A test fixture for applying a prescribed displacement to a material includes a first and a second portion, a first and a second adjustable pin, and an actuator. The first portion includes a first pin that to engages the material at a first location on the material. A second pin is engages the material at a second location on the material. A third pin engages the material at a third location on the material. The first adjustable pin holds the material against the second pin at the second location. The second adjustable pin holds the material against the third pin at the third location. The actuator is adapted to configure a relative position between the first pin and the second and third pins.