I'm trying to design a device that can stretch a tissue sample of set length, right now about 2 mm, to desired stretch ratios. This will be controlled using a interface where the user can input their desired ratio, and the controller will tell a 6 in stroke WindyNation linear actuator to move to a position based on the input ratio. The controller also needs to communicate with a force sensor and display the force that is being exerted on the sample.
For this type of problem, is it better to use an Arduino, Raspberry Pi, or both to power the controller? I've found that the Pi won't be very good due to issues with timing. Will this be a serious issue?