SingleTact performance specifications assume that the whole sensor is uniformly loaded, so the sensor should be chosen to match the force contact area. That said, useful measurements can still be performed in a number of situations. Consider the following four scenarios that show various loads resting on a SingleTact (from the top and from the side).
(a) Load slightly smaller than sensing area
(b) Load significantly smaller than sensing area
(c) Load larger than sensing area
(d) Load larger than sensing area and also resting on test surface
Distributing the load
Note, it is possible to create a fixture to evenly distribute the load over the sensor, for example (e).
1N approximately equals 100g, which approximately equals the weight of an apple. The pressure range should be chosen to closely match the anticipated pressure range. Applied loads greater than the selected full-scale range can damage the sensor.
Standard uncalibrated sensors are somewhat non-linear and hence the relationship of applied force against output does not follow a straight line and in fact is curved (Left Image). Furthermore, a standard sensor’s full-scale output is only approximately in-line with the full-scale load.
Calibrating the sensor linearizes the output and ensures that the full-scale output matches full-scale input with a maximum deviation of 2%. See example below (Right Image).
Advantages of calibration:
Disadvantages of calibration:
Calibration does not significantly affect:
When would you desire calibration?
Cases where you should consider a standard sensor
Standard Electronics - Provides analog voltage output or I²C interface. Arduino software provided for free.
USB-Electronics (Only Available with Calibrated Sensors)- Provides a turnkey plug and play simplicity and comes with the software.
The 150 mm (6 inch) extender allow you to place the SingleTacts sensor into hard to reach places.
For advice on mounting and interfacing with your SingleTact force sensor, please see our app note.
Miniature Force Sensors Leaders