Pages: [1]   Go Down
Author Topic: Heavy Duty motors for motion platform  (Read 1236 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Newbie
*
Karma: 0
Posts: 4
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

We are planning to build a 2DOF motion platform to connect with unity3D (example https://www.youtube.com/watch?v=BT_Xnu-gAJU). I already got unity working with the small servo's. But when i search on google or youtube, i get al kinds of 2dof motion platform but non of them explain the type of motors/servo's the use. So what i'm looking for is someone who knows what kind of motor/servo i should use, that works with arduino. And is strong enough for a motionplatform (youtube video) with a load of max 150KG. I'm really looking for a fast and silent motor/servo.
« Last Edit: September 26, 2013, 02:23:44 am by mkanon » Logged

Phoenix, Arizona USA
Offline Offline
Faraday Member
**
Karma: 40
Posts: 5575
Where's the beer?
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

I'm really looking for a fast and silent motor/servo.

You really have at least four variables working against each other here:

1. Speed
2. Noise
3. Power
4. Cost

Fast, silent, able to move a lot of weight ===> $$$$$

...and that's just for the actuator - the cost of the power supply is also going to be relatively high as well.

That said - have you looked into Firgelli Automation products - specifically their linear actuator line?

For instance - here's an actuator that can move 100 lbs (approx 45 kg) fairly quickly:

http://www.firgelliauto.com/product_info.php?cPath=114&products_id=246

$169.00+ USD isn't cheap - and that is only 1/3 of what you need for your spec; they sell ones that can move the weight you're asking, but they are more expensive - I also didn't see any that were fast. Typically, with electric-motor linear actuators, speed trades off with the amount of weight it can move. You'll also need to shop carefully to find one that has an integrated potentiometer for position feedback (plus the costs of either a servo interface, or building one yourself - for each actuator).

A different option (but still fairly expensive - unless you get lucky; I suggest checking ham-fests and the like) would be to use two electric power-chair gear-motors (such as are used for differential-steered chairs). Mounting a lever on the end of the shaft (that, or some other rotary-to-linear conversion mechanism) in place of the wheel will probably be tricky. The motors typically run on 24 VDC, and require extremely hefty h-bridge controllers to handle the load - but they are very quiet, fairly fast, and can move the weight you are specifying needed. Depending on where/how you find the motors, expect to pay anywhere from $100.00 to $200.00 for the pair of motors. Or - if you are really lucky, sometimes you can find them for much cheaper - search for a whole chair online @ craigslist; also shop at thrift stores and similar (I have found full chairs very cheaply before at Goodwill; once, it was half-off Saturday, and I could have bought a complete chair for $20.00! The only reason I didn't was because of how much the chair weighed). Note that if you go this route, you'll have to come up with your own feedback system to implement a servo feedback loop (PID or otherwise).

Another option (not really recommended, though - and likely to be very expensive for all of the parts) - would be to use electro-hydraulic (and stick the pumps into a sound-deadening box, another room, outside, etc). The hydraulics will run you quite a bit, and hydraulic fluid leaks can and will be a problem indoors; again, you'll need extra parts for the servo loop...
Logged

I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.

0
Offline Offline
Tesla Member
***
Karma: 143
Posts: 9586
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Your next step up you might try a windshield wiper motor modified to be a giant servo.

https://www.youtube.com/results?search_query=wiper+servo&oq=wiper&gs_l=youtube.1.1.35i39l2j0l8.101069.103805.0.109299.5.5.0.0.0.0.157.531.3j2.5.0...0.0...1ac.1.11.youtube.PCWDRxMFZC4
Logged

Consider the daffodil. And while you're doing that, I'll be over here, looking through your stuff.   smiley-cool

Offline Offline
Faraday Member
**
Karma: 62
Posts: 3013
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

To pull a little wheeled platform, with 150 kg mass on it,  sideways on a decent floor,  does not usually require something
that will actually pick up 150 kg.

So you need to review carefully what your actual requirement is,   and what the actually capability of the device you
are planning to use, is.
Logged

Offline Offline
Faraday Member
**
Karma: 62
Posts: 3013
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Disregard that.  I didn't watch the video.  My idea of 2DOF is different to yours.
Logged

0
Offline Offline
Shannon Member
****
Karma: 206
Posts: 12169
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

We are planning to build a 2DOF motion platform to connect with unity3D (example https://www.youtube.com/watch?v=BT_Xnu-gAJU). I already got unity working with the small servo's. But when i search on google or youtube, i get al kinds of 2dof motion platform but non of them explain the type of motors/servo's the use. So what i'm looking for is someone who knows what kind of motor/servo i should use, that works with arduino. And is strong enough for a motionplatform (youtube video) with a load of max 150KG. I'm really looking for a fast and silent motor/servo.

You have to do the maths I'm afraid - its simple mechanics for the most part, you
need to find out the maximum required torque and speed for the motor (you have the
freedom to choose gear ratios to trade one for the other.)  You also need to choose the
linkage geometry (for instance the one in the video, or linear actuators).

Also "150kg load" isn't enough - you need to know how far off-axis the load can be to
calculate torque.

Given a maximum required torque and speed you can start looking for motors (but
have a healthy margin on the torque, you don't want a motor to be struggling).
Logged

[ I won't respond to messages, use the forum please ]

Pages: [1]   Go Up
Jump to: