How to attach a potentiometer to a servo motor shaft

How much torque required to turn the valve? How many degrees from full open to closed? Have you thought about proportional flow hydraulic solenoid valves?

outsider:
How much torque required to turn the valve? How many degrees from full open to closed? Have you thought about proportional flow hydraulic solenoid valves?

The valves are built in mechanical.
The other queations i just havent had a chance to figure out. Im juat now starting to get things together

To a certain extent, some of the information can be obtain by simple manual testing.
Example, you have a valve that has a shaft. You clamp a pair of vise grips on the shaft and open and
close the valve by hand. Then you remove the visegrips from the valve and clamp on the motor shaft and turn on the motor and tell it to turn (slowly) one way or the other , then you try to stop that motor from turning by holding onto the vise grips and mentally compare the force needed to turn the valve with the force needed to stop the motor.

Additionally there are other more accurate ways to measure the torque, like attaching a pully to the shaft
and having the motor lift a weight, (like a bucket you add or remove water from and then weigh the bucket. ) The converse of this is attach a pulley to the shaft of the valve and measure the weight of the amount of water needed to open and close the valve and then see if the motor can lift that amount of water (or sand, or rocks, or diamonds, or coins etc)
At the end of the day, you don't need to know the torque spec in Nm. All you need to do is find a motor that is capable of performing the required task and then look at the spec sheet for that motor and whatever it is , it exceeds the torque spec for you task.

raschemmel:
To a certain extent, some of the information can be obtain by simple manual testing.
Example, you have a valve that has a shaft. You clamp a pair of vise grips on the shaft and open and
close the valve by hand. Then you remove the visegrips from the valve and clamp on the motor shaft and turn on the motor and tell it to turn (slowly) one way or the other , then you try to stop that motor from turning by holding onto the vise grips and mentally compare the force needed to turn the valve with the force needed to stop the motor.

Additionally there are other more accurate ways to measure the torque, like attaching a pully to the shaft
and having the motor lift a weight, (like a bucket you add or remove water from and then weigh the bucket. ) The converse of this is attach a pulley to the shaft of the valve and measure the weight of the amount of water needed to open and close the valve and then see if the motor can lift that amount of water (or sand, or rocks, or diamonds, or coins etc)
At the end of the day, you don't need to know the torque spec in Nm. All you need to do is find a motor that is capable of performing the required task and then look at the spec sheet for that motor and whatever it is , it exceeds the torque spec for you task.

Fish scale?

birddseedd, when will you stop opening threads in the forum before you have figured out what you want?

You want to control a valve both by hand and by a motor, right?

You didn't even use the word "valve" before your FIFTH post and another TEN answers from users that spent their time trying to help you.

couka:
birddseedd, when will you stop opening threads in the forum before you have figured out what you want?

You want to control a valve both by hand and by a motor, right?

You didn't even use the word "valve" before your FIFTH post and another TEN answers from users that spent their time trying to help you.

Thats because im not controlling the valve itaelf but the handle bars their attached to.

I am inclined to request/demand a drawing but I fear that probably doesn't exist either.

raschemmel:
I am inclined to request/demand a drawing but I fear that probably doesn't exist either.

I could just take pictures of it.

It' your dime.

birddseedd:
I could just take pictures of it.

33 replies in I'd say it's about time you start doing those things. Or do you really have the feeling you're getting anywhere with this thread? I for one don't.

wvmarle:
33 replies in I'd say it's about time you start doing those things. Or do you really have the feeling you're getting anywhere with this thread? I for one don't.

I'm learning. that's the point. I've also been dealing with an emergency c section. But i do have a grasp on what type of servo will allow me to read position with it being powered down. Of course, now that i'm starting to put all this together, i'm starting to question everything. pro's and con's to everything

raschemmel:
I am inclined to request/demand a drawing but I fear that probably doesn't exist either.







so. if i build a bracket allowing me to attach at one of the two bolts, i measured 10 lbs of force to go forward 3.5 inches over about 4 seconds and 15 lbs backward about 2.5 inches over about 2 seconds.

so i need to figure out what strength servo i can use to obtain this. i can put a lever on the shaft to get the throw i need, but that means a stronger servo will be needed at the short end of a lever.

I don't see that working witha motor.
That looks more like acuator application.

raschemmel:
I don't see that working witha motor.
That looks more like acuator application.

that would make some things a lot easier. but the problem that i run into is that you can not move an actuator manually. I need to be able to run the mower by hand while recording the positions, then i know the positions and times that need to be sent back to the motor. to use an actuator i would have to build controls with joysticks and run the machine that way. which can be done, just isn't a great way of doing it.

15 lbs of force on the handle that appears to be at least 16 inches from the pivot point? 20 pound feet of torque? Oh my, looks like a big gearmotor with an electromagnetic release clutch for manual operation.

outsider:
15 lbs of force on the handle that appears to be at least 16 inches from the pivot point? 20 pound feet of torque? Oh my, looks like a big gearmotor with an electromagnetic release clutch for manual operation.

how do i work with the draw weight i measured? how do i convert it to something that is repeatable to motor specs?

That 20 foot-pound is your motor torque specification.

wvmarle:
That 20 foot-pound is your motor torque specification.

How do i calculate that. i apologize for asking. i just need to know how to do it so next time i do a project like this i won't have to ask.

20 foot-pound

birddseedd:
How do i calculate that.

It's the product of the force and the distance at which it acts from the pivot.

So 15lbs at 16" is 15 x 1.33' = 20