Encoder Emulation via Digital outputs?

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ScheurerF
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Joined: 23 Aug 2017, 20:19
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Encoder Emulation via Digital outputs?

Post by ScheurerF »

Hello,
we are not using RevPI, yet.
I see that A/B-encoder input is possible.

Is it also possible to create an A/B-encoder output signal by the DIgital-Outputs?
What Software support is needed?
Can it be done as application on the RevPi?

Best Regards and thank you in advance
Fritz
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volker
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Joined: 09 Nov 2016, 15:41
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Re: Encoder Emulation via Digital outputs?

Post by volker »

Hi Fritz,
sorry but we only support PWM output by the DIO / Do Firmware. You would need to simulate encoder output by RevPi Core software. But due to a large PiBridge cycle time of >10 ms (depending on the amount and type of modules and the configuration of the modules) your resolution is limited. You would need a timer of let's say at least 15 ms (you need to find out the time when you have designed your complete PiBridge configuration) times 4 phases of the A/B resulting in a 60 ms encoder rate. So if something around 15 Hz is good enough for your A/B signal then you could give it a try.
But how about telling us what you are aiming to? Do you have a controller with A/B input and you want to simulate an encoder with the RevPi? What kind of physical signal will end up as A/B signal? sounds really interesting but also a little uncommon - but that's what revolution is like ;-)
Unser RevPi Motto: Don't just claim it - make it!
ScheurerF
Posts: 3
Joined: 23 Aug 2017, 20:19
Answers: 0

Re: Encoder Emulation via Digital outputs?

Post by ScheurerF »

Thank you!
I see that it will not work.

A more detailed specification:
[Encoder emulation module for a Sercos IO similar to the emulation card available on the Servo-Drive. The same module or a different encoder module could bring encoder signals into the control without the need for a servo drive, similar to the function of the Encoder card on a Servo Drive. The output should include a TTL, square-wave, 5VDC output at a minimum. Interpolation is needed on the output signal. ]
If anyone is aware of a solution that can be attached to a Sercos network, then let me know.
Best regards
Fritz
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volker
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Joined: 09 Nov 2016, 15:41
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Re: Encoder Emulation via Digital outputs?

Post by volker »

Hi Fritz,
don't take this suggestion too serious, it just came up in my mind and I needed to smile :-)
Why maken a big deal out of this task? simply take any cheap encoder an dmount it to a small 24 V DC motor. Attach this motor to our PWM output and the encoder output to your PLC. Simply control the A/B frequency by running the motor... okay if you want to give a specific number of A/B pulses then this "retro emulator" can't help. You could at least use 10 V pulses and connect them to your PLC AND our A/B input (up to 2 kHz) to get the count and compare it to your PLC's count in order to tet the input...
I know... You will hate the motor's sound and the laughing of your collleagues. BUT IT'S FUN!!!
Unser RevPi Motto: Don't just claim it - make it!
ScheurerF
Posts: 3
Joined: 23 Aug 2017, 20:19
Answers: 0

Re: Encoder Emulation via Digital outputs?

Post by ScheurerF »

Thank you :D !
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