I am currently working an a robot arm and have encountered an unexpected dilemma. I am using a HS645 servo for the base rotate, but it only has 180° of range and I’d like to have at least 270°. Is there any way to expand the range of this servo?
I can’t remember where but I’ve seen something about adding a resistor to the pot in order to alter the voltage so the servo thinks it hasn’t moved as far, is there any truth to that?
That doesn’t sound right. what ms range pulses are you giving it?
you can gear it, and move the pot to the output shaft.
Alan KM6VV
I’m new to this and not exactly sure what you mean, but the range is listed online as 180° and turning it by hand only rotates about that much
So my only option is to physically gear the pot separately from the horn? And I’m guessing you don’t know of any directions or what not for this?
that’s about it for a 645, some others like a digital 5645 can get a little more range, but not 270, as I recall.
the gear and external shaft is how one does a full pan for a camera.
Alan KM6VV
Sail winch servos usually can rotate several turns, but the degree resolution may be poor. Servocity has gear sets and such for servos.
servocity.com/html/gears___sprockets.html
servocity.com/html/pulleys___belts.html
Your description of 180° rotation sounds right to me. I believe adding resistors to the pot will only limit the range, not increase it. I have not tried it though. The servo has a mechanical stop on the final gear that would need to be removed if it were possible to extend the range.
Thanks for the help
I’ll see what I can come up with using those gears