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4 Structure and Mechanism Technology of Lunar Lander
(a) Before landing
(b) After landing
Fig. 4.8 Luna 21 of Soviet Union
Fig. 4.9 Deployment of
Sojourner
It shows that the types and functions of mechanisms are significantly different
due to significant differences of the characteristics of the mission and the general
configuration for lunar and Mars landers that has been launched. For the lunar lander,
the design of the mechanism shall meet the specific mission requirements of the lunar
lander. Special attention shall be paid in design of lunar lander mechanisms as follows
[12]:
(1) Lightweight. The requirement is the same as the structure.
(2) For the mechanism unlocked and deployed during orbital flight, it is difficult to
endure landing impact load if it is not folded before landing. The load during
orbit maneuver and powered descent shall not be ignored.
(3) Lunar dust environment. Before landing, the plume of engine will activate lunar
dust. When landing, the landing cushion mechanism will also activate lunar
dust. It will affect the normal movement of mechanisms if lunar dust enters
into the motion join.