High speed linear actuator required
High speed linear actuator required
(OP)
Hi all,
I'm basically after a linear actuator on steroids.
Here are the required specs:
0-80mm stroke, 1040N Force, 0-10m/s speed.
I have found a few products that would almost be suitable: http://www.tacrockford.com/product/machine-compone...
But they do no meet the requirements of opening at 10m/s...
Background of use of product:
I work for an electrical switchgear company. We are basically looking at developing some new linear switches, and require a mechanism that can be used to test some new concepts.
I've been searching and contacting companies for the last two weeks have pretty much just gone around in circles.
Do you have any advice on how I can approach this problem?
Thank you in advance.
I'm basically after a linear actuator on steroids.
Here are the required specs:
0-80mm stroke, 1040N Force, 0-10m/s speed.
I have found a few products that would almost be suitable: http://www.tacrockford.com/product/machine-compone...
But they do no meet the requirements of opening at 10m/s...
Background of use of product:
I work for an electrical switchgear company. We are basically looking at developing some new linear switches, and require a mechanism that can be used to test some new concepts.
I've been searching and contacting companies for the last two weeks have pretty much just gone around in circles.
Do you have any advice on how I can approach this problem?
Thank you in advance.





RE: High speed linear actuator required
You say 0-10 m/s, then suggest that you need a minimum speed of 10 m/s.
You say 0-80 mm stroke. Do you also mean a minimum of 80 mm stroke?
The context suggests that you do.
I.e., you want to propel some mechanical doohickey by 80mm in 8ms or less.
If it only has to work once, explosives become a possibility.
If repeated operations are a requirement, then you need to look at mechanisms that store energy at some slow rate and release it at a much faster rate.
I think air rifles would be a good place to start.
Mike Halloran
Pembroke Pines, FL, USA
RE: High speed linear actuator required
It will need to be used mulitiple times and is not a once off solution.
10 m/s is the opening speed for an 80mm distance.
If it is a 70 mm distance, the opening speed required is : 8.75 m/s.
If it is 60 mm; opening speed is: 7.5 m/s
Basically it needs to complete the opening motion for a specified travel length varying between 2-80mm, within 8milliseconds.
As the gap reduces - the required opening speed decreases.
In the worst case scenario: it needs to open 80mm in 8 milliseconds .. which means the mechanism needs to travel at 10m/s.
RE: High speed linear actuator required
RE: High speed linear actuator required
Sorry if that sounds negative, it isn't intended to be, I'm just trying to understand what your objectives are in this exercise.
RE: High speed linear actuator required
RE: High speed linear actuator required
you just need 40,000# (140,000N) thrust for the 221,500 in/sec/sec (5,624m/sec/sec) accel & decel rate to make that 8msec trapazoidal move of 80mm. oh, ya, your top speed is 590.5 in/sec (15m/sec).
but good news! at least you won't need hearing protection against a sonic boom - speed of sound is 13,397 in/sec!
RE: High speed linear actuator required
RE: High speed linear actuator required
Just one last spec: at the peak of the 2msec accel ramp, putting out this force and speed, will take approximately 2,110,000 watts (given a typical linear motor).
that would be 220,000 vac 3ph @ 294 amps assuming the linear motor can handle these values.
(/fun_off)
You won't find a linear motor that can do what you want.
RE: High speed linear actuator required
RE: High speed linear actuator required
If you're looking for an actuator with this level of Force, Speed and Stroke and you need a range, you might want to take a look at LinMot. They are an excellent servo controlled, linear actuator.
Regards,
Rich.....
Richard Nornhold, PE
http://www.energizer.com
RE: High speed linear actuator required
Right now while we develop the interrupting device we need to develop a mechanism to do the testing for various configurations. With the stored energy system, there is not much room for varying the mechanisms specifications once it has been made.
Hahaha - "won't need hearing protection against a sonic boom"
- thank you all for the input. Honestly, thank you so much for the suggestions.
I'm glad I put this question up. It definitely helped me clear up that it's not a very simple solution. I put it up, incase I missed something very obvious. I've been looking into servo controlled linear actuators in more detail. I think the concept of rifles/bullets will require too much work to from an OH&S(occupational health and safety) perspective.
I may have to adjust my requirements to see if I can still 'test' the new products we plan to develop.. anyway, I'll hopefully be able to adjust my requirements once I bring this up with the switchgear engineers.
Thanks guys.
Right now this is what I'm leaning more towards: A reciprocating engine with a clutch type mechanism. The motor will be able to be started up and will be spinning the output shaft at the required speeds. As soon as I need it to engage and open the mechanism; It's a matter of 'dumping' the clutch, and hopefully with that the acceleration will be achievable.
