Abstract: System for establishing a surface shape. The system includes a compliant substrate including the surface and having a reverse side, and a plurality of discrete actuators engaging the reverse side and arranged in a selected pattern to control the surface shape as individual discrete activators are activated. It is preferred that the actuators have multiple discrete stable states of elongation. A particularly preferred embodiment uses actuators that are binary with two stable states of elongation.

Abstract: Parabolic Mirror. The mirror includes a flexible material with a reflective surface and a rear surface. A flexible band is in contact with the rear surface of the flexible material. The bending stiffness of the band as a function of distance along its length is selected so that the band and the flexible material in contact therewith assume a parabolic shape when ends of the band are moved toward one another. In a preferred embodiment, the bending stiffness of the band is achieved by controlling the second moment of area of the band along its length. The second moment of area may be adjusted by altering the width of the band along its length or by altering the thickness of the band along its length, or a combination of the two.

Abstract: Photovoltaic-powered reverse osmosis system. The system includes a photovoltaic panel for generating electricity and includes a heat exchanger in thermal contact with the photovoltaic panel. The salt-containing feed water is fed to a reverse osmosis unit to produce clean water therefrom. Fluid circuitry, including a pump, circulates the feed water through the heat exchanger to cool the photovoltaic panel and to heat the feed water. It also delivers the heated feed water to the reverse osmosis unit for desalination. Cooling the solar panel and heating the RO feed water increases the total amount of clean water produced. In a preferred embodiment, a thermal controller manages the temperatures of the photovoltaic panel and the feed water by controlling the flow of feed water through the fluid circuitry. The photovoltaic panel temperature is minimized and the temperature of the feed water is maximized subject to a constraint on maximum feed water temperature.

Abstract: System for establishing a surface shape. The system includes a compliant substrate including the surface and having a reverse side, and a plurality of discrete actuators engaging the reverse side and arranged in a selected pattern to control the surface shape as individual discrete activators are activated. It is preferred that the actuators have multiple discrete stable states of elongation. A particularly preferred embodiment uses actuators that are binary with two stable states of elongation.

Abstract: The system of the present invention includes an actuator having at least two electrodes, an elastomeric dielectric film disposed between the two electrodes, and a frame attached to the elastomeric dielectric film. The frame provides a linear actuation force characteristic over a displacement range. The displacement range is preferably the stroke of the actuator. The displacement range can be about 5 mm and greater. Further, the frame can include a plurality of configurations, for example, at least a rigid members coupled to a flexible member wherein the frame provides an elastic restoring force. In preferred embodiments, the rigid member can be, but is not limited to, curved beams, parallel beams, rods and plates. In a preferred embodiment the actuator can further include a passive element disposed between two flexible members such as, for example, links to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element.

Abstract: The present invention is directed to devices and systems used in magnetic imaging environments that include an actuator device having an elastomeric dielectric film with at least two electrodes, and a frame attached to the actuator device. The frame can have a plurality of configurations including, such as, for example, at least two members that can be, but not limited to, curved beams, rods, plates, or parallel beams. These rigid members can be coupled to flexible members such as, for example, links wherein the frame provides an elastic restoring force. The frame preferably provides a linear actuation force characteristic over a displacement range. The linear actuation force characteristic is defined as ±20% and preferably 10% over a displacement range. The actuator further includes a passive element disposed between the flexible members to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element.

Abstract: The system of the present invention includes an actuator having at least two electrodes, an elastomeric dielectric film disposed between the two electrodes, and a frame attached to the elastomeric dielectric film. The frame provides a linear actuation force characteristic over a displacement range. The displacement range is preferably the stroke of the actuator. The displacement range can be about 5 mm and greater. Further, the frame can include a plurality of configurations, for example, at least a rigid members coupled to a flexible member wherein the frame provides an elastic restoring force. In preferred embodiments, the rigid member can be, but is not limited to, curved beams, parallel beams, rods and plates.

Abstract: The present invention is directed to devices and systems used in magnetic imaging environments that include an actuator device having an elastomeric dielectric film with at least two electrodes, and a frame attached to the actuator device. The frame can have a plurality of configurations including, such as, for example, at least two members that can be, but not limited to, curved beams, rods, plates, or parallel beams. These rigid members can be coupled to flexible members such as, for example, links wherein the frame provides an elastic restoring force. The frame preferably provides a linear actuation force characteristic over a displacement range. The linear actuation force characteristic is defined as ±20% and preferably 10% over a displacement range. The actuator further includes a passive element disposed between the flexible members to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element.

Abstract: A wheel base or mobile platform providing omnidirectional motion and control. At least two offset wheel assemblies are coupled to a platform that supports a load. Each offset wheel assembly has two wheels that share a common axis and a mechanical link that is pivotally coupled to a pivot point on the rigid platform and supports the two wheels in such a manner that the common axis is displaced from the pivot point. The common axis of the wheels is free to rotate about an axis parallel to the planes of rotation of the wheels. The platform may be turned in any direction specified by a user from any instantaneous configuration or velocity in accordance with a method uniquely specifying a torque to be applied to each of the wheels while each of the wheels is in rolling motion.

Abstract: An elegant, cost-effective apparatus and method is disclosed for compensating the effect of joint friction in manipuulators. The invention uses a six axis wrench sensor (also called a force/torque sensor) mounted between the manipulator and a reference body upon which it is supported. From the base wrench measurements, for rotary joints, the joint torques are estimated. The estimation apparatus uses Newton-Euler relations of successive link bodies. The estimated torque is fed back through a torque controller, that virtually eliminates friction and gravity effects. A position control loop encloses the torque controller and provides it with desired torques computed from measured position errors. For linear joints, appropriate forces are estimated. Coupled to link position sensors and the wrench sensor, is a gravity compensator, which generates a dynamic wrench signal that corresponds to the gravity compensated dynamic component of the base wrench signal, based on the position signals and the base wrench signal.