摘要
月球车是实现月面巡视探测的关键运载工具,必须具有扩展科学探测范围以及携带有效载荷的功能。月球表面地形复杂,环境恶劣,加上属于远程无人驾驶移动平台,因此高移动性能是月球车移动系统的核心技术。
本论文研究了主动摆臂四轮菱形月球车移动系统(FWRA),对其移动性能进行了详细分析。具体如下：
(1)对FWRA的结构特点和设计思路进行了分析,并研制了其物理样机。为了增强月球车的越障性能和转向性能,该移动系统采用了主被动摆臂机构和偏置转向机构。主被动摆臂机构具有很强的被动路面适应性和主动调整功能,与偏置转向机构结合,可以大大提高月球车的移动性能。
(2)提出了移动系统越障性能的量化分析方法。该方法主要是根据移动系统在越障过程中需要的附着系数的大小来判断其越障性能的好坏。利用该方法,建立了FWRA移动系统越障过程的力学方程,利用该方程分析了FWRA移动系统的越障性能。考虑到主动摆臂的自我调节功能,将各摆臂摆角对FWRA移动系统越障性能的影响进行了分析。将移动系统转向时最小干涉范围作为判断月球车移动系统转向性能的判断准则,利用该准则研究了转向机构对FWRA移动系统转向性能的影响。利用移动系统越障性能和转向性能的判断准则,将FWRA移动系统与主副摇臂六轮月球车移动系统在越野性和转向机动性能等方面进行了比较,结果表明FWRA移动系统具有很好的移动性能。
(3)提出了新的刚性车轮在松软路面行驶的动力学建模方法。该方法对车轮进行了离散化处理,并基于沉陷理论和剪切理论计算轮壤接触表面的应力分布,从而可以预测车轮的挂钩牵引力以及转矩。利用该方法建立了光滑刚性轮和有齿刚性轮在松软路面行驶的动力学模型,并将该模型整合到整车动力学模型中,对刚性轮在松软地面行驶时的挂钩牵引力和驱动力矩进行了仿真计算。将仿真结果与试验结果进行比较,结果表明本论文提出的轮壤接触算法可以很好的模拟刚性轮与松软路面接触时的力学状态,从而证明该轮壤动力学模型具有较高的可信度。
(4)利用新的轮壤建模方法,将车轮与松软路面作用的子模型整合到主副摇臂六轮月球车移动系统动力学模型中,建立了主副摇臂六轮月球车移动系统在松软路面行驶的动力学模型。通过仿真,对车轮表面的应力分布以及电机转矩进行了分析。为验证模型的正确性,开发了信号处理模块和整车试验平台,并对主副摇臂六轮月球车移动系统在松软沙地进行了试验研究。将仿真和试验中的车轮功耗以及滑移率进行了比较,结果表明该模型具有很好的可信性,可以利用此轮壤接触方法建立多轮多轴移动系统在松软路面行驶的动力学模型。
(5)根据本论文提出的轮壤接触算法建立了FWRA移动系统在月壤表面行驶的动力学模型。利用该模型对FWRA移动系统在月面环境下的越障性能进行了预估,并研究了主动摆臂对FWRA移动系统越障性能的影响,结果表明摆臂机构对提高FWRA移动系统在月表环境下的越障能力具有重要作用。另外,利用该模型对FWRA移动系统的爬坡过程和爬坡性能进行了仿真分析。从对FWRA移动系统越障和爬坡性能的分析可以看出,该模型可以很好的预测FWRA移动系统在月面行驶时的移动性能。
The lunar exploration tasks require that the mobility system of a lunar rover must have the capability to carry up the payload for large-area and long-term exploration. The environment of the lunar surface is severe and unpredictable such that the high mobility performance is the key technique for the mobility system.
