Article
Motion Planning of Ground Simulator for Space Instable Target
Based on Energy Saving
Xinlin Bai
1,2,3
, Xiwen Li
1
, Zhen Zhao
4
, Mingyi Yang
2,3
, Zhang Zhang
5
, Zhigang Xu
2,3
, Mingyang Liu
2,3
and Qi Xia
1,
*
Citation: Bai, X.; Li, X.; Zhao, Z.;
Yang, M.; Zhang, Z.; Xu, Z.; Liu, M.;
Xia, Q. Motion Planning of Ground
Simulator for Space Instable Target
Based on Energy Saving. Machines
2021, 9, 368. https://doi.org/
10.3390/machines9120368
Academic Editor: Dario Richiedei
Received: 12 November 2021
Accepted: 15 December 2021
Published: 18 December 2021
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4.0/).
1
School of Mechanical Science and Engineering, Huazhong University of Science and Technology,
Wuhan 430074, China; baixinlin@sia.cn (X.B.); xiwenli@hust.edu.cn (X.L.)
2
Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China;
myyang@sia.cn (M.Y.); zgxu@sia.cn (Z.X.); liumingyang@sia.cn (M.L.)
3
Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110169, China
4
Aerospace System Engineering Shanghai, Shanghai 201109, China; zhaozhen101@163.com
5
Shanghai Aerospace Chemical Engineering Institute, Huzhou 313000, China; zhangzhanghbu@sina.com
* Correspondence: qxia@mail.hust.edu.cn
Abstract:
In order to achieve the high-precision motion trajectory in ground experiment of space
instable target (SIT) while reducing the energy consumption of the motion simulator, a robot motion
planning method based on energy saving is proposed. Observable-based ground robot motion exper-
iment system for SIT is designed and motion planning process is illustrated. Discrete optimization
mathematical model of energy consumption of motion simulator is established. The general motion
form of the robot joints in ground test is given. The optimal joint path of motion simulator based
on energy consumption under discontinuous singularity configuration is solved by constructing
the complete energy consumption directed path and Dijkstra algorithm. An improved method by
adding the global optimization algorithm is used to decouple the coupled robot joints to obtain the
minimum energy consumption path under the continuous singularity configuration of the motion
simulator. Simulations are carried out to verify the proposed solution. The simulation data show that
total energy saving of motion simulator joints adopting the proposed method under the condition of
non-singularity configuration, joints coupled motion with continuous singularity configuration, and
coexistence of non-singularity path and continuous singularity path are, respectively, 72.67%, 28.24%,
and 62.23%, which proves that the proposed method can meet the requirements of ground motion
simulation for SIT and effectively save energy.
Keywords:
space instable target; robot motion planning; energy saving; optimal joint path; continu-
ous singularity configuration; ground experiment
1. Introduction
As unstable targets in space continue to increase and become more threatening, ma-
neuvering tasks, such as on-orbit removal, have become more and more urgent [
1
–
4
]. Space
instable targets are objects to be manipulated in orbit, such as satellites and space debris, in
space operation missions. The movement of SIT is complicated, and their manipulation
task is also difficult [
5
]. In order to verify the feasibility of the space control method and
optimize the control algorithm, it is necessary to conduct ground manipulation simulation
experiments of SIT [
6
,
7
]. The primary task of the ground simulation test is to accurately
simulate the relative spatial movement and relative attitude motion between SIT and space
operation aircraft.
A serial robot with multi-DOF, widely used in areas such as grinding, polishing, and
parts processing, has the advantages of a large range of pose motion and high repeat
positioning accuracy. It is an effective method to achieve the given motion of SIT in ground
test platform through using six-DOF industrial robot [
8
,
9
]. During simulating given space
Machines 2021, 9, 368. https://doi.org/10.3390/machines9120368 https://www.mdpi.com/journal/machines
