Laser Extensometer - Sensor Version - Fiedler Optoelektronik GmbH

Models

Sensor System

Multi Point System

Working Principle

General

Schematic of Sensor Setup

The 'Sensor' is typically used for standard applications when replacing another strain sensor at the testing equipment. The 'sensor' is the simple 'out of the box' version of our laser extensometers. Its main purpose is to output strain as an analogue voltage thus making it very easy to integrate into existing testing equipment. It consists of the laser extensometer itself and the data processing unit.

Beside the output as an analog voltage, the data is available digitally through an RS232 interface. The RS232 can be used to control the operation of the laser extensometer in detail. For a simple start/stop control, TTL input lines are available.

Based on its flexible interfaces the 'sensor' can easily be integrated in any tensile testor environment. Integrations into systems of well known manufacturers are readily available.

Interfaces

Analog Output	Output of strain +/- 10 V (scaling is user defined) second channel for special data output available
RS 232	Controlling the system, read current values, check status conditions, control analog output
TTL	Start and stop the system
GPIB (optional)	Controlling the system, read current values, check status conditions, control analog output
Status Monitor (optional)	Display information about current status of the laser extensometer (working conditions, current values, status information)

For a very simple operation of the laser extensometer, two TTL lines are used to control the system: START and STOP. When START is signalled, the laser extensometer starts the processing and determines the reference length automatically. The system keeps running until STOP is signalled - then the laser extensometer is stopped and reset for another measurement.

Advantages

The 'sensor' provides the same advantages as our more powerful solutions:

Contact free	The laser extensometer is contact free and therefore does not influence the specimen.
Drift free	The laser extensometer is drift free already in its most simple configurations. Variations which could cause a drift are monitored online and the calculations are adjusted appropriately thus eliminating any drift.
Self referencing	The laser extensometer determines the reference length automatically.
Simple interfaces	The laser extensometer provides a variety of interfaces. TTL lines, analog output and RS232 are standard features. Optionally GPIB is available. Already with the simple TTL-lines and analog output it can easily be used in most tensile testing environments.