Abstract: A method for fore-aft stabilization of a vehicle for motion in a specified direction over an underlying surface. The vehicle has at least one forward wheel and at least one aft wheel, and the forward wheel is characterized by a force normal to the instantaneous direction of motion of the vehicle. A motor actuator drives each aft wheel, and a controller governs the motor actuator or motor actuators in such a manner as to dynamically stabilize the vehicle, according to a uniform control law, when the forward wheel is in contact with the underlying surface or not. A torque is applied to the aft wheel on the basis of vehicle pitch or the force on the forward wheel normal to the direction of motion. Additionally, a periodic rotational modulation may be applied to the aft wheel, and a stabilizing torque provided based on a detected response, either of vehicle pitch or of normal force on the front wheel.

Abstract: Methods and apparatus for detecting a sensor angle error in a system in which a measured quantity is determined on the basis of a phase of a signal. A signal derived from the measurement of multiple sensors is ascribed to a vector in a two-dimensional space, and a norm is calculated characterizing that vector. A value is calculated characterizing variation of that norm over a specified period of time and that value is compared with a threshold in order to identify a sensor fault.

Abstract: An electric device includes a motor and a motor drive for commanding a torque generated by the motor. A fault control circuit detects a fault condition associated with the motor drive. Upon detection of the fault condition, the fault control circuit adjusts the torque commanded by the motor drive.

Abstract: An electric device includes a motor and a motor drive for commanding a torque generated by the motor. A fault control circuit detects a fault condition associated with the motor drive. Upon detection of the fault condition, the fault control circuit adjusts the torque commanded by the motor drive.

Abstract: A class of transporters for carrying an individual over ground having a surface that may be irregular. Various embodiments have a motorized drive, mounted to the ground-contacting module that causes operation of the transporter in an operating position that is unstable with respect to tipping when the motorized drive arrangement is not powered. Related methods are provided for determining the maximum operating speed of the transporter from measurement of battery parameters and transporter motor current and for limiting the speed of the transporter to maintain stability.

Abstract: A class of transporters for carrying an individual over ground having a surface that may be irregular. Various embodiments have a motorized drive, mounted to the ground-contacting module that causes operation of the transporter in an operating position that is unstable with respect to tipping when the motorized drive arrangement is not powered. Related methods are provided for determining the maximum operating speed of the transporter from measurement of battery parameters and transporter motor current and for limiting the speed of the transporter to maintain stability based on various sets of operationally imposed margins.

Abstract: A device and method for equalizing the charge among a plurality of batteries redundantly driving a motor. The batteries are coupled to the motor through isolated windings and to each other through the drive shaft. The device senses the charge of the batteries and then controls the current from each of the batteries to its respective winding to equalize the charge. Related methods are provided to maximize the speed limit of a balancing transporter.

Abstract: A device and method for providing yaw control for a balancing transporter that has two laterally disposed ground-contacting wheels. The method has the steps of receiving a user input of a desired yaw value; comparing an instantaneous yaw value with the desired yaw value to generate a yaw error value; processing the yaw error value to obtain a yaw command signal; and applying the yaw command signal in conjunction with a pitch command signal based on a pitch error in such a manner as to maintain balance of the transporter in the course of executing yaw control. The yaw command signal may include component terms quadratic in the pitch error and/or a function of a common wheel rotational velocity. A control input mechanism is wirelessly coupled to the controller of the balancing transporter so as to maintain the sealed integrity of a user interface.

Abstract: A class of transporters for carrying an individual over ground having a surface that may be irregular. Various embodiments have a motorized drive, mounted to the ground-contacting module that causes operation of the transporter in an operating position that is unstable with respect to tipping when the motorized drive arrangement is not powered. Related methods are provided for determining the maximum operating speed of the transporter from measurement of battery parameters and transporter motor current and for limiting the speed of the transporter to maintain stability based on various sets of operationally imposed margins.

Abstract: A device and method for equalizing the charge among a plurality of batteries redundantly driving a motor. The batteries are coupled to the motor through isolated windings and to each other through the drive shaft. The device senses the charge of the batteries and then controls the current from each of the batteries to its respective winding to equalize the charge. Related methods are provided to maximize the speed limit of a balancing transporter.

Abstract: A class of transporters for carrying an individual over ground having a surface that may be irregular. Various embodiments have a motorized drive, mounted to the ground-contacting module that causes operation of the transporter in an operating position that is unstable with respect to tipping when the motorized drive arrangement is not powered. Related methods are provided for determining the maximum operating speed of the transporter from measurement of battery parameters and transporter motor current and for limiting the speed of the transporter to maintain stability.

Abstract: An electric device includes a motor and a motor drive for commanding a torque generated by the motor. A fault control circuit detects a fault condition associated with the motor drive. Upon detection of the fault condition, the fault control circuit adjusts the torque commanded by the motor drive.

Abstract: Provided is a force-controlled hydro-elastic actuator, including a hydraulic actuator, having a connection to hydraulic fluid and including a mechanical displacement member positioned to be mechanically displaced by fluid flow at the actuator. A valve is connected at the hydraulic actuator connection and has a port for input and output of fluid to and from the valve. At least one elastic element is provided in series with the mechanical displacement member of the hydraulic actuator and is positioned to deliver, to a load, force generated by the hydraulic actuator. A transducer is positioned to measure a physical parameter indicative of the force delivered by the elastic element and to generate a corresponding transducer signal. A force controller is connected between the transducer and the valve to control the valve, based on the transducer signal, for correspondingly actuating the hydraulic actuator and deflecting the elastic element.

Abstract: Provided is a force-controlled hydro-elastic actuator, including a hydraulic actuator, having a connection to hydraulic fluid and including a mechanical displacement member positioned to be mechanically displaced by fluid flow at the actuator. A valve is connected at the hydraulic actuator connection and has a port for input and output of fluid to and from the valve. At least one elastic element is provided in series with the mechanical displacement member of the hydraulic actuator and is positioned to deliver, to a load, force generated by the hydraulic actuator. A transducer is positioned to measure a physical parameter indicative of the force delivered by the elastic element and to generate a corresponding transducer signal. A force controller is connected between the transducer and the valve to control the valve, based on the transducer signal, for correspondingly actuating the hydraulic actuator and deflecting the elastic element.

Abstract: A movable member mounted in an opening in the back support section of a multisectioned surgical table. The movable member is so pivotally connected to a portion of the perimeter of the opening that the movable member can assume a range of articulated positions relative to the back section for lifting portions of the patient's body. The movable member has contoured edges for providing a smooth, preferably padded surface against which the portions of the patient's body can be supported and restrained against lateral rolling. The edges of the movable member are preferably also contoured to define a perineal cutout. Means are provided for locking the movable member into selective positions within the range of articulated positions.