Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Need to build reverse and forward motor with custom speed

Need to build reverse and forward motor with custom speed

Need to build reverse and forward motor with custom speed

I need a motor that can rotate forward and backward with speed I want. Basically, I want to pull a rope (with motor) about 6 inch in 1.6 seconds and release same about 6 inches in 0.8 seconds.
Sorry, if requirements sounds weird but this is for a project I am trying to make for daughter's therapy.

I believe I would need a motor, some timer chip and ropes. Can you please guide me where should i buy and what should i buy for this project.


RE: Need to build reverse and forward motor with custom speed

How hard does it have to pull? Why does it have to rotate?

I would look at a linear actuator, a motor driver, and an Arduino to control the driver. You'll also need a suitable power supply and some way to mount motor.

RE: Need to build reverse and forward motor with custom speed

OR, you could use a crank with a 3 inch radius, and a motor that can run at two speeds, but it doesn't need to reverse. It's possible that the load applied could slow the motor down a bit on the 'up' stroke, and the motor will naturally go faster on the 'down' stroke if the load is constant in direction and/or is removed for that part of the cycle. So, a motor that nominally rotates a full turn in 3.2 seconds, or 18.75 rpm. Motors don't go that slow easily, so a small gearmotor is indicated, with a small motor, size depending on load, which is so far unspecified.

The rope can have an eye and a thimble over the crank journal, and if the rope is long enough, you don't need a slider, just a few guides.

You have to be _really_ careful if this device contacts the patient.
You probably need a local engineer with some specific experience to guide you.

Mike Halloran
Pembroke Pines, FL, USA

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close