Abstract: A passive prosthetic foot enables a below-knee amputee to walk with near able-body walking motions. The prosthetic foot includes a resilient heel that enables the heel to strike a walking surface more softly than in the prior art and more accurately transition the leg from swing phase to stance phase. The prosthetic foot is modeled generally as a wide Bézier curve, and the foot is characterized according to a set of at least 12 variables, including h, C1d, C2x, C2y, C2d, C3x, C3y, C3d, C4x, C4d, C5d and C6d, where C3y is heel size, C4x is heel geometry and C6d is curve intersection location. The variables are optimized to minimize a difference between a normal lower leg trajectory during gait and a modeled trajectory that includes the prosthetic foot.

Abstract: A high performance, low-cost passive prosthetic knee includes one or more modules to enable able-bodied gait by transfemoral amputees to improve metabolic efficiency and reduce stigma from conspicuous abnormal gaits. A stance stability module includes a latch with a virtual lock axis that automatically locks and unlocks. An early stance flexion module enables able-bodied gait during stance. Hydraulic fluid dampers ensure reliable swing phase control. A swing extension energy storage module stores and returns energy as the knee locks and unlocks, respectively. These modules may be used together, in any combination, or individually.

Abstract: A passive prosthetic foot enables a below-knee amputee to walk with near able-body walking motions. The prosthetic foot includes a resilient heel that enables the heel to strike a walking surface more softly than in the prior art and more accurately transition the leg from swing phase to stance phase. The prosthetic foot is modeled generally as a wide Bézier curve, and the foot is characterized according to a set of at least 12 variables, including h, C1d, C2x, C2y, C2d, C3x, C3y, C3d, C4x, C4d, C5d and C6d, where C3y is heel size, C4x is heel geometry and C6d is curve intersection location. The variables are optimized to minimize a difference between a normal lower leg trajectory during gait and a modeled trajectory that includes the prosthetic foot.

Abstract: A high performance, low-cost passive prosthetic knee includes one or more modules to enable able-bodied gait by transfemoral amputees to improve metabolic efficiency and reduce stigma from conspicuous abnormal gaits. A stance stability module includes a latch with a virtual lock axis that automatically locks and unlocks. An early stance flexion module enables able-bodied gait during stance. Hydraulic fluid dampers ensure reliable swing phase control. A swing extension energy storage module stores and returns energy as the knee locks and unlocks, respectively. These modules may be used together, in any combination, or individually.

Abstract: Described are improved electrodialysis (ED) desalination systems and methods comprising voltage regulation and/or improved stack geometries. The systems and methods provide product water concentrations suitable for drinking (having a total dissolved solids concentration of less than 500 mg/L or 500 ppm) and have a high product recovery ratio.

Abstract: An apparatus for a clutchless manual transmission includes a transmission, a drive shaft, and a motor shaft. The transmission includes an input shaft, an output shaft, and an intermediate gear. The input shaft is coupled to an engine shaft to receive power and the output shaft is coupled to the drive shaft to transmit power to a wheel of a vehicle. The input shaft and output shaft are coupled by a plurality of input and output shaft gears. A first synchronizer is coupled to the output shaft to selectively engage a particular output shaft gear, adjusting the speed of the output shaft relative to the input shaft. The motor shaft receives power from a motor and includes a second synchronizer to selectively engage the engine shaft to the drive shaft via the motor shaft. The apparatus can be used to reduce acceleration and turbo lag in hybrid and high-performance vehicles.

Abstract: Described are improved electrodialysis (ED) desalination systems and methods comprising voltage regulation and/or improved stack geometries. The systems and methods provide product water concentrations suitable for drinking (having a total dissolved solids concentration of less than 500 mg/L or 500 ppm) and have a high product recovery ratio.

Abstract: A manually powered wheelchair includes a first lever associated with a first rear wheel and demountably coupled to a first drivetrain, the first lever having a first brake thereon. The wheelchair also includes a second lever associated with a second rear wheel and demountably coupled to a second drivetrain, the second lever having a second brake thereon. Each drivetrain includes a chainring, a chain, and a freewheel, and each drivetrain has a fixed gear ratio. The freewheel of each drivetrain is actuated by manual pivoting of the lever associated therewith. In use, the wheelchair achieves changes in mechanical advantage when a user shifts the user's hands up and down the first and second levers.

Abstract: A manually powered wheelchair includes a first lever associated with a first rear wheel and demountably coupled to a first drivetrain, the first lever having a first brake thereon. The wheelchair also includes a second lever associated with a second rear wheel and demountably coupled to a second drivetrain, the second lever having a second brake thereon. Each drivetrain includes a chainring, a chain, and a freewheel, and each drivetrain has a fixed gear ratio. The freewheel of each drivetrain is actuated by manual pivoting of the lever associated therewith. In use, the wheelchair achieves changes in mechanical advantage when a user shifts the user's hands up and down the first and second levers.

Abstract: A manually powered wheelchair includes a first lever associated with a first rear wheel and demountably coupled to a first drivetrain, the first lever having a first brake thereon. The wheelchair also includes a second lever associated with a second rear wheel and demountably coupled to a second drivetrain, the second lever having a second brake thereon. Each drivetrain includes a chainring, a chain, and a freewheel, and each drivetrain has a fixed gear ratio. The freewheel of each drivetrain is actuated by manual pivoting of the lever associated therewith. In use, the wheelchair achieves changes in mechanical advantage when a user shifts the user's hands up and down the first and second levers.