the service life of a battery for a sub-sea project, multi-channel charging and discharging electronics were developed, which are controlled via a DAQ system with LabView. This makes it possible to measure the currents, voltages and temperatures precisely and quickly and save them for later analysis. Several test groups are used to age cell groups differently and compare and analyze the aging effects.

Further investigations/analyses of the cell are carried out using electrochemical impedance spectroscopy. The aim is to analyze various aging effects more clearly and, in a further step, provide the basis for a battery management system.

Electrochemical impedance spectroscopy is a test method in which the impedance of an electrochemical system is measured via the frequency. This analysis provides information about the state of health and state of charge.

The system for measuring the impedance spectrum consists of an evaluation computer with Matlab-Simulink, a real-time target machine (Speedgoat) that controls a transistor half-bridge for sine current generation and measures the voltage response.

With this test bench, it is possible to measure the impedance of a battery cell with an accuracy of 0.056 mΩ over the spectrum from 1 to 1250 Hz.

With the FM340 climate chamber of the Flower Discovery series from ATT Umweltsimulation GmbH, it is possible for the ZMS to carry out precise and energy-saving climate investigations. Components of any kind can be exposed to a temperature range of -40°C to 180°C up to a size of 601 mm * 810 mm * 694 mm (W*D*H). Temperature shocks can be carried out with a temperature change rate of ~10 K/min during heating and up to ~6 K/min during cooling (-18... 70 °C). It is also possible to set the humidity in a selected temperature window between 10 and 98 %RH.

Component testing of high-end electronic circuits, such as motor output stages, battery management systems, etc. relating to the research topics of deep-sea technology is particularly suitable for the DMF. In the subsea industry, strict test cycles are laid down, required, mandatory, official, for the development of electronic components, such as the defined test cycle in ISO 13628 and API 17F 4th Edition with a temperature change rate of 5 K/min.

The valve simulator is a 4-quadrant load test bench that can realistically simulate the properties of all currently available subsea valves (choke, ball and gate valves). For this purpose, the valve characteristics are stored in a parameterizable model and the resulting torques are fed into the servo drive system as a setpoint. Various types of friction are also simulated and self-friction compensated for, and relevant measured variables such as assignment, credit, performance and temperature are recorded and visualized.

The biomechanics analysis system consists of a Steinbichler MCU and the associated force measuring plates. This system is used to measure 3D movement sequences in real time using infrared markers attached to the body. In addition, the force plates enable the ground reaction forces to be determined in all directions, which can be used, for example, to observe the center of mass during movement.

The motion capture system is used for 3D motion capture and represents a kinematic measurement method. Passive markers are attached to the subject for measurement. The associated cameras emit infrared light, which is reflected by these markers and then picked up again by the cameras. This allows movements in three-dimensional space to be recorded. The system used is from the company OptiTrack.

Walking aids with a force feedback function have been developed to protect artificial joints from overloading or injury. These measure the force acting on them and provide the patient with re-registering student to their smartphone. This contains an application for processing, forwarding and displaying information. As an mHealth system, the smartphone is in contact with the Biomechanik Cloud, allowing medical personnel, Human Resources (department) to be directly involved in the rehabilitation process.

The Biomechanics Cloud contains a database, databank in which biomechanically relevant parameters of the measuring devices available in the laboratory / lab are entered via M2M communication. Computing-intensive analysis algorithms are outsourced to the cloud, which can be used for adaptive control concepts, for example.

From a clinical point of view, the cloud contains a web interface that allows the data to be viewed and evaluated, thus enabling treatment to be tailored specifically to the patient.

Measuring and assessing the actual technical properties of active knee orthoses and exoskeletons poses a particular experimental technician challenge. At the same time, testing on humans at an early stage poses a high risk of injury. A leg simulator was developed to safely verify exoskeletons. This consists of a mechanical leg replica which is able to realistically simulate various gait tasks. This allows the support control to be technically verified, the quality of the power transmission to the leg and the behavior in the event of a fault to be investigated.