The present disclosure relates to an apparatus and methods for applying a force on a sample. In particular, the present disclosure relates to a stress cell (200) comprising a frame (205); an actuator arrangement (210) coupled to the frame; and a coupler (220) for coupling the actuator arrangement to the sample (230). The coupler (220) includes a first coupler portion connected to the actuator arrangement (210) and a second coupler portion connectable to the sample (230). The first coupler portion is flexibly coupled to the frame. The actuator arrangement (210) comprises a first element (214) having a first variable length and a second element (212) having a second variable length, and is adapted to vary a difference between the first length and the second length to provide the force.

The present disclosure relates to an apparatus and methods for applying a force on a sample. In particular, the present disclosure relates to a stress cell (200) comprising a frame (205); an actuator arrangement (210) coupled to the frame; and a coupler (220) for coupling the actuator arrangement to the sample (230). The coupler (220) includes a first coupler portion connected to the actuator arrangement (210) and a second coupler portion connectable to the sample (230). The first coupler portion is flexibly coupled to the frame. The actuator arrangement (210) comprises a first element (214) having a first variable length and a second element (212) having a second variable length, and is adapted to vary a difference between the first length and the second length to provide the force.

The invention discloses a bio-MEMS transducer comprising a cultured myotube and a piezoelectric microcantilever having the myotube attached thereto along a lengthwise extent of said microcantilever. The transducer may include an input/output processor operably connected with said piezoelectric microcantilever to process electrical signals received therefrom and to send electrical signals thereto. The invention may operate as a biosensor wherein the attached myotube contracts on contact with a sensed agent, the myotube contraction deflecting the microcantilever to generate a piezoelectric signal therefrom. The invention may also be used as a biosensor for quantitating physiologic response to an agent by measuring deflection of the cantilever caused by myotube contraction elicited by contact with the agent; and correlating the measurement to effectiveness of the sensed agent in causing a myotube physiologic response. The bio-transducer is a bioactuator when an applied electrical signal causes the piezoelectric microcantilever to deflect, thereby actuating the attached myotube.

A MEMS-nanoindenter chip performs nanoindentation on a specimen. The MEMS-nanoindenter chip has an intender probe joined with an indenter tip. The indenter tip indents into the specimen. A reference probe is joined with a reference tip, the reference tip touches the specimen. Sensing capabilities are provided to measure the position of the indenter probe relative to the reference probe. The MEMS-nanoindenter chip enables highly accurate measurements since the frame stiffness is not part of the measurement chain any more. Furthermore, thermal drift during the nanoindentation is considerably reduced.

A dynamic mechanical analysis system provides an actuator that imparts expansion and contraction forces (e.g. shear force) to a viscoelastic material at high frequencies. Such high frequency analysis allows for the direct and accurate measurement of the characteristics of the material at high expansion/contraction frequencies directly, without the use of additional predictive analysis techniques, such as time-temperature superposition. The system also utilizes a clamping system, whereby two different sections of the viscoelastic material are held in place between by a pair of fixed clamps and a force member that is moved by the actuator. As such, the system is able to subject the viscoelastic material sample to simulated road conditions to identify various performance properties associated with the material sample.

A device for evaluating working surface fretting wear characteristics comprises a bottom holder with a sample secured thereto, springs displacing in the X and Y direction, multilayer piezo elements moving in the X, Y, and Z directions, a housing, a top plate/holder, a linear air bearing housing, a spherical upper sample, a linear air bearing shaft, a three-way force sensor, a moving support of the flat air bearing and the flat air bearing housing, a high frequency generator, an amplifier, a controller, an electrical filter, a computer, a force sensor signal amplifier, and a flat air bearing. Instead of springs, it can comprise additional multilayer piezo elements moving in the X and Y directions. The device performs testing surface wear under conditions nearer to actual fretting wear conditions, continuously observing friction pair condition changes during testing and evaluating wear characteristics of the tested material more accurately.

A method and device for electro-thermo-mechanical tensile testing of wires is disclosed. The device includes a sample frame having upper and lower parts, with the upper part coupled to the lower part through a plurality of sacrificial supports, the upper and lower parts each having an electrical contact pad. The upper and lower parts are electrically non-conductive. The device also includes a wire sample with tracking beads, the wire sample affixed to the upper and lower parts such that the electrical contact pads of the upper and lower parts are communicatively coupled through the wire sample. The device also includes a piezo actuator coupled to the upper part, a weight coupled to the lower part, a power supply configured to pass a current through the wire sample, an electronic balance beneath the weight, and a digital camera pointed at the tracking beads of the wire sample.

The present invention provides a method of surely detecting a crack in piezoelectric elements regardless of size of the crack. The method includes applying voltage to a first piezoelectric element of a pair of piezoelectric elements to cause deformation in the first piezoelectric element, forcibly deforming a second piezoelectric element of the pair of the piezoelectric elements to generate voltage from the second piezoelectric element according to the deformation of the first piezoelectric element, finding a transfer function of the pair of the piezoelectric elements based on values of the applied voltage and the generated voltage, and detecting presence or absence of a crack in the pair of the piezoelectric elements based on an objective value obtained from the found transfer function.

Described herein is a soft leaf tissue elasticity tester comprising a modified piezoelectric finger (PEF) sensor and a sample pad useful for rapidly and sensitively screening plants for disease by quantifying changes in tissue elasticity and/or stiffness as an indication of plant disease. Also described is a method of screening plants for disease by quantifying changes in tissue elasticity and/or stiffness as an indication of infection. The tissue elasticity measurements used to screen plants for disease may be performed using the soft tissue elasticity tester described.

The invention discloses a bio-MEMS transducer comprising a cultured myotube and a piezoelectric microcantilever having the myotube attached thereto along a lengthwise extent of said microcantilever. The transducer may include an input/output processor operably connected with said piezoelectric microcantilever to process electrical signals received therefrom and to send electrical signals thereto. The invention may operate as a biosensor wherein the attached myotube contracts on contact with a sensed agent, the myotube contraction deflecting the microcantilever to generate a piezoelectric signal therefrom. The invention may also be used as a biosensor for quantitating physiologic response to an agent by measuring deflection of the cantilever caused by myotube contraction elicited by contact with the agent; and correlating the measurement to effectiveness of the sensed agent in causing a myotube physiologic response. The bio-transducer is a bioactuator when an applied electrical signal causes the piezoelectric microcantilever to deflect, thereby actuating the attached myotube.