Drives Blog

Is it possible to distinguish between analogue and digital, smooth and discrete?
Is everything quantised at some level or another, what is the smallest distance a continuous motor can move, what do we mean by what do we mean?
Do particles wave to eachother as they pass by?
Del

Try switching to decaf, Del.

SPLARF

Once you adapt to steppers and get away from gear motors you realize the precision that can be achieved.

Above a 4WD stepper motor PIG (Pipe Inspection Gage) that i developed. It measures the ID,pipe bow,ovality,length. The linear position ,length also, is accurate to .5 mm. It can inspect a pipe 480" length in 80 seconds , from the starting end and return. This would be hard to do with gear motors but once you adapt to the programming it is much more accurate.

This is rev B. we are working on rev C which will be all WY FI and battery powered (no wires).

Ron

Hey, that looks like you are having way too much fun. Will it fetch beer?
Del

Will it fetch beer?

Let me talk to my programmer.

Ron

That's some interesting work!

Once you adapt to steppers and get away from gear motors you realize the precision that can be achieved.

Of course. For something like this, steppers are ideal. However, for continuous rotary motion as in machining, steppers haven't been used due to their lower upper-range rotational velocities and the "jerk" with each step.

The "softstep" technology seems to virtually eliminate at least the stepping motion, but I wonder how the steppers handle it long-term.

Do you have a web site with more pics and documentation of this project? I would like to see more.

However, for continuous rotary motion as in machining, steppers haven't been used due to their lower upper-range rotational velocities and the "jerk" with each step.

Yeppers! However for linear motion this is a very smooth travel.

Here we are performing a traacking test(look close and you will see the laser dot). It moved with precision and no jerky motion. It is all about speed.

Do you have a web site with more pics and documentation of this project? I would like to see more.

Not at this time, we (me and the programmer) will publish after a patent search and the build of rev C.

Ron

Del has a point. The real issue is precision. Because motors involve inductance there the problem of overshoot (meaning there is a limit to the smallest motion) due to inductive effects. For most cases most modern technology is sufficient, but there are limits, I think.

Because motors involve inductance there the problem of overshoot (meaning there is a limit to the smallest motion) due to inductive effects.

Not really, there is a holding torque applied between steps. We learned this the hard way when we tried ganging 4 motors and blew out the stepper drive.

Ron