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General project discussion / help
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By SkiingBanana
#193204
I am currently working on a project with the goal of measuring mass in space using a centrifuge to calculate mass from force and angular velocity. I am not very experienced in programming or electronics, so I need some help.

The basic principal of this project revolves (hehe) around the equation that relates angular velocity, radius, and centripetal force. This equation is Fcentripetal=m((v^2)/r) where Fcentripetal is the centripetal force, m is mass in Kg, v is angular velocity in m/s, and r is radius in meters. My setup consists of a .25 m diameter cylinder spinning at 30 rpm. The mass of the objects will be no greater than 100 g and needs to be accurate to a gram. Due to the lack of gravity in space and the low RPM, in my setup, one gram of mass only applies .00125 newtons (approximately .1 g) of force on the side of the cylinder. The cylinder will be rotated by a motor that has an encoder on it to get a very accurate RPM.

The main problem I have with this project is my sheer lack of experience in electronics and programming.

Concerning measuring force, I need to get a "force sensor" that would be able to measure up to 30 g with an accuracy of .1 g. I have looked at load cells and all of those seem to be too inaccurate and sense forces much larger than what I am looking for. Can anybody point me in the right direction to find a sensor that can be able to measure these kinds of forces?
By SkiingBanana
#193217
Ok, I have looked at that and it is quite pricey.

I was wondering if it was possible to use sparkfun's strain gauge to measure the mass and then use an amplifier to make the data more accurate, does anybody know if i can "stack" amplifiers? or at least put a few of them together to get a much more accurate sensor?