You need a Digital I/O device and actuators. You will need some interface circuit to take the DIO input and convert the voltage level to drive the actuator. The ULN2003 does this quite well. Use Labview to output ones and zeros on the DIO, which will turn the actuators on and off. The actuators must be positioned to push your UUT button/membrane/switch when fully extended. Look at the Labview examples for DIO, and look at a data sheet for the ULN2003. This should get you started.