The mobility performance of the four-wheel-rhombus-arranged mobility system (FWRA) of a new concept lunar rover is investigated and some new modeling methodologies are developed in this dissertation. The main works are summarized as follows:
(1) The structure properties of the four-wheel-rhombus-arranged (FWRA) mobility system are analyzed and the physical prototype is developed. In order to possess the characteristic of high obstacle-climbing capability and turning maneuverability, the mobility system integrates the indepENDent active suspension with the passive rotary link structure and is equipped with the offset steering mechanism. The active suspension with swing arms improves the rover's capacity to escape from trapped environment and the passive rotary link structure guarantees the continuous contact between the four wheels and the terrain. Using the suspensions and the offset steering mechanism, the off-road performance of FWRA mobility system can be improved considerably.
(2) In order to investigate the obstacle-crossing capability, the mechanical judging method is put forward based on quasi-static theory. The obstacle-crossing capability can be judged by the road adhesive coefficient in this method. According to this method, the quasi-static equations of the FWRA mobility system are developed to compute the road adhesive coefficient while the wheels cross the dIFferent obstacles. THEN, the obstacle-climbing capability of FWRA mobility system is analyzed. Due to the adjustable property of the swing arms, the influence of swing arms on the climbing-capability is studied. Besides, the minimum value of the turning radial is considered to be the judging criterion on turning quality. The influence of the steering mechanism on the turning performance of the mobility system is investigated according to this criterion. In comparison with a six-wheel rocker-bogie mobility system in theory, the FWRA mobility system shows the higher mobility performance.
(3) A new modeling method for dynamic interactive behavior of rigid wheel traveling on the loose soil is put forward. Using this method, the surface and grousers of the wheel are both divided into finite elements. According to the sinkage-pressure theory and Jacce theory, the forces acting at the elements are discrete and computed separately. Thus, the distribution of the normal and shear stresses at the interface between wheel and soil can be analyzed and the drawbar pull and torque of the wheel can be predicted. In order to validate this model, the virtual simulation is developed to study the drawbar pull and the torque of the wheel. The analytical comparison between the predicted values and the measured values indicates that this modeling method has the capability to predict the performance of the wheels traveling on the loose soil with high accuracy.
(4) Based on the new modeling method, the wheel-soil contact model is integrated into the six-wheel six-wheel rocker-bogie mobility system. The dynamical model of the six-wheel rocker-bogie mobility system is developed to investigate the off-road mobility performance while the rover travels on the loose soil. Using this model, the distribution of the stress acting on the interface between the wheel and soil and the drawbar pull and torque of the wheel can be predicted. In order to validate this model, the test bed and the physical prototype of the six-wheel rocker-bogie mobility system are both developed. The accuracy and reliability of the model are verIFied by some experiments. The comparison between the measured results and the simulation results indicates that this model can be used to investigate the performance of the multi-wheel rover traveling on the loose soil.
(5) The dynamical model of the FWRA mobility system traveling on the lunar surface is developed. Using this model, the correlations between the wheels of FWRA mobility system are analyzed. The obstacle-crossing capability and the grade-climbing ability are predicted while the FWRA mobility system travels on the lunar surface. The influence of swing-arms on the mobility capability is investigated. The results indicate that the swing arms can greatly improve the obstacle-crosing and grade-climbing capability. From the previous analysis, it can be seen that this dynamical model is useful to investigate the performance of the FWRA mobility system traveling on the lunar surface.
