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Spacecraft reaction control systems are used for: attitude control during different stages of a mission; [3] station keeping in orbit; close maneuvering during docking procedures; control of orientation, or "pointing the nose" of the craft; a backup means of deorbiting; ullage motors to prime the fuel system for a main engine burn.
The KTDU-80 system integrates a dual string redundant propellant and pressurization system, a main propulsion system (the SKD), an RCS (the DPO-B) and an attitude control system (the DPO-M). All the propulsion elements are pressure fed rocket engines burning UDMH and N 2 O 4 with a common supply of pressurized propellant. [1]
The R-4D is a small hypergolic rocket engine, originally designed by Marquardt Corporation for use as a reaction control system thruster on vehicles of the Apollo crewed Moon landing program. Aerojet Rocketdyne manufactures and markets modern versions of the R-4D. [1]
A small reaction wheel viewed in profile A momentum/reaction wheel comprising part of a high-accuracy Conical Earth Sensor to maintain a satellite's precise attitude. A reaction wheel (RW) is an electric motor attached to a flywheel, which, when its rotation speed is changed, causes a counter-rotation proportionately through conservation of angular momentum. [1]
In practice, if A and B interconvert with overall rate constants k f and k r, then for most practical purposes, the change in composition becomes negligible after t ~ 3.5/(k f + k r), or approximately five half-lives, and the system product ratio can be regarded as the result of thermodynamic control. In general, short reaction times favour ...
Control engineering is the engineering discipline that focuses on the modeling of a diverse range of dynamic systems (e.g. mechanical systems) and the design of controllers that will cause these systems to behave in the desired manner. Although such controllers need not be electrical, many are and hence control engineering is often viewed as a ...
Chemical reaction engineering aims at studying and optimizing chemical reactions in order to define the best reactor design. Hence, the interactions of flow phenomena, mass transfer, heat transfer, and reaction kinetics are of prime importance in order to relate reactor performance to feed composition and operating conditions.
Its name comes from the information path in the system: process inputs (e.g., voltage applied to an electric motor) have an effect on the process outputs (e.g., speed or torque of the motor), which is measured with sensors and processed by the controller; the result (the control signal) is "fed back" as input to the process, closing the loop.