×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

HELP......Linear actuator

HELP......Linear actuator

HELP......Linear actuator

(OP)
I've been tasked with trying to find a linear actuator of some kind to run a piston test rig, the rig must be capable of around 20-30N force with a stroke of up to 90mm. I've been looking looking at the speeds of those available and most are coming up short to my requirement which ideally be 20m/s !!!, I would have thought these actuation speeds are unatainable, however I'm no expert hence my thread, anyone any recommendations or assistance?  Max speeds available on the market might give me some ideas as to which form of actuator I need to be looking at.
 

RE: HELP......Linear actuator

What does your expected motion profile look like, i.e., accel-decel rates, jerk, etc.

So far the technology at the link below has the fastest velocity (11 m/sec) for a mechanical system that I have found.

http://www.nasatech.com/motion/features/feat2_0210.html

Maybe an over-sized hydraulic cylinder with a servo/proportional valve in closed loop.

Obviously, the motion profile is significant as mechanical systems will "jerk" themselves apart at inappropriate accel-decel rates.

RE: HELP......Linear actuator

Do you need a 20m/s (about 44 MPH) actuating speed or a 20m/s2 acceleration rate? At 20m/s you are going to get to the end of your 90mm stroke in 4.5ms (give or take a few ms based on the accel rate). At that speed whatever you have that will stop the travel at the end of your 4" stroke will be getting hammered!  


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln  
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies  

RE: HELP......Linear actuator

I have never seen a linear actuator run that fast.  I am assuming that you need to start from zero speed and then stop the rig at the end of the 90mm.  That is pretty darn snappy...

I would look at pneumatic cylinders with a rubber/polymer bump stop on each end.  If it needs to decelerate itself you can bleed air into the other side of the piston as an air brake.
 

Joel Olson

RE: HELP......Linear actuator

Pneumatics won't last long.

Use a motor and put on an eccentric.

 

Charlie
www.facsco.com

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! Already a Member? Login



News


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