引文
[1]Takashi K, Yoji K, Yasuharu K, et al. Small, Light-Weight Rover "Micro5" for Lunar Exploration, Acta Astronautica,2003,52:447-453
[2]Laurence B, Iares L. A Ground Demonstrator of Planetary Rover Technologies. Robotics and Autonomous Systems,1998,23:89-97
[3]Okada T, Sasaki S, Sugihara T, et al. Lander and Rover Exploration on the Lunar Surface:A Study for SELENE-B Mission. Advances in Space Research,2006,37: 88-92
[4]http://news.sohu.com/20071026/n252871588.shtml,2007-10-26
[5]http://news.xinhuanet.com/tech/2010-04/16/content_13364909.htm,2010-04-16
[6]Bernard H F, Pascale E. Journey to the Moon:Recent Results, Science,Future Robotic and Human Exploration. Advances in Space Research,2008,42:235-237
[7]Yongchun Z, Ziyuan O, Chunlai L, et al. China's Lunar Exploration Program:Present and Future. Planetary and Space Science,2008,56:881-886
[8]欧阳自远.中国探月行动.科学前沿,1993,97
[9]梁斌,王巍,王存恩.开发我国月球车的初步设想.国际太空,2003,2：23-25
[10]Shigeo H, Naritoshi O, Takaya S, et al. Fundamental Considerations for the Design of a Planetary Rover. Proc.of ICRA, Nagoya,1995,1939-1944
[11]Shigeo H, Hiroyuki K, Yasufumi W, Nobuto Y. Mobility and Remote Control Schemes of an Offset-Wheel Rover Vehicle. Proc. Int. Conf. On Mobile Planetary Robots & Rover Roundup.1997,12-20
[12]Shigeo H, Hiroyuki K, Yasufumi W, et al. The Mobility Design Cocepts/ Characteristics & Ground Testing of an Offset-Wheel Rover Vehicle, Proc. Int. Conf. On Mobile Planetary Robots & Rover Roundup.1997,1-11
[13]David W, Maria B, Daniel C, et al. Operating Nomad during the Atacama Desert Trek. SST Int. Report,1998,83-87
[14]Rollins E, Luntz J, Foessel A, et al. Nomad:A Demonstration of the Transforming Chassis. Proceedings of ICRA 98,1998,137-144
[15]Yutaka K, Haruaki I, Yoshisada T. The Selene Project and the Following Lunar Mission. Acta Astronautica,2000,47 (2-9):467-473
[16]Mike W, Bob J, Saverio M. A Brief History of the Lunar Roving Vehicl,2002,5-20.
[17]http://marsrovers.jpl.nasa.gov/home/index.html,2004-3-10
[18]http://www.marstoday.com/news/viewsr.html?pid=18352,2001-04-25
[19]江磊,姚其昌,何亚丽,张学明,韩宇石.星球车行走系统和他的研制者们-俄罗斯篇.机器人技术与应用,2008,3：17-19
[20]Krotkov E, Bares J, Katragadda L, et al. Lunar Rover Technology Demonstrations with Dante and Ratler. In Proc. Intl. Symp. Artl FicialIntelligence, Robotics and Automation for Space, Jet Propulsion Laboratory, Pasadena, CalIFornia,1994, 138-167
[21]http://www.plantary.org/rrgtm/tpr-rover-rus.html,2008-07-24
[22]http://www.cnfxj.org/Html/kepuzhishi/2010-10/3/010209587.html,2010-10-03
[23]Sachiko W, Hitoshi S, Shin-Ichiro N, et al. Design and Mobility Evaluation of Tracked Lunar Vehicle. Journal of Terramechanics,2009,46:105-114
[24]http://www.olog.cn/acticlehtm/78D 1462D57599823ABB.html,2006-11-15
[25]http://www.sh.xinmin.cn/shizheng/2008/04/241127233.html,2008-04-20
[26]李春明,苏波,江磊,卢国轩.面向行驶安全性的月球车车行走系统FDTM,总体设计.机器人技术与应用,2008,3：10-13
[27]Baichao C, Rongben W, Yang J, et al. Design of a High Performance Suspension for Lunar Rover Based on Evolution. Acta Astronautica,2009,66:925-934
[28]陈世荣.摇杆-转向架式月球车月面通过性能研究.[中国科学技术大学博士论文].合肥：中国科学技术大学,2009
[29]http://marsrovers.jpl.nasa.gov/home/index.html,2004-3-10
[30]Carrier et al. Lunar Sourcebook 1991,529
[31]Lunar Surface Models. NASA SP-8023
[32]郑永春.模拟月壤研制与月壤的微波辐射特性研究.[中国科学院博士学位论文].北京：中国科学院,2005
[33]Olhoeft G R, MENDell W. Physical Properties of the Lunarsurface. Lunar Source Book. Cambridge University Press, Cambridge (Chapter 9),1991,78-89
[34]Hambleton J P, Drescher A. Modeling Wheel-Induced Rutting in Soils:Indentation. Journal of Terramechanics,2008,45:201-211
[35]Hambleton J P, Drescher A. Modeling Wheel-Induced Rutting in Soils:Rolling. Journal of Terramechanics,2009,46:35-47
[36]Lav R K, Salokhe V M, Jayasuriya H P W, et al. Experimental Validation of Distinct Element Simulation for Dynamic Wheel-Soil Interaction. Journal of Terramechanics. 1998,35:119-135
[37]邹猛,李建桥,李因武等.刚性轮-月壤相互作用预测模型及试验研究.农业丁程学报,2007,23(12)：119-123
[38]Nakashima H, Fujii H, Oida A, et al. Parametric Analysis of Lugged Wheel Performance for a Lunar Micro-Rover by means of DEM. Journal of Terramechanics, 2007,44:153-162.
