Servo torque

[rocky79]

on the hitec Hs422 the output torque at 6v is 56.93 oz/in

Is that the max torque the servo can deliver before it breaks?

I want to use this servo on a robotic arm. will it be safe to use all the 56.93 oz/in of torque or that will be the servo limit?

if that's the case what would be the usable torque ?

Thanks

[Acetronics]

Hi, Rocky

Generally that value is that the servo will hold while steady ...

NOT the value the servo will start to move its load ...

NOT the value the servo can withstand while continuous movement ...

The servo will break for much Higher values ( shocks on arm ...i.e. ), but motor or electronics can be damaged within those limits ...

The only way to Know ???

Try it or Buy industrial servomotors ... for another price.

Alain

[rocky79]

Thank you acetronics, good to hear from you.

[BushmanLA]

Yeah, generally they give you 'holding torque' which is how much torque the servo can withstand before it starts turning in the direction of of the applied force.

Remember that in order to move something you must accelerate it from rest, so if you are skimpy with the available torque you might be able to move, but it will be very slow in doing so and you will stress the heck out of the components.

My advice would be to figure out the max torque needed after including the weight of the arm itself and the length of the possible applied wight from the servo, then find a servo that can provide nearly twice that amount.

Also, speaking from experience, it helps greatly if you don't leave the arm weight sitting perpendicular to the servo bearing axis alone. Either span it between the servo horn and a free bearing, or double up and put a servo on both sides.

[Acetronics]

Thank you acetronics, good to hear from you.

Hi, Rocky

Yes , I was very occupied with numerous PIC Projects ... from my lawn tractor onboard computer to the models AZLights ...

For a "general rule" ... Consider the reasonnably usable max. torque is 2/3 of what announced by serious makes ( Futaba, Graupner/JR , Multiplex ) ...!!! ( that keeps a "decent" moving speed ... :D ).
For the copies ( sorry but Hitec IS a copy ...) take 50% ...

Here are some TRUE ( seriously measured ) data for servos ...

http://osegouin.free.fr/servo/servormances_v22_mai_2007.zip

Hope it helps

Regards
Alain

[AndyKunz]

Now that Multiplex is owned by Hitec, does that make the Multiplex products copies or does it make Hitec "serious"?!

Hitec used to be a copy (to the point of making plastic screw heads where Futaba had screws) but those days are long past.

Andy

[rocky79]

Hi, Rocky

Yes , I was very occupied with numerous PIC Projects ... from my lawn tractor onboard computer to the models AZLights ...

For a "general rule" ... Consider the reasonnably usable max. torque is 2/3 of what announced by serious makes ( Futaba, Graupner/JR , Multiplex ) ...!!! ( that keeps a "decent" moving speed ... :D ).
For the copies ( sorry but Hitec IS a copy ...) take 50% ...

Here are some TRUE ( seriously measured ) data for servos ...

http://osegouin.free.fr/servo/servormances_v22_mai_2007.zip

Hope it helps

Regards
Alain

Thanks again Alain, that link requires the knowledge of the "la langue Francaise" ;)
very interesting!

[Ron van Sommeren]

You can use http://babelfish.altavista.com for automatic translation. Far from perfect but since it's all techno-geek-speek, it will do.

MM_Calc version 2.12, written by Louis Fourdan, available in English and French. The Dualsky, Scorpion and ?? calculators are derivatives of this calculator
http://electrofly.free.fr/
-> téléchargements (icon at top of page)
-> moteurs
-> MM_Calc_v212 (zip) english version

Drive Calculator v3.31 by Helmut Schenk and Christian Person:
http://www.yahoogroups.com/group/d-calc
Direkt
www.drivecalc.de


Vriendelijke groeten ;) Ron van Sommeren
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