Abstract: An electromagnetic motor includes a stator and an armature arranged to move substantially linearly relative to the stator in an intended direction during operation of the motor. A first and second flexure are connected to a first end of the armature. Each flexure has a longest portion which lies substantially in a plane that intersects a plane in which the armature lies at a substantially right angle. The flexures allow motion of the armature in the intended direction while resisting motion of the armature in one or more other degrees of freedom.

Abstract: This document provides systems and methods for testing of various kinds of valves. For example, this document provides systems and methods for accelerated life testing of prosthetic heart valves.

Abstract: An apparatus includes an electric machine. The electric machine includes an internal housing, an armature coil disposed within the internal housing and separated from the internal housing by a gap, and a magnetic core associated with the armature coil. The apparatus also includes a fan configured to cause air to flow in the gap between the armature coil and the internal housing.

Abstract: A system for applying mechanical stimulation to a biologic sample includes a first biologic sample chamber having a biologic sample holder therein, a support structure for holding the first biologic sample chamber, and a first actuator that can supply a mechanical load to a biologic sample held by the biologic sample holder. The actuator is configured to move into a first position proximate to the chamber in which the actuator can transmit the load to the biologic sample via a first transmission path that includes the biologic sample holder. A controller is configured to automatically move the first actuator into the first position.

Abstract: Stability of a control system for a materials testing system using specified filter parameters is confirmed by inputting to the control system a test signal having a predetermined waveform, automatically monitoring the output of the materials testing system, and automatically comparing the output to a threshold. If the output exceeds the threshold, a first action is taken. If the output does not exceed the threshold, input of a command signal to the control system is permitted.

Abstract: An electromagnetic motor includes a stator and an armature arranged to move substantially linearly relative to the stator in an intended direction during operation of the motor. A first and second flexure are connected to a first end of the armature. Each flexure has a longest portion which lies substantially in a plane that intersects a plane in which the armature lies at a substantially right angle. The flexures allow motion of the armature in the intended direction while resisting motion of the armature in one or more other degrees of freedom.

Abstract: An apparatus includes an electric machine. The electric machine includes an internal housing, an armature coil disposed within the internal housing and separated from the internal housing by a gap, and a magnetic core associated with the armature coil. The apparatus also includes a fan configured to cause air to flow in the gap between the armature coil and the internal housing.

Abstract: In a mechanical test system, a method of compensating for acceleration induced load error in a load sensor in a mechanical communication with a component comprises measuring an acceleration of the component to obtain an acceleration measurement. A load sensor measures a force applied by the mechanical test system to a test sample in substantially a same direction of the acceleration to obtain a force measurement. The force measurement is modified with a transfer function that includes at least one of a gain correction and a phase correction to compensate for an error value in the force measurement attributed to movement of at least the load sensor when the force is applied to the test sample.

Abstract: A securing apparatus includes a housing, a cam member, and a movable device that can be moved in a first direction to engage a first surface of the cam member to cause the cam member to move from a first position to a second position. When the cam member is in the first position, first and second movable members can be moved relative to the housing. When the cam member is in the second position, second and third surfaces of the cam member press respectively against the first and second movable members to trap the first and second movable members respectively between the second and third surfaces of the cam member and the housing such that the first and second movable members are fixed relative to the housing.

Abstract: A chamber assembly for testing a valve includes a proximal chamber portion that defines a proximal interior space, and a distal chamber portion that defines a distal interior space. The distal interior space includes a gas space. When a liquid is inserted into the proximal and distal chambers there is an interface between the liquid and a gas in the gas space. A valve holder is disposed adjacent to the proximal interior space and the distal interior space. The valve holder is configured to receive the valve in a bore of the valve holder. A shortest distance between a center of the valve when in the bore and the interface is at least about 45 mm.

Abstract: An apparatus for fatigue testing an article includes a base having a platform for receiving an article to be tested, a shaft extending toward said platform for applying a force to said article, a coupling assembly connected to said shaft, said coupling assembly comprising a joint that pivots about an axis, and flex pivots disposed to be aligned with said axis about which said joint pivots.

Abstract: A bioreactor system includes a sample chamber capable of receiving a specimen and a cover which can be placed on the chamber to enclose the specimen within the chamber. A first member is movable between (i) a closed position in which the member restricts the cover from being moved away from the chamber in a first direction, and (ii) an open position in which the member does not restrict the cover from being moved away from the chamber. When the first member is in the closed position there is a substantially liquid proof seal between the cover and the chamber.

Abstract: A rheometer includes a holder assembly for coupling a test specimen to a motor assembly to effect rotational strain in the test specimen while enabling the determination of axial displacement effected by the test specimen normal to the direction of the rotational strain, the holder assembly having a first member coupled to the test specimen, a second member coupled to the motor assembly, and a suspension arrangement coupling the first member with the second member for simultaneous maximum resistance to relative rotational displacement between the first and second members and minimum resistance to relative axial displacement between the first and second members.

