I have a customer who is using the LDC1000 in a linear sensing application. They would like to use it in a rotary application. Currently, they have a triangle to measure linear displacement, but a rotary may be more deterministic.
Is there an example of how to make the rotary wheel – as if you were going to measure motor movement?
Hi John,
There a many different types of rotation applications. For example, if you need to measure a partial rotation (for example, only 270 degrees of rotation), then a single coil can be used with a target rotated around a pivot point. Note that it is important to control the Z height.
For a full rotation, 2 or more coils are needed. A good implementation using 2 coils with 90 degrees apart on a sensor board, as shown below:
We then have a rotating target for the sensor to detect. A good target shape (where the orange is copper) is:
The target would be attached to the rotating component while the sensor board would be fixed. A side view would be:
It is important to maintain a fixed separation. To determine the angle, measure the response of the two coils and use the Arctangent function to determine the angle.
Regards,
ChrisO
