Compensated Mechanical Testing System

A mechanical testing system, comprising:

• a frame,
• a stage for holding a sample,
• an arm for pressing a tool against a surface of the sample,
• a primary actuator connected to the frame for applying a primary force and driving the tool into the sample, thereby causing the frame to flex, wherein the primary actuator is at least one of electromagnetic, electrostatic, piezoelectric, hydraulic, mechanical, and pneumatic,
• a displacement sensor for measuring a displacement value comprised of two components, the first component including a distance traveled by the tool into the sample as the primary force is applied, and the second component including a measure of a degree of flex of the frame as the primary force is applied, and
• a plurality of compensating actuators connected to the frame for applying a compensating force that reduces the second component of the displacement value, wherein the compensating force corrects an apparent stiffness of the frame to about ten million newtons per meter.

A method for testing at least one of a hardness and an elastic modulus of a sample, the method comprising the steps of:

• placing a sample to be tested on a stage that is supported by a frame,
• using a primary actuator that is supported by the frame to apply a primary force and drive a tool into a surface of the sample, thereby causing the frame to flex,
• measuring a displacement value with a displacement sensor, the displacement value comprised of two components, the first component including a distance traveled by the tool into the sample as the primary force is applied, and the second component including a measure of the flex of the frame as the primary force is applied, and
• applying a compensating force with a compensating actuator that is connected to the frame, where the compensating force reduces the second component of the displacement value.