Configuration Keeping Technology of Partial Space Elevators

The partial space elevator (PSE) is a space transportation system that consists of one main satellite and one end body connected to a piece of tether. A climber can move along the tether conveying the cargo. This chapter studies a new configure-keeping technology for the stable cargo transportation of the PSE. The new technology contains two control modules. Module I predicts the optimal climber speed as a reference and suppresses the libration motions using the actuators on the climber. The control law of Module I is designed based on an analytical climber speed function, PPC control is used to compensate for system error. Module II further stabilizes the system by eliminating the possible disturbances in real-time acting on the end body. Two control modes are used given to further ensure the system configuration keeping. To test the validity of the proposed technology, two cases are simulated. The numerical results show that the proposed configuration keeping technology is very effective in dealing with the configuration keeping problems for the partial space elevators and other complex nonlinear dynamic systems in the aerospace engineering area.