[39]Bekker M G. Theory of Land Locomotion. The University of Michigan Press, Ann Arbor,1956,187-231
[40]Wong J Y. Terramechanics and Off-road Vehicles,ELSEvier Amsterdam,1989, 289-302.
[41]Wong J Y, Reece A R. Prediction of Rigid Wheel Performance based on the Analysis of Soil-Wheel Stresses, Part I. Performance of Driven Rigid Wheels. Journal of Terramechanics.1967,4 (1):81-98
[42]Wong J Y, Reece A R. Prediction of Rigid Wheel Performance Based on the Analysis of Soil-Wheel Stresses, part II. Performance of Towed Rigid Wheels. Journal of Terramechanics,1967,4 (2):7-25
[43]Ishigami G, Miwa A, Yoshida K. Steering Trajectory Analysis of Planetary Exploration Rovers based on All-Wheel Dynamics Model. Proc of The International Symposium on ArtlFicial Intelligence Robotics and Automation in space,2005, 56-87
[44]Ishigami G, Miwa A, Nagatani K, et al. Terramechanics-Based Model for Steering Maneuver of Planetary Exploration Rovers on Loose Soil. Journal of Field Robotics, 2007,24 (3):233-250
[45]黄真,赵永生,赵铁石.高等空间机构学.北京：高等教育出版社,2006,49-60
[46]于靖军.机器人机构学数学基础.北京：机械工业出版社,2001,89-102
[47]孙世基,黄承绪.机械系统刚柔耦合动力分析及仿真.北京：人民交通出版社,2000,23-59
[48]Olhoeft G R, MENDell W. Physical Properties of the Lunarsurface. Lunar Source Book. Cambridge University Press, Cambridge (Chapter 9),1991,78-89
[49]Goldich S S. Lunar and Terrestrial Ilmenite Basalt. Science 171,1971,1245-1246
[50]邓宗全,高海波,王少纯等.月球探测车移动系统的关键技术分析.哈尔滨工
[51]业大学学报,2003,35(7)：795-798
[52]李海滨,周家龙,段志信.基于摇臂-转向架结构月球车的越障能力判断准则.力学季刊,2007,28(2)：228-233
[53]孙刚,高峰,孙鹏.可变直径轮月球探测车及其越障能力分析.机械设计,2008,25(5),21-23
[54]余志生.汽车理论(第5版).北京：机械工业出版社,2005,173-225
[55]Bekker M. Introduction to Terrain Vehicle Systems. The University of Michigan Press,1969,59-70
[56]Bekker M. Theory of Land Locomotion. The University of Michigan Press,1960, 165-178
[57]Reina G, Ojeda L, Millela A, et al. Wheel Slippage and Sinkage Detaction for Planetary Rovers. Transactions on Mmechatronics,2006,11 (2):185-195
[58]http//:www.maxonmotor.com.cn,2004-5-18
[59]刘聚德.车辆沙地行驶理论.北京：机械工业出版社,1996,49-68
[60]陈秉聪.土壤-车辆系统力学.北京：中国农业机械出版社,1981,93-125
[61]李建桥,邹猛,贾阳.月球车轮与月壤相互作用动力学模拟.农业机械学报.2008,39(4)：1-5
[62]Ding L, Gao H B, et al. Slip Ratio for Lugged Wheel of Planetary Rover in Deformable Soil:Definition and Estimation. The 2009 IEEE/RSJ International Conference on Intelligent Robots and System. St.Louis, USA,2009,158-166
[63]丁亮,高海波,邓宗全等.基于应力分布的月球车轮地相互作用地面力学模型.机械工程学报,2009,45(7)：49-55
