The load that is applied to a pushrod (or any other
component) can be measured by mounting a strain gauge to
the pushrod.
A strain gauge is a resistor made from foil that is bonded
to a dielectric backing (insulator). When the strain gauge
is bonded to a material and the material is stretched or
compressed it will change in resistance. This change in
resistance can be used to measure the amount of force that
causes the material to stretch or compress. This is done
by converting the resistance change into a voltage and is
achieved by connecting four strain gauges into what is
known as a wheatstone bridge.
When a number of strain gauges are configured into a
wheatstone bridge, they can be used for precise
measurement. When a voltage is applied to a wheatstone
bridge (typically 5 or 10 volts) it will create an output,
usually in milli Volts (mV). If a force is applied to the
material that the wheatstone bridge is bonded to (strain
gauges), it will compress or stretch. This will produce a
change in the wheatstone bridge output expressed as mV/V
(mV output from the bridge per unit Voltage input). This
mV/V output is then calibrated by applying a known force
(kilograms, pounds or Newton’s) and the part can then be
used as a sensor.
A strain gauge can be mounted onto almost any material
sample, the most typical being steel, aluminium, titanium
or carbon fibre. This allows the forces within components
on cars to be measured, i.e. suspension components. The
most accurate data can be achieved if the suspension
component is designed with strain gauging in mind.
For more information download a specification sheet or contact us. Alternatively phone +44 (0) 1379 646212 to speak to a specialist right away.