Abstract: Embodiments of a solid propellant rocket motor are provided. In one embodiment, the solid propellant rocket motor includes a pressure vessel having a cavity therein, a solid propellant disposed within the cavity, a nozzle fluidly coupled to the cavity, and a tungsten alloy burst disc positioned proximate the nozzle. The tungsten alloy burst disc is configured to block gas flow through the nozzle when the tungsten alloy burst disc is intact and to fragment at a predetermined burst pressure. Embodiments of a method are further provided for manufacturing a burst disc. In one embodiment, the method comprises the step of forming a burst disc from a tungsten alloy. Embodiments of a burst disc are still further provided. In one embodiment, the burst disc includes an outer annular portion, and a central portion comprising a tungsten alloy.

Abstract: Embodiments of a solid propellant rocket motor are provided. In one embodiment, the solid propellant rocket motor includes a pressure vessel having a cavity therein, a solid propellant disposed within the cavity, a nozzle fluidly coupled to the cavity, and a tungsten alloy burst disc positioned proximate the nozzle. The tungsten alloy burst disc is configured to block gas flow through the nozzle when the tungsten alloy burst disc is intact and to fragment at a predetermined burst pressure. Embodiments of a method are further provided for manufacturing a burst disc. In one embodiment, the method comprises the step of forming a burst disc from a tungsten alloy. Embodiments of a burst disc are still further provided. In one embodiment, the burst disc includes an outer annular portion, and a central portion comprising a tungsten alloy.

Abstract: A method of and apparatus for providing self-learning correction to the error in positioning movement of a platform in a vehicular wheelchair lift or any moving member of machinery or an equipment. The method includes the steps of programming the platform or moving member to stop at a target position, calculating an error between the programmed target position and an actual stop position of the platform or moving member, and deriving a new target position to stop the platform or moving member based on the calculated error to compensate the overshoot or shortcoming of the actual stop position of the platform or moving member. The apparatus implementing this method may include a programmable control mechanism such as a microprocessor having means for performing the programmed sequential operations.

Abstract: A threshold warning system is installed directly on a conventional lift to fully comply with the SAE standard No. J2093. The threshold warning system comprises a sensor device for sensing whether there is an object crossing the boundary of the threshold zone, and a platform position indication device for determining whether the platform is in an unsafe position. The threshold warning system comprises an audible and/or visual warning device for warning a wheelchair user or a passenger when the user or passenger moves into a threshold zone from the vehicle opening while the platform is in an unsafe level for exiting from or boarding into the vehicle.