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I have a small table-like platform with two legs. Underneath each, I need to measure the amount of force. I want to use the difference between the two force measurements to estimate the platform's center of gravity.

What's a good sensor to use for this? Looking through suppliers Digikey, all the sensors that can handle a large amount of sustained force are either enormously expensive or way too large. Is there another way to measure force without bulky discrete sensors?

As a cheaper alternative, I was thinking of placing the platform on a low-profile seesaw, with a rotary potentiometer at the fulcrum, and springs under either end. The seesaw would tilt in proportion to the offset of the platform's center of gravity, and this could be measured with the potentiometer. It could do the same measurement as a $200 force sensor at a fraction of the cost. The only problem is that most potentiometers distribute their range of values across 360 degrees, whereas I need all those values within the range of 1 degree.

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  • $\begingroup$ The title asks for a "high impact" sensor, but nothing in the question describes anything about impact. Question just talks about cost and size. So are you looking for a sensor that can sustain impacts or not? Either way, please edit either the title or the question so its clear. $\endgroup$ – Daniel K Aug 7 '18 at 23:08
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get you a battery-operated digital (i.e.,electronic) bathroom scale at a goodwill store. Disassemble it; you will find several compressive strain gauges inside along with the associated electronics. the electronics are cleverly designed to determine the weight of the object on the platform even if that weight is off-center, by artfully polling each sensor , A-to-D converting each, and feeding the results into a clever algorithm.

You should be able to hack this into something that might suit your purpose. Of course, the easy way would be to buy one bathroom scale for each leg and then hack the display driver on each to extract a decimal value for the weight based on which segments in the display are energized.

whatever you do, have fun!

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You can attach a low price Laser pointer to your table and read angles off a board positioned on one side as far as is needed to give you resolution in the range you work with, similar triangles.

Amazon sells a pack of three for $8.03. in different colors.

You just need to attach them secure and approximately level, because of your small angle variation anticipation, it doesn't matter if they are not calibrated to be perfectly level. But you only need to wrap a tape around the switch to keep it on.

3 pieces Laser Torch

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