Semi-Automated crash test sequencing with Perception CSI
Testing and certification of car safety belts and child restraint systems.
The customer - a Dutch test house doing research and development of automotive systems and components - bought a Liberty DAQ device for undertaking car safety belt tests.
The problem, however, was that the operator had to complete far too much manual preparation before and after a single test. This was time consuming, erroneous and inaccurate. It was also too demanding for the operators.
Another problem was the interaction with an existing administrative program and with the controlling software of the test circuit.
Lastly, in order to analyse data according to the SAE J211 standard relevant in this application, a special low pass filter was needed.
The solution: The general solution was based on a Liberty with strain gage input modules. Most of the analysis and display requirements could be solved with standard Perception.
The missing link: Standard software cannot perform an automated measurement as proposed by the customer. No standards available for communicating with other (administrative) systems. Also, the crash test
standard did require a special signal filter which was not available in Perception.
The solution was found in building a CSI application where the whole measurement cycle was automated and where interaction was established between Perception and the administrative program. The communication with the test circuit software has also been implemented.
The CSI solution
With CSI it is possible to program an automated measurement cycle according customer specifications. In this case a lot of pre-testing has to be done because we are dealing with destructive tests. Some of the pre-test activities are:
- Liberty Battery test and CF space check
- Communication with external administrative software
- Excitation test of bridges
- Check if sensor calibrations date is valid
- Adjust offsets of bridges
- Shunt check
After Liberty has been armed, the CSI program sets a PC hardware I/O port, this status is read by an external system which controls the test circuit.
After the measurement has been taken the bridge sensors will be checked again to ensure data integrity. Calculations will be done and a test report will be printed. A special filter was added to the formula database.
