I'm looking for a compact sensor solution to measure relative angular position for a rotating system under the following constraints:
- High-speed rotation: The system (and the sensor itself - it is not stationary) may rotate at speeds up to 1000 RPM (≈ 6000°/s), so the sensor must be capable of accurately tracking angular velocity at this rate without clipping or saturating.
- Accuracy requirement: I require an angular position estimate with a precision of roughly 1 degree.
- Electromagnetic environment: The sensor will be operating near metal components and electromagnets, so resilience to magnetic interference is necessary.
- Mounting constraint: The sensor cannot be placed at the exact center of rotation (the center of rotation is fixed) but can be mounted approximately 1 cm off-center.
- Form factor: The solution should be compact enough to fit cleanly on a PCB layout. I'm looking to avoid Hall effect sensors, optical encoders, or any mechanical angle detection methods involving external or bulky parts.
- Relative measurement: The system does not need to maintain an absolute orientation (such as magnetic north). It only needs to measure rotation relative to an arbitrary reference set at power-on.
I’m aware that many IMUs either saturate below this angular velocity or suffer from drift over time, so I'm particularly interested in suggestions for:
- Sensors or sensor combinations that can support this use case,
- Methods for minimizing or compensating for drift in high-speed relative angular position tracking,
- Techniques to account for off-axis sensor placement in angle estimation.
Edits from comment discussion
- Sensor cost must be cheap and extreme precision is not a requirement a degrees per division of around 1 degree is more than sufficient (the main concern is the device needs to sample at a sufficient rate for a rotational speed of around 1000 rpm).
- The device cannot make use of a hall effect sensor due to the aforementioned magnetic interference.
- Optical sensing methods such as optical rotary encoders also cannot be used as the device needs to be completely self-contained and can't rely on external components like an encoder disk.
- The duration of the rotation that the sensor will need to measure will varying anywhere from 1s to 45s.
Thanks in advance!
