Advice needed for finding high torque 24VDC servo motor

The robotic watercraft we are building runs on a 24VDC electrical system. The servo needs to control steering and needs high torque (>100 lb-in)
especially in choppy waters. I am having trouble finding a high torque, low voltage servo. Should we just run a 75VDC servo at a lower voltage, or perform the voltage conversion? Is there a servo that meets our requirements? We would like to keep the wiring simple. I am puzzled why it is so hard to find.
Thanks ~ DD
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If you actually mean 100 in-lbs, that is 1200 foot-lbs. That is hella torque. Or do you mean oz-in.
When you say servo, do you mean R/C servo with integrated gearbox? Or do you actually mean a DC servo motor capable of this torque.
If you mean R/C and you mean 100 oz-in, try Vantec

low
it
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Incorrect math blueeyedpop. We would like 10 ft-lbs (120 in-lbs) or somewhere in that magnitude range. This would be the real industrial control type servo motor, not r/c.

system.
why
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
oops late night there, like 3:30 am late anyhow, the issue comes down to the power of the motor. Running lower volts means more amps to get the same watts. This is undesirable. I think this is why cars are migrating toward higher bus voltages as well. http://www.micromo.com/library/docs/products/GNM70130.PDF Take a look at that motor, look at the current for the 24V vs the 180V versions.
The 700 Watt version runs 24V, 330A or 180V, 41A

torque,
or
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks very much blueyedpop. Is there a brushless servo motor with a high resolution encoder with similar specs?
Thanks ~ DD

lb-in)
puzzled
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I really do not deal with brushless. They do not mesh with what I use servo motors for. ( though any AC motor is "brushless", if I am not mistaken...)

voltage,
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If you run a 75V motor at 24V you will get 1/3 the speed but the torque would be the same.

low
it
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Dan Mauch wrote:

I haven't heard of any DC motors that work that way. When you lower the voltage you lower the torque and the speed. -- D. Jay Newman http://enerd.ws/robots /
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You're talking real money here. High torque brushless servo motors, especially not at 120 or 220 volts AC, are a high-end automation application. I think you'll want to talk with an application engineer at a motor company, say like Baldor.
These things by nature have an encoder built in. You can select the resolution based on your application. Voltage can be specified when ordering.
-- Gordon
DD wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, Jul 10, 2004 at 06:13:30AM +0000, DD wrote:

I got some nice 24VDC gearhead servo motors from Herbach and Rademan that look like they meet your specs. Unfortunately, Herbach and Rademan seem to have "upgraded" their website and now all (most) of their catalog links appear to be broken so I can't point you to a URL. They were around $65 each.
I can point you to photos of my rover where they are used though:
http://www.bdmicro.com/rover/
The actual motors are:
Matsushita Electric Industrial GMX-8MC045A
The gearhead provides a 45.5:1 reduction, though I forget the actual RPM - less than 100. The built-in quadrature encoder generates 4550 pulses per phase per 1 revolution of the output shaft which provides excellent feedback of my rover's motion anyway.
-Brian
--
Brian Dean
http://www.bdmicro.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Following up to my own post to correct a mistake ...
On Tue, Jul 13, 2004 at 02:49:46AM +0000, Brian Dean wrote:

My mistake - the Herbach and Rademan site is working just fine if you go to www.herbach.com instead of www.herbachandrademan.com. The latter appears to be an older and broken version of the site. The former works fine. Here's the link to the motors:
http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=TM98MTR3114&Category_Code GEARHEAD
Or if that link is too long, here it is in tinyurl form:
http://tinyurl.com/3aepe
These are very nice motors and work great. Like I mentioned, I use them on my rover:
http://www.bdmicro.com/rover/
-Brian
--
Brian Dean
http://www.bdmicro.com/
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

  • - the site's newest thread. Posted in

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.