Strain Gauge

Deformation sensor

• 

Libraries:
Simscape / Electrical / Sensors & Transducers

Description

The Strain Gauge block represents a sensor that generates a change in resistance as a function of strain using the following equation:

$$\frac{\Delta R}{R}=K\epsilon$$

where:

• ΔR/R is the fractional change in resistance.

• $$\epsilon$$ is the strain at port E.

• K is the Gauge factor parameter value.

Examples

Strain Gauge and Wheatstone Bridge

How to model a strain gauge and measurement amplifier. The strain gauge forms one leg of a Wheatstone bridge, which is connected to a differential amplifier. A second op-amp is then used to both amplify and apply a low-pass filter to the measurement signal. The op-amps are modeled at a system level, with the user specifying parameters such as open-loop bandwidth, gain and maximum slew rate. In this circuit, the dynamics are primarily set by the low-pass filter. The op-amp bandwidth and maximum slew rate have little impact on the step response.

• Open Model

Ports

Input

E — Strain input

physical signal

Physical signal port associated with the strain input.

Conserving

+ — Positive port

electrical

Electrical conserving port associated with the strain gauge positive port.

- — Negative port

electrical

Electrical conserving port associated with the strain gauge negative port.

Parameters

Gauge resistance — Unstressed gauge resistance

100 Ohm (default)

Unstressed gauge resistance.

Gauge factor — Gauge factor

2 (default)

The ratio K of the fractional change in resistance to the fractional change in length.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2008a