Hello!
I am very new to Arduino. I am hoping to use a motor to move a lightweight object very slowly over time. The goal rate would be 0.0168-0.05mm/hr for 24-36hrs. I have tried the 28BYJ-48 stepper motor but the goal rate I'm looking for is too small for the motor's capabilities.
thanks!
if you do a web search for arduino linear actuator you will get plenty of links
Since it's particularly slow, might be better to tell what you are working with. What's the max "granularity" of you movement?
1 Like
That distance you could just use expansion vs temperature to do the job.
1 Like
I did see linear actuators - I am not sure if the wiring and set-up may be too complicated for me to do...
I don't have an exact granularity. I'm moving a thin membrane that is sensitive to harsh movements - I think probably a few degrees/second.
What is the connection to your membrane and what is holding the membrane?
I dont't know what you mean with this. I repeat, illustrate you setup little bit...
A 1000:1 gearmotor driving a traveling nut on a lead screw would be a good starting point. Look up "DIY syringe pump" for examples.
The linked motors will run on even 1V, for 10:1 speed control by voltage.
2 Likes
0.0168-0.05mm/hr for 24-36hrs.
Did you couple it to something like a M3x0.5 screw? Then it would be maybe 3600*1000/(0.0168/0.5*4096)=26157ms per step. (Assuming 4096 steps/rev, and you have backlash handled, etc...)
1 Like
the motors are connected to string that is attached to the membrane
You have to start with more information.
This is a mechanical question first of all.
Shaft diameter, maximum rate of slew, motor speed and possible gearing.
And replace the string with something that doesn’t stretch.
I played this game. This was a commercial application where we rotated a part while it transitioned for weld cladding the ID of a tube. What we did wes have the motor drive a 50:1 reduction gear which in turn drove an acme thread lead screw. Using the gear reduction we eliminate the jerky motion of the stepper. The advantage of using the stepper was we could know exactly where the weld head was inside the tube and get accurate travel and timing.
Again, this was a commercial application with a heavy part.
Ron
You like us to guess how is your setup instead of presenting it. Not the most efficient way to get suggestions...
2 Likes
Here is a simple image of what the set-up is. I would replace the string, glue, and fabric with the membrane I am trying to test later on.
The shaft diameter would depend on the motor as would the motor speed. I am not sure about rate of slew or gearing. Ideally, I would not have to add gears or pulleys.
1 Like
Few degrees per second with that setup would make 0.05mm per second, not per hour.
1 Like
From the photo, and assuming 2048 steps per shaft revolution, circular shaft diameter of 3 mm, the string on the right is pulled a distance of (3 mm)*PI/2048 = 0,0046 mm per motor step.
Command 4 steps per hour for string movement 0.018 mm/hr. No need for a second motor.
1 Like
Your picture makes me laugh!
The stepper wind up the string will also move the stepper unwinding the string just a bit, every times it pulls the string. Any vibration of your table will also move the motors. Why did you not firmly mount all the devices so only the membrane is moving?
would there be another motor that would work better for the rate that I'm looking for?
A maximum movement of about 1 mm in a full day implies astonishing precision in the rest of your project’s hardware. Can you tell us more?
1 Like