Abstract: The invention relates to a platen to be used with a sample tray of an automatic sampler. According to an aspect, the platen includes both electrically conductive and reflective areas that can be used to calibrate the sample tray. According to another aspect, calibration of the sample tray can be performed in all three dimensions. According to another aspect, the platen is used to calibrate the sample tray, including its height and the location of its wells. The platen may include electrically-responsive (i.e., conductive) and optically-responsive (i.e., reflective) areas that can be sensed by electrical sensors and optical sensors in order to compute the coordinates of representative wells.

Abstract: The invention relates to an automatic sampler device. According to one aspect, the automatic sampler includes a cell having a sample platform and a reference platform; a sample tray; and a sample arm. The sample tray has wells into which sample pans and reference pans are inserted. The geometry of the automatic sampler device permits the sample platform, the reference platform, and the wells in the sample tray to be accessed by the sample arm along a common arc. According to another aspect, the automatic sampler device includes a sample tray with wells, a sample arm, and a gripper device. The gripper device has gripping fingers. The gripping fingers open or close in a manner that tends to center objects grasped by the gripper device. According to another aspect, the automatic sampler device includes a sample tray with wells, a sample arm, and a gripper device. The sample arm has an optical sensor and an electrical sensor.

Abstract: The present invention is directed to a technique for performing calibration of an automatic sampler device. According to an aspect, the automatic sampler device includes a cell with a sample platform and a reference platform; a sample arm; a sample tray, and a platen. The sample tray includes wells into which pans are inserted. The platen may include conductive and/or reflective areas for calibration. The sample arm has an electronic sensor and an optical sensor. The electrical sensor and the optical sensor are used to calibrate the positions of one or more of: the sample platform, the reference platform, and a well. According to another aspect, autocalibration is optimized by adjusting autocalibration results with a set of stored offset coefficients. The offset coefficients are generated by performing a manual calibration. The difference between the results of the manual calibration and an autocalibration are stored as offset coefficients.

Abstract: The present invention is directed to a technique for performing calibration of an automatic sampler device. According to an aspect, the automatic sampler device includes a cell with a sample platform and a reference platform; a sample arm; a sample tray, and a platen. The sample tray includes wells into which pans are inserted. The platen may include conductive and/or reflective areas for calibration. The sample arm has an electronic sensor and an optical sensor. The electrical sensor and the optical sensor are used to calibrate the positions of one or more of: the sample platform, the reference platform, and a well. According to another aspect, autocalibration is optimized by adjusting autocalibration results with a set of stored offset coefficients. The offset coefficients are generated by performing a manual calibration. The difference between the results of the manual calibration and an autocalibration are stored as offset coefficients.

Abstract: The invention relates to a gripper device. According to one aspect, the gripper device includes fingers with grasping ends. The gripper device includes a mechanism to cause the grasping ends to open and close. When the mechanism is engaged, the grasping ends open and close to define a circumference. According to another aspect, the gripper device includes fingers, an upper flat member, and a lower flat member. The fingers have grasping ends. The fingers are inserted into the upper flat member and lower flat member. When the upper flat member is rotated relative to the lower flat member, the grasping ends of the fingers open and close. According to another aspect, a gripper assembly has a gripper device with fingers and a rotating member. The gripper assembly also has a motor and mechanism for rotating the rotating member. The gripper device opens or closes the grasping ends in response to the rotation of the rotating member.

Abstract: The invention relates to a sample tray to be used by an automatic sampler having a sample arm. According to an aspect, the sample tray includes wells that can be accessed by a sample arm along a common arc of rotation, without moving the sample arm in and out. According to another aspect, the sample tray has several concentric rows of wells for holding sample pans and reference pans. Each row of wells lies along an inner circumference of the sample tray. The rows are placed so that when the sample tray is rotated, every well can be located on a common arc of rotation relative to a sample arm. According to another aspect, a well in a sample tray is configured with a pan receiving area and finger receiving areas. Gripper fingers can be extended into the finger receiving areas to access pans of different sizes.

Abstract: A liquid nitrogen cooling assembly incorporating a liquid detector which feeds back to control the nitrogen supply is disclosed. A pressure-controlled nitrogen source (e.g., a dewar) feeds liquid nitrogen to a heat exchanger mounted to a differential scanning calorimetry (DSC) cell. The DSC cell is cooled as liquid nitrogen in the heat exchanger contacting the cell is vaporized into nitrogen gas. The exhaust (nitrogen gas and, occasionally, nitrogen liquid) is fed to a liquid detection/evaporator assembly. If liquid nitrogen is detected in the exhaust by the liquid detection/evaporator assembly, an indication is fed back using a liquid detection feedback loop to a pressure control device. The pressure control device reduces the amount of pressure on the nitrogen source in order to eliminate liquid in the exhaust. When there is liquid in the exhaust, the liquid detection/evaporator assembly also collects and vaporizes the exhaust liquid so that it can be properly vented to atmosphere in gas form.