Abstract: A front-end computing system initializes an instance of a workflow. The workflow contains a plurality of activities. The plurality of activities includes a shim activity. When the front-end computing system executes the workflow instance, the front-end computing system performs the shim activity. When the front-end computing system performs the shim activity, the front-end computing system sends a custom activity assembly to a sandbox computing system. The custom activity assembly is not fully trusted. The sandbox computing system executes the custom activity assembly. The sandbox computing system is isolated from the front-end computing system such that unexpected behavior of the sandbox computing system does not cause the front-end computing system to perform unexpected behavior.

Abstract: A front-end computing system initializes an instance of a workflow. The workflow contains a plurality of activities. The plurality of activities includes a shim activity. When the front-end computing system executes the workflow instance, the front-end computing system performs the shim activity. When the front-end computing system performs the shim activity, the front-end computing system sends a custom activity assembly to a sandbox computing system. The custom activity assembly is not fully trusted. The sandbox computing system executes the custom activity assembly. The sandbox computing system is isolated from the front-end computing system such that unexpected behavior of the sandbox computing system does not cause the front-end computing system to perform unexpected behavior.

Abstract: An improvement in torque control systems for reaction wheel assemblies and the like used primarily for stabilizing space vehicles such as satellites including means for integrating the torque command signal and combining the integrated torque command signal with a feedback signal proportional to the angular speed of the rotor of the reaction wheel assembly thereby producing an error signal proportional to the difference between the integrated torque command signal and the angular speed signal. The error signal is coupled to the rotor spin motor which produces a resultant output torque that has been compensated for disturbance torques and other anomalies whereby the resultant torque applied to the rotor and consequently to the satellite is substantially equal to the commanded torque.