The characteristics of asteroids are vital parameters for planning asteroid exploration missions.These characteristics have been explored in close range for some typical asteroids,and are summarized in the article.Thi...The characteristics of asteroids are vital parameters for planning asteroid exploration missions.These characteristics have been explored in close range for some typical asteroids,and are summarized in the article.This allows estimates of the characteristics of asteroid 2016HO_(3),the target of the first Chinese asteroid exploration mission,Tianwen 2.We obtain 80 characteristic parameters in 9 categories and analyze their impacts on the mission.By comparing three close-range exploration modes,we provide advantages and disadvantages of each,and propose suitable methods for the exploration of 2016HO_(3).Owing to the weak gravity and small size of 2016HO_(3),a combination of multiple hovering positions and active orbiting is recommended for scientific exploration.展开更多
As China’s first asteroid exploration mission,the TianWen-2 spacecraft mainly focuses on surface sampling on the near-Earth asteroid 2016 HO3.Different from the usual sampling strategy of releasing a small lander or ...As China’s first asteroid exploration mission,the TianWen-2 spacecraft mainly focuses on surface sampling on the near-Earth asteroid 2016 HO3.Different from the usual sampling strategy of releasing a small lander or ejecting a projectile,the whole TianWen-2 spacecraft will be controlled to achieve touchdown and sampling.However,sampling on a low-gravity regolith-covered surface with unknown physical properties is particularly challenging and risky.In order to successfully implement an in situ exploration,a comprehensive understanding and evaluation of spacecraft dynamics and control behavior during sampling is essential for system design.In this paper,a system-level simulation method for the interaction between the spacecraft and the regolith surface is proposed.The discrete element method is adopted for the simulation of granular material dynamics.Parametric comparisons with test data from microgravity low-speed intrusion drop-tower experiments are implemented to calibrate and verify the physical parameters of the discrete element method simulation model.An explicit multibody dynamics model of the spacecraft is developed to describe dynamic characteristics such as orbit and attitude motion,solar array vibration,and sampler deformation.Finally,numerical simulations of the interaction between granular dynamics,multibody dynamics,and control are performed to study the dynamics and control behaviors of TianWen-2 sampling on an asteroid regolith surface.展开更多
文摘The characteristics of asteroids are vital parameters for planning asteroid exploration missions.These characteristics have been explored in close range for some typical asteroids,and are summarized in the article.This allows estimates of the characteristics of asteroid 2016HO_(3),the target of the first Chinese asteroid exploration mission,Tianwen 2.We obtain 80 characteristic parameters in 9 categories and analyze their impacts on the mission.By comparing three close-range exploration modes,we provide advantages and disadvantages of each,and propose suitable methods for the exploration of 2016HO_(3).Owing to the weak gravity and small size of 2016HO_(3),a combination of multiple hovering positions and active orbiting is recommended for scientific exploration.
基金supported by the National Natural Science Foundation of China(Grant No.U24B2048).
文摘As China’s first asteroid exploration mission,the TianWen-2 spacecraft mainly focuses on surface sampling on the near-Earth asteroid 2016 HO3.Different from the usual sampling strategy of releasing a small lander or ejecting a projectile,the whole TianWen-2 spacecraft will be controlled to achieve touchdown and sampling.However,sampling on a low-gravity regolith-covered surface with unknown physical properties is particularly challenging and risky.In order to successfully implement an in situ exploration,a comprehensive understanding and evaluation of spacecraft dynamics and control behavior during sampling is essential for system design.In this paper,a system-level simulation method for the interaction between the spacecraft and the regolith surface is proposed.The discrete element method is adopted for the simulation of granular material dynamics.Parametric comparisons with test data from microgravity low-speed intrusion drop-tower experiments are implemented to calibrate and verify the physical parameters of the discrete element method simulation model.An explicit multibody dynamics model of the spacecraft is developed to describe dynamic characteristics such as orbit and attitude motion,solar array vibration,and sampler deformation.Finally,numerical simulations of the interaction between granular dynamics,multibody dynamics,and control are performed to study the dynamics and control behaviors of TianWen-2 sampling on an asteroid regolith surface.
