Pressure sensing controller using Stress Ball
Of course it is possible. You can measure the squeezing force for example with an force sensitive resistor (FSR sensor) (see Adafruit example) or even built your own (fabric) pressure sensor (see www.kobakant.at). All you need is a microcontroller with an ADC. For example every Arduino board has this capability. In addition you can use a motor shield/board or built your own circuit to control the motor system.