Does anyone know where I can get some rotary encoders to fit on the back of my stepper motors. If I fit them to the steppers, will that stop the motors missing positions, or are the DROs (including the encoders) just for reference and have no control over the actual motor movement.  What Im trying to do is have the motors move until they reach an actual table movement point, (as indicated by glass scales or the encoders) so that they if they miss any steps they will still complete the distance as in the program.
Have used Mach3 for 12 mths now and it works my machine great. NB: Hood, I am using my counter weighted knee system and have had no problems if I limit the rapid speed to 30" per min.(not fast, but good enough for my use)

thanks

Hi, Roger

Mach doesn't have a active feedback system, It relies on your servos or steppers to move to the correct position by the settings in motor tuning Steps Per value, There is a board that will halt mach if the steppers get out of position to far that uses encoders , But dose not correct for the error.

You may need to adjust your Acceleration and Velocity down if your losing steps and increase your Step/Dir Pulse to 5 to give your stepper controls more time to see Machs step Pulses.

What are your Steps Per values for each axis ?

Hope this Helps, Chip

Chip,

Thanks for the reply.
I havent had a lot of trouble with lost steps, but thought if I could use encoders or linear scales to control the movement it would be a failsafe, however, if it is too hard then what I have works just fine.
again thanks

rogerbsstt

Hey Roger, I think the board Chip was referring to is from Ron Rogers of Rogers Machine. Here is a link.

http://www.rogersmachine.net/encoderinterface.html

Brett

Brett,

thanks for your info,
I think for now I can live with my machine as it is,
just looking for maybe a better mousetrap, (not a solution to a real problem in my case)

again Thanks
rogerbsstt