Project: Controlled release of a small weight

I am trying to design a device that will lower a small weight in a controlled manner to depress the canister of an inhaler. I was thinking of using an FSR (force sensitive resistor) as an input for when the weight should be released, but I'm not sure what Arduino capabilities exist that would allow the communication from an FSR to lower or release a weight.
What are some mechanical-related capabilities that might be relevant here?

http://www.ladyada.net/learn/sensors/fsr.html

Couldn't you get the arm of a servo to press the canister rather?

Servo is nice and easy to control, they come in different sizes and strengths.

It is unclear, to me, if the FSR is to start the sequence or sense when the button is pressed and release the button.

Also Sparfun has them : Flex / Force - SparkFun Electronics

A force sensitive resistor is not very accurate to measure weight. It is easy to use with an Arduino.
On the other hand a load cell is very accurate, but is not so easy, since extra hardware is needed.

I think this is an XY problem.

If the objective is to squirt the inhaler, then dropping a weight on it might not be the best solution.

@cehintz, what is the actual objective here?

@ JimboZA The actual objective is to squirt the inhaler.

cehintz:
@ JimboZA The actual objective is to squirt the inhaler.

.... in which case I'd investigate a servo. You would need to fashion some kind of bracket to hold it, and position it so that the lever thing presses firmly on the inhaler.

This might inspire you 8)

You could use the mechanism from one of those automatic aerosol air-fresheners, or design something similar.