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K. Zhang et al.
to be impacted by space debris, penetration will cause leakage of gas in the enclosure.
To ensure the safety of astronauts, space debris impact sensing system is proposed.
The sensing system is accompanied by some measurable physical phenomena during
HVI, such as electromagnetic radiation (visible light, infrared light, microwave),
AE wave, plasma, impact acceleration, secondary debris cloud, impact cratering or
perforation damage. Since on-orbit sensing system was put forward, series of related
work were carried out. Many on-orbit sensing methods based on different principles
were designed, including impact acceleration sensing method [1–3], thermal imaging
detection method [4], resistance film sensing method [5], microwave sensing method
[6], PVDF sensor sensing system, etc. Among them, AE technology were attracted
much attention, such as Prosser compared the difference of AE signals between lowvelocity and high-velocity impacts [7], it was concluded that low-velocity impacts
produced signals with little extensional mode and large flexural mode components,
and high-velocity impacts had large extensional mode components. Schäfer used
this technology to locate the impact of space debris on aluminum alloy plate and
honeycomb aluminum plate [8].
Time difference of arrival (TDOA) source location problem has been studied in
isotropic and anisotropic structures [9–12]. For an isotropic plates with the known
wave speed, locating an AE event is traditionally done by trilateration. The triangulation technique works very well when the velocity of the signal in the medium
and the time of arrival of the signal at all three sensor locations are known. Kundu
proved that small variations in the wave speed estimation can significantly alter the
predicted source location. This ambiguity in the source location prediction can be
reduced by increasing the number of receiving sensors [13].
For manned spacecraft, adding protective structure is an effective protective
method. The double-layer aluminum alloy plate structure is a typical protective structure. When the space debris penetrates the front plate, it breaks into many fragmentation called secondary debris cloud. This process reduces the impact energy density
and also reduces the degree of impact damage. But it also brings new problems for
localization. Most of the works focus on single point source localization, the AE
signals of the second debris cloud impact are produced by multiple particles hitting
a certain area in a short time. How to locate this kind of impact is a new problem.
This paper presents a method to locate debris cloud impact events. Simulation of
space debris impact by launching projectile with two-stage light gas gun. The debris
cloud impact damage is an area. By analyzing the motion characteristics of debris
cloud, the damage center is located by TDOA method. The spectrum characteristics of impact signals with different initial velocities are analyzed. The relationship
between AE signals and damage area is analyzed. The characteristic parameter used
to estimate the size of impact damage area is constructed.
K. Zhang et al.
to be impacted by space debris, penetration will cause leakage of gas in the enclosure.
To ensure the safety of astronauts, space debris impact sensing system is proposed.
The sensing system is accompanied by some measurable physical phenomena during
HVI, such as electromagnetic radiation (visible light, infrared light, microwave),
AE wave, plasma, impact acceleration, secondary debris cloud, impact cratering or
perforation damage. Since on-orbit sensing system was put forward, series of related
work were carried out. Many on-orbit sensing methods based on different principles
were designed, including impact acceleration sensing method [1–3], thermal imaging
detection method [4], resistance film sensing method [5], microwave sensing method
[6], PVDF sensor sensing system, etc. Among them, AE technology were attracted
much attention, such as Prosser compared the difference of AE signals between lowvelocity and high-velocity impacts [7], it was concluded that low-velocity impacts
produced signals with little extensional mode and large flexural mode components,
and high-velocity impacts had large extensional mode components. Schäfer used
this technology to locate the impact of space debris on aluminum alloy plate and
honeycomb aluminum plate [8].
Time difference of arrival (TDOA) source location problem has been studied in
isotropic and anisotropic structures [9–12]. For an isotropic plates with the known
wave speed, locating an AE event is traditionally done by trilateration. The triangulation technique works very well when the velocity of the signal in the medium
and the time of arrival of the signal at all three sensor locations are known. Kundu
proved that small variations in the wave speed estimation can significantly alter the
predicted source location. This ambiguity in the source location prediction can be
reduced by increasing the number of receiving sensors [13].
For manned spacecraft, adding protective structure is an effective protective
method. The double-layer aluminum alloy plate structure is a typical protective structure. When the space debris penetrates the front plate, it breaks into many fragmentation called secondary debris cloud. This process reduces the impact energy density
and also reduces the degree of impact damage. But it also brings new problems for
localization. Most of the works focus on single point source localization, the AE
signals of the second debris cloud impact are produced by multiple particles hitting
a certain area in a short time. How to locate this kind of impact is a new problem.
This paper presents a method to locate debris cloud impact events. Simulation of
space debris impact by launching projectile with two-stage light gas gun. The debris
cloud impact damage is an area. By analyzing the motion characteristics of debris
cloud, the damage center is located by TDOA method. The spectrum characteristics of impact signals with different initial velocities are analyzed. The relationship
between AE signals and damage area is analyzed. The characteristic parameter used
to estimate the size of impact damage area is constructed.