How can I measure the force applied to something?

[Amarah]

Homework Statement

For a personal project I am doing, I want to test a range of forces in the horizontal direction, and see how the device I created reacts at different forces. So for example, if I want to apply 5N specifically to a device, to see how it reacts under that force, how would I go about applying it? Like applying a specific amount of force. Because I can measure displacement, and I can push on my device with my own fingers, but I don't know what amount of force I am pushing with. I want to know specifically the amount of force.

Homework Equations

The Attempt at a Solution

Something like a dynamometer, but instead of knowing the force being applied to the dynamometer, I want to replace the dynamometer with my device. And I know spring force meters can measure a force, but I want to take a measured force and apply it to something.

 

[Tom.G]

Put a platform scale between your finger and the device and push.

Connect a pull scale (fish scale) to the far side of your device and pull.

 

[Amarah]

Put a platform scale between your finger and the device and push.
View attachment 222737

Connect a pull scale (fish scale) to the far side of your device and pull.
View attachment 222738

I considered these previously, but I don’t think they’ll work. My device is in a symmetrical (along the y-axis) oval shape, and in typical use, force would be applied to both the long sides (along the x-direction). So I want to apply a force to one end and see how far inwards it will deform (which would also theoretically be happening on the other end since symmetrical...)

So for the latter, I want a push force against the device, so that wouldn’t quite work. For the former, it wouldn’t really reflect the testing conditjons I want, I think. I don’t want to completely smush the device.

 

[jrmichler]

You could push with an air cylinder. Apply a known air pressure using a regulator to the piston (which has a known area), then push until the piston is off the stops. If you want high accuracy, use a low friction air cylinder such as http://airpot.com/product-category/applications/apply-a-precision-force/ or https://www.marshbellofram.com/bellofram-pcd/files/2012/07/C_Cylinders_p45_56.pdf. The end of an air cylinder rod is threaded, you can screw on an extension.

 

[berkeman]

So for the latter, I want a push force against the device, so that wouldn’t quite work. For the former, it wouldn’t really reflect the testing conditjons I want, I think. I don’t want to completely smush the device.

How about a Push/Pull meter like this one?

http://www.4physics.com/catalog/images/ForceMeterPush.png

 

[CWatters]

Combination of string pulleys and weights?

 

[Amarah]

How about a Push/Pull meter like this one?

http://www.4physics.com/catalog/images/ForceMeterPush.png
View attachment 222789

That looks promising! Would a push force gauge be similar? I think that could work.

 

[berkeman]

That looks promising! Would a push force gauge be similar? I think that could work.

That *is* a push force gauge... Notice how it is being used to push that box UP the ramp...?

Use the link to the picture to get to the website. It looks like they sell several different styles of force gauges.

 

[Amarah]

That *is* a push force gauge... Notice how it is being used to push that box UP the ramp...?

Use the link to the picture to get to the website. It looks like they sell several different styles of force gauges.

Thank you so much!