A rotary blade sharpness tester is provided. The rotary blade sharpness tester comprises a rotary blade holder, supporting means for supporting a cuttable material, a moving mechanism to cause relative movement between the blade holder and the supporting means, and hence the cuttable material when supported on the supporting means, an activation means to activate a rotary blade held in the rotary blade holder and cause rotation of the blade before the blade comes into contact with the cuttable material. During the relative movement between the blade holder and supporting means the rotary blade movably contacts the material. The sharpness tester further comprises force measuring means operable in use to measure the force of the rotary blade on the cuttable material.

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.

A drop tower apparatus and method of use is provided. The drop tower apparatus includes a base, a frame, a top member, rails, a sled, a triggering system, and a test fixture. The frame extends from the base. The top member is disposed on the frame opposite the base and has a winch. The rails extend from the base to the top member and are disposed within the frame. The sled is configured to slide vertically along the length of the rails and is releasably connected to the winch of the top member. The test fixture is configured to receive a sample for testing. The winch of the top member raises the sled to a desired height, the sled is released at the desired height and slides along the rails resulting in an impact on a sample placed in the test fixture.

A system, method and apparatus for determining a parameter of a fluid is disclosed. Measurements are obtained of a temperature of the fluid and a pressure of the fluid. A material is disposed in the fluid, and an actuator applies a stimulation pulse at a selected frequency to the material to generate an oscillation in the material. A measurement device measures a parameter of oscillation of the material in response to the stimulation pulse, the parameter of oscillation being affected by the fluid in which the material is disposed. A processor determines the parameter of the fluid from the measured parameter of the oscillation, the temperature measurement and the pressure measurement.

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.

There is described a system for characterizing a physical property of a sample. The system generally has a microelectromechanical system (MEMS) device having a framework, a shuttle member extending along a longitudinal orientation within the framework, a shuttle actuator having obliquely extending arms extending between the framework and the shuttle member, the shuttle actuator configured for expanding the arms upon application of electricity thereacross, said expanding applying a force onto the shuttle member and moving the shuttle member at least partly in the longitudinal orientation, and a socket positioned adjacent a tip of the shuttle member; and a MEMS chip receiving the sample and being configured for insertion into the socket, whereby, when the MEMS chip is received in the socket and loaded with the sample, the force applied onto the shuttle member is transferred into stress internal to the MEMS chip via the tip of the shuttle member.

An apparatus and method for measuring the impact performance of a target material comprising a hollow structure comprising an outlet end located above a target. The hollow structure is dimensioned to allow free movement of a drop test object through the outlet end. A trigger is located proximate to the outlet end and a retaining member is located proximate to the outlet end and coupled to hollow structure. The retaining member is configured to retain the drop test object in the hollow structure upon activation of the trigger.

The invention provides a lead titanate coating and a preparing method thereof. According to the method, mixed powder is sprayed on the surface of a matrix, and through polarization, the lead titanate coating is acquired. The mixed powder comprises PbTiO.sub.3 powder, PbO powder and Al powder. Lead titanate (PbTiO.sub.3) is a kind of ferroelectric material, and can be used for preparing a piezoelectric sensor. Besides, the PbO powder and the Al powder are added, so that the piezoelectric property of the lead titanate coating can be improved. Since the lead titanate coating prepared by the present invention can be combined with the matrix closely and the intensity of piezoelectric signal is high, it can be widely applied to mechanical parts, such as a piston ring, a cylinder, a gear, and the like, to dynamically monitor the service situations of the parts better.

A support apparatus includes a force sensing array positioned thereon that includes multiple layers of material that are arranged to define an elastically stretchable sensing sheet. The sensing sheet may be placed underneath a patient to detect interface forces or pressures between the patient and the support structure that the patient is positioned on. The force sensing array includes a plurality of force sensors. The force sensors are defined where a row conductor and a column conductor approach each other on opposite sides of a force sensing material, such as a piezoresistive material. In order to reduce electrical cross talk between the plurality of sensors, a semiconductive material is included adjacent the force sensing material to create a PN junction with the force sensing material. This PN junction acts as a diode, limiting current flow to essentially one direction, which, in turn, reduces cross talk between the multiple sensors.

A test system includes a frame. A hydraulic actuator is mounted to the frame and is configured to support a test specimen. A piezoelectric actuator is configured to apply a force to the test specimen. A controller is configured to excite the piezoelectric actuator and provide an indication of force generated by the piezoelectric actuator by measurement of current or charge provided to the piezoelectric actuator.