RE: High speed linear actuator required
There are some very knowledgeable guys in forum1083: Fluid Power engineering who could tell you more than I can about where the limits are.
RE: High speed linear actuator required
A free motion sizing program such as Motioneering by Kollmorgen can help you try different types of actuators such as linear motors, rotating wheels, etc:
http://www.kollmorgen.com/en-us/service-and-suppor...
RE: High speed linear actuator required
If you are considering clutches, look at the flywheels and air operated clutches used to drive alligator shears such as are used to cut re-bar. If you go that route, look for a high slip motor to drive it.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: High speed linear actuator required
I will look into the Motioneering Program today.
In regards to designing the hydraulic system... I really don't want to have to go into the specifics too much myself. Ideally I would like a company with the experience in making them to specify what I need for my requirements.
For Example, it's like buying a car: I want a car that does 0-60mph in under 6 seconds. I am not going to learn everything about forced induction or v8's (etc)... I just want a manufacturer to tell me; "here, our VW Golf R meets your requirements, it uses a turbo charger on 2.0L motor".
Does that sort of make sense? I want to have a general idea of how the mechanics work... but not in the full detail that would require me to design the entire mechanism myself.
RE: High speed linear actuator required
Mike Halloran
Pembroke Pines, FL, USA
RE: High speed linear actuator required
RE: High speed linear actuator required
Mike Halloran
Pembroke Pines, FL, USA
RE: High speed linear actuator required
I can get a high speed electric cylinder/cylcindrical linear motor... (http://www.tacrockford.com/product/machine-compone...)
couple this with a effective lever type mechanism, and get the required opening speeds!
So if this thing can open at a maximum of 1 m/s... then I couple it with a lever that moves 10 times the distance for every 1m this mechanism moves(http://images.tutorvista.com/cms/images/38/lever.P...)... and then Boom! I have a device opening at 10m/s!
Only issue is the applied force, but my force requirements are quite low in comparison to what can be outputted in these devices!
RE: High speed linear actuator required
Before you get all lathered up about electromechanical stuff, review the kinetics that Mike Kilroy outlined above.
Don't forget the time that it will take to build current and force against the inductance of the forcing device. You probably lose at least a millisecond there, but you need to work it out for yourself.
Or rent a systems guy.
Mike Halloran
Pembroke Pines, FL, USA
RE: High speed linear actuator required
The same technique is used for glass testing. A large weight lifted on a cable. The weight is dropped from an exact height and swings down in an arc to hit the glass. The weight, cable length, and height completely specifies the speed and energy at impact. You could do the same having the hammer strike a rod to impart your linear motion.
Keith Cress
kcress - http://www.flaminsystems.com
RE: High speed linear actuator required
Having said that, I HAVE turned off breakers and switches, and it never seemed to me I had to do it in 8 msec.
So, is it possible this may NOT be a requirement after all? Please tell us why this is required for the test; mind you, I am not saying is not required, but it is hard to understand why it would be important.
Keith's idea of hitting a nail with a hammer device sounds intriguing too.... reminds me of the hydraulic lifters in a car pushing valve up and down (sure it is on nice smooth cam but maybe something in the idea would help too..)
RE: High speed linear actuator required
There's a world of difference between the speed you operate the handle and the speed at which the internal mechanism actually travels. Most breakers use stored energy in springs to provide the high speed operation, as distinct from 'dependent manual operation' types in which the contact movement is governed by the skill of the user. DMO switches have a long history of disruptive failures, often resulting in an arcing fault. DMO gear is virtually extinct these days, and that is a wholly positive step.
RE: High speed linear actuator required
RE: High speed linear actuator required
Mike - The critical component of most switchgear is the interrupting device. Some switchgear manufacturers just buy this part off the shelf. I need to test these different off the shelf solutions, and I need a device that can accommodate for varying lengths and open and close the switch to it's required specifications.
I think the simplest way to explain it is by using an analogy of a car. Right now, I want to test a 4 cylinder, a v6 and a v8 engine. I haven't decided what's best for my car yet. I need a chassis that can accommodate for all of these. Once, I have actually chosen my engine... then i will design the specific body for it.
" why anyone would need to test the stored energy motion part separate from the spring-energy-release part." ... Most of these mechanisms are very specific, and work for one specific case. Currently I need to evaluate a whole series of devices. This is a little CAD file I made earlier to show the internals of the switch.
8.333m/s - This is the time it takes for 1/2 a 60hz cycle.
RE: High speed linear actuator required
RE: High speed linear actuator required