I have a need for a "true absolute" encoder with a relatively tough specification. I have a design and hand-made working prototypes (proven) for a 6 bit version and I now need to have the whole design finished professionally and made into a commercial unit, hopefully with a couple of upgrades on the way.
The current design uses Avago reflective optical sensors (6 in the prototype, giving 6 bit resolution, but prefer to go higher, if feasible) using a single track grey code wheel. The specification:
- 100 degC ambient operation
- 7mm thick, or less
- Through hole mounting (e.g. to fit on 8mm gearbox shaft)
- True absolute (reading at power on without movement)
- 6 bit resolution or higher
- Ideally incorporates a high resolution (365 line) relative track for interpolation
- 23mm outer diameter of housing
- Serial digital output (e.g. CAN bus, 485) of decoded angle
- Low power consumption (battery operation)
I have all the code tracks for 7, 8, 9 bits, etc. and conversion algorithms. Can provide Solidworks drawings, PCB drawings, etc., of current design. Attached zip file shows pdfs of main parts of current thoughts on a design and a photo of the hand built working prototype.
NB: Please only apply if you have experience in the area of sensor development! Deliverable must be a working and tested product to agreed specification. Alternative methods to the suggested design that achieves the specification will be welcomed. (For example, due to the tight space constraints, fibre optics could be used to get a signal away from the restricted space and provide more room for the sensor processing electronics).