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4 Structure and Mechanism Technology of Lunar Lander
poor. Therefore, in the analysis of force transfer path, it was considered that only
tension and compression load and the in-plane load were transferred by structural
components, and the bending, torque and the out-of-plane load were ignored (unless
the structural component was specially designed to transfer such loads).
The analysis of force transfer path could be conducted after the general configuration, mass property, and configuration of large equipment was determined together
with bearing characteristics of structural components.
For example, the primary structural payload of the Chang’E-3 lunar lander was
launching and the landing impact load. The force transfer path of launching and
landing impact load was analyzed as follows.
1) Transfer of launch load
(1) Lateral load: The transverse load caused by the fuel tanks consisted of upper
and lower parts. The upper load was transferred to the cross support structure
through the rods of fuel tanks and then to the interface ring. The rods of fuel
tanks bore tension and compression, and the cross baffles bear the in-plane
tension, compression and shear load. Pre-embedded beams bore tension and
compression. The lower load was transferred directly to the interface ring. The
load of the lunar rover was transferred to the cross baffle through the bracket.
Most of other equipment was installed on the side and top plates. The load on
the side plates was transferred to the interface ring through the cross support
structure, the top plate and the bottom plate. The cross-support structure, the
top plate and the bottom plate bore in-plane tension and shear loads, while the
pre-embedded beams bore tension and compression. The load on the top plate
was transferred to the interface ring through the top plate and the cross-support
structure. The load on the interface ring was transferred to the launch vehicle.
(2) Longitudinal load: The longitudinal load of the fuel tanks was directly transferred to the interface ring. The longitudinal load of other equipment was transferred to the interface ring through the side plates and the cross support structure. The side plates and the cross support structure bore the in-plane tension
and shear loads. The pre-embedded beams bore tension and compression. The
load on the interface ring was transmitted to the launch vehicle.
From above analysis, it implied that the cross baffles and interface ring were the
major bearing components of the structure for launch load. Special attention should
be paid to the mechanics design of such structure.
2) Transfer of landing impact load
(1) Lateral load: A part of the lateral load was transferred to the cross-support
structure, then to main pillars of landing cushion mechanisms through the
support of landing gears, and to lunar surface through main pillars of landing
gears at last. Another part of the lateral load was transferred to the bottom
plates, then to auxiliary cushion of landing gears, then to main pillars and
finally to lunar surface.
4 Structure and Mechanism Technology of Lunar Lander
poor. Therefore, in the analysis of force transfer path, it was considered that only
tension and compression load and the in-plane load were transferred by structural
components, and the bending, torque and the out-of-plane load were ignored (unless
the structural component was specially designed to transfer such loads).
The analysis of force transfer path could be conducted after the general configuration, mass property, and configuration of large equipment was determined together
with bearing characteristics of structural components.
For example, the primary structural payload of the Chang’E-3 lunar lander was
launching and the landing impact load. The force transfer path of launching and
landing impact load was analyzed as follows.
1) Transfer of launch load
(1) Lateral load: The transverse load caused by the fuel tanks consisted of upper
and lower parts. The upper load was transferred to the cross support structure
through the rods of fuel tanks and then to the interface ring. The rods of fuel
tanks bore tension and compression, and the cross baffles bear the in-plane
tension, compression and shear load. Pre-embedded beams bore tension and
compression. The lower load was transferred directly to the interface ring. The
load of the lunar rover was transferred to the cross baffle through the bracket.
Most of other equipment was installed on the side and top plates. The load on
the side plates was transferred to the interface ring through the cross support
structure, the top plate and the bottom plate. The cross-support structure, the
top plate and the bottom plate bore in-plane tension and shear loads, while the
pre-embedded beams bore tension and compression. The load on the top plate
was transferred to the interface ring through the top plate and the cross-support
structure. The load on the interface ring was transferred to the launch vehicle.
(2) Longitudinal load: The longitudinal load of the fuel tanks was directly transferred to the interface ring. The longitudinal load of other equipment was transferred to the interface ring through the side plates and the cross support structure. The side plates and the cross support structure bore the in-plane tension
and shear loads. The pre-embedded beams bore tension and compression. The
load on the interface ring was transmitted to the launch vehicle.
From above analysis, it implied that the cross baffles and interface ring were the
major bearing components of the structure for launch load. Special attention should
be paid to the mechanics design of such structure.
2) Transfer of landing impact load
(1) Lateral load: A part of the lateral load was transferred to the cross-support
structure, then to main pillars of landing cushion mechanisms through the
support of landing gears, and to lunar surface through main pillars of landing
gears at last. Another part of the lateral load was transferred to the bottom
plates, then to auxiliary cushion of landing gears, then to main pillars and
finally to lunar surface.