Contact Switches

An assembly of four Force Sensing Resistor Sensors (FSRs) each on 1.5 meters of cable which are readily connected to the DataLOG, DataLINK or K800 Amplifier via one connector for use as switches to indicate contact e.g. heel and toe strike or palmer contact.

The sensors are thin and robust and are usually placed inside the subject's shoe or glove for convenience.

The FS4 Contact Switch Assembly connects to one of the digital input ports of the DataLOG, DataLINK or K800 Amplifier. The programmable active edge of the input may be defined within the Digital Set up window of the Analysis Software.

The digital traces of the four contact switches may be displayed in one of two formats:

  • As separate traces that indicate logic 0 or logic 1
  • As trace pairs where two digital inputs are combined to produce a number in the range 0 to 3. In this mode, the weighting of the digital inputs may be changed; selecting 1/2 for example, results in trace 'A' contributing 0 or 1 to the final display and trace 'B' contributing 0 or 2

This pairing of the digital inputs would be used, for example, in Gait Analysis. With two contact switches placed on each foot – contact on/off will be registered. This synchronizes display of the gait pattern ( heel strike-full foot-heel off-toe off ) with other physiological parameters such as joint angles or EMG.