Lunar ascent control using explicit guidance and slidng mode techniques

Ascent guidance and control techniques are vital for the lunar lander and the upcoming extensive lunar explorations. To improve the efficiency and robustness of the ascent controller, an explicit guidance and integral sliding model approach are synthesized in this paper. In the design of the guidance law, model simplification is adopted and analytic solutions replace the traditional iteration process. The efficiency is improved without loss of orbit insertion accuracy. For the controller design, by setting the initial value of the integral function and designing of the reaching law, the response speed is accelerated and finite-time stability is guaranteed. Simulations are conducted and performances are verified in the presence of parameter uncertainties.