Compliant mechanisms

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cox
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Joined: Wed Nov 26, 2014 11:37 pm

Compliant mechanisms

Post by cox »

I found this interesting, and thought it might be for others on here.

https://www.youtube.com/watch?v=97t7Xj_iBv0
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DeepSOIC
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Re: Compliant mechanisms

Post by DeepSOIC »

One of the most fascinating compliant mechanism I ever touched was one in a precision balance.
It's a lever system, probably EDM-machined from a single block of ?bronze?.
WP_20141224_22_06_25_Pro_reduce.jpg
WP_20141224_22_06_25_Pro_reduce.jpg (553.25 KiB) Viewed 977 times
balance closeup.jpg
balance closeup.jpg (584 KiB) Viewed 977 times
mlampert
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Re: Compliant mechanisms

Post by mlampert »

Came across compliant mechanisms a few weeks ago and am massively fascinated by them. Would you know how this balancer works?
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DeepSOIC
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Re: Compliant mechanisms

Post by DeepSOIC »

mlampert wrote: Sat Mar 30, 2019 5:21 pm Would you know how this balancer works?
Of course I do.

Here's a crude animation of the lever movement.
balance-compliant-lever.gif
balance-compliant-lever.gif (372.24 KiB) Viewed 944 times
The weight to be weighed is put onto the slowly moving group on the right. There is a voice coil motor on the end of the long lever (on the left side). And an optical position sensor. The motor and the sensor are tied in a feedback loop, so the lever never moves (the motor compensates the force created by weight being measured). ADC samples the current flowing through the motor, and converts it into a displayed value.
mlampert
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Re: Compliant mechanisms

Post by mlampert »

Awesome - thanks a lot!
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