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12 Integration and Assembly Technology of Lunar Lander
special. The camera lens was protected with red in AIT. The protection and red alert
cloth for the protrusions should be planned and designed in detail. Before launch,
all ground protection should be confirmed and removed by video record and table
management.
12.5.3 Cable Assembly
The major tasks of spacecraft cable assemblies are cable assembly and connection, which is the typical one in spacecraft system integration and assembly. There
are generally including secondary insulation before cable installation, cable support
and nylon base installation, cable assembly, transition plug bracket and transition
connector installation, cable sorting/binding/fixing, as well as free-end connection,
electrical connector insertion, cable binding/fixing and electrical connector anti-loose
treatment after the cable network test.
The key of spacecraft cable assembly is cable installation. Cable installation is
generally implemented after instrument assembly. At first, the cabin is installed in
single module, and then the cable between modules is connected. There are two
modes of cable installation: The first one is to install the cable in position according
to drawings and documents such as cable installation drawings. The second one is to
manufacture and install the cable with templates. For the second mode, a spacecraft
model is design and manufactured according to actual dimensions, as well as models
of instrument, cable support, and electrical connector brackets, which is installed at
theoretical position of the spacecraft model. According to the technical requirements
of spacecraft design, manufacture and acceptance, the preparation of wire ends, the
manufacture of cables and the welding of wires, cables and electrical connectors are
conducted. After the manufacture is completed, the transplant is conducted. Before
transplant, all electrical connectors are covered with protection caps. When transplanted, all the cables shall be protected from damage. After transplanted, the original
configuration of all the cables shall be maintained. By such method, the cable length
and branches are more accurate, so as to reduce the excessive length and cable mass.
In spacecraft, the cable mass is about 5 ~ 15% of the total mass. The manufacture and
installation of cables with templates will increase the complexity of the development,
but is of great significance in terms of reducing spacecraft mass. In the development
of the Chang’E-3 lunar lander, the cable was designed in form of template cable,
which saved some mass for the lunar lander.
The cable implementation should be implemented according to the technological
requirements.
(1) The low frequency cable was generally installed along the structural surface.
When the cable was installed, the distance between the cable and the instrument, the
fixed spacing and the inner bending radius should be bound according to requirements; When the cable passed through the cavity, corner of the structure or the
instrument, near the high temperature source and the place where the cable was fixed
12 Integration and Assembly Technology of Lunar Lander
special. The camera lens was protected with red in AIT. The protection and red alert
cloth for the protrusions should be planned and designed in detail. Before launch,
all ground protection should be confirmed and removed by video record and table
management.
12.5.3 Cable Assembly
The major tasks of spacecraft cable assemblies are cable assembly and connection, which is the typical one in spacecraft system integration and assembly. There
are generally including secondary insulation before cable installation, cable support
and nylon base installation, cable assembly, transition plug bracket and transition
connector installation, cable sorting/binding/fixing, as well as free-end connection,
electrical connector insertion, cable binding/fixing and electrical connector anti-loose
treatment after the cable network test.
The key of spacecraft cable assembly is cable installation. Cable installation is
generally implemented after instrument assembly. At first, the cabin is installed in
single module, and then the cable between modules is connected. There are two
modes of cable installation: The first one is to install the cable in position according
to drawings and documents such as cable installation drawings. The second one is to
manufacture and install the cable with templates. For the second mode, a spacecraft
model is design and manufactured according to actual dimensions, as well as models
of instrument, cable support, and electrical connector brackets, which is installed at
theoretical position of the spacecraft model. According to the technical requirements
of spacecraft design, manufacture and acceptance, the preparation of wire ends, the
manufacture of cables and the welding of wires, cables and electrical connectors are
conducted. After the manufacture is completed, the transplant is conducted. Before
transplant, all electrical connectors are covered with protection caps. When transplanted, all the cables shall be protected from damage. After transplanted, the original
configuration of all the cables shall be maintained. By such method, the cable length
and branches are more accurate, so as to reduce the excessive length and cable mass.
In spacecraft, the cable mass is about 5 ~ 15% of the total mass. The manufacture and
installation of cables with templates will increase the complexity of the development,
but is of great significance in terms of reducing spacecraft mass. In the development
of the Chang’E-3 lunar lander, the cable was designed in form of template cable,
which saved some mass for the lunar lander.
The cable implementation should be implemented according to the technological
requirements.
(1) The low frequency cable was generally installed along the structural surface.
When the cable was installed, the distance between the cable and the instrument, the
fixed spacing and the inner bending radius should be bound according to requirements; When the cable passed through the cavity, corner of the structure or the
instrument, near the high temperature source and the place where the cable was fixed