Sourcing a fast enough encoder

Hi Guys,
I’m doing a Pick&Place machine conversion from stepper motors (really slow) to BLDCs with oDrive. I’ve got some good 8 pole pair inrunner motors but I’m having some problems sourcing a proper encoder. With a P&P machine you want high speed, but also high resolution. I’ve already got one of these at home:

Nice and quite expensive device, but it seems it’s not fast enough. The max frequency of the encoder output signals (HTL inverted) is 200kHz. So for a resolution of 4096 PPR, the maximum RPM is:

200.000 * 60 / 4096 = 2929

Which is a bit low, since the motor can do 6000 RPM. At this point I don’t quite yet know if I’ll be able to run the machine at 3000RPM, but I don’t want the encoder to be the limiting factor. I’ve looked around for other 58mm sized (or similar) encoders, and they all seem to be limited to the 200kHz signal frequency. Has anyone been able to source something faster (potentially cheaper as well) ?

Thanks for any tips,

Is there no way you can use the AMT102v? It is the recommended encoder for odrives, and goes up to 15.000rpm at a resolution of 2048 (512ppr x 4 quadrature).

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That encoder is a quadrature model, so it actually emits two 1024-pulse-per-revolution signals slightly out of phase. Because of this phase difference, there are four possible combinations of phase A and B per pulse, so the controller can distinguish 4096 total positions with the two 1024-pulse signals. So the bandwidth is only a quarter of your calculations, and maybe you should give those encoders a shot and see if they work.

The maximum resolution of the AMT encoder is 2048 PPR which is 8192 increments per revolution. The speed limit is about 6k rpm at that resolution. There is some hysteresis but not like an optical encoder so you have to tune your positioning in accord with the noise level.