[64]Ding L, Gao H B. Parameter IdentIFication for Planetary Soil Based on a Decoupled Analytical Wheel-Soil Interaction Terramechanics Model. The 2009 IEEE/RSJ International Conference on Intelligent Robots and System. St.Louis, USA,2009, 232-238
[65]Shibly H, Iagnemma K, Dubowsky S. An Equivalent Soil Mechanics Formulation for Rigid Wheels in Deformable Terrain, with Application to Planetary Exploration Rovers. Journal of Terramechanics,2005,42:1-13
[66]Wong J Y, Radforth J R, Preston-thomas J. Some Further Studies of the Mechanical Properties of Muskeg. Journal of Terramechanics,1982,19 (2):48-66
[67]Wong J Y, Garber M, Radforth J R, et al. Characterization of the Mechanical Properties of Muskeg with Special Reference to Vehicle Mobility. Journal of Terramechanics,1979,16 (4):16-29
[68]Robert B, Winnie L, Tim B. Experimental and Simulation Results of Wheel-Soil Interaction for Planetary Rovers. In Proceedings IROS,2005,254-263
[69]Wong J Y, Radforth J R, Preston-thomas J. Some Further Studies of the Mechanical Properties of Muskeg. Journal of Terramechanics,1982,19 (2):48-66
[70]Wong J Y, Garber M, Radforth J R, et al. Characterization of the Mechanical Properties of Muskeg with Special Reference to Vehicle Mobility. Journal of Terramechanics,1979,16 (4):16-29
[71]Robert B, Winnie L, Tim B. Experimental and Simulation Results of Wheel-Soil Interaction for Planetary Rovers. In Proceedings IROS,2005,254-263
[72]Wong J Y, Garber M, Preston T. Theoretical Prediction and Experimental Substantiation of the Ground Pressure Distribution and Tractive Performance of Tracked Vehicle. In Proc. Institution of Mechanical Engineers, Part D, Transport Engineering,1984,198-215
[73]Wong J Y, Asnani V M. Study of the Correlation Between the Performances of Lunar Vehicle Wheels Predicted by the Nepean Wheeled Vehicle Performance Model and Test Data. Proc. IMechE Vol.222 Prt:J.Automobile Engineering,2008,1939-1954
[74]Abd El-Gawwada K A, Croll D A, Soliman F M. El-Sayed. Off-road Tyre Modelling III:Effect of Angled Lugs on Tyre Performance. Journal of Terramechanics.1999,66: 63-75
[75]Yanjin Y, Shichao F, shuhong X. Comparison and Application of Two Models for Wheel-Soil Interaction Simulation. Spacecraft Environment Engineering,2009,26: 206-209
[76]Watyotha C, Gee-Clough D, Salokhe V M. Effect of Circumferential Angle, Lug Spacing and Slip on Lug Wheel Forces. Journal of Terramechanics,2001,38:1-14
[77]赵明华.土力学与基础工程106-120,武汉：武汉工业大学出版社,106-120
[78]赵旗,徐颖,李杰.车辆行驶工况下的沙漠沙本构特性模型的建立.吉林大学学报(工学版).2003,33(1)：42-45
[79]弓永涛,高峰,李雯.刚性车轮月面牵引通过性的模型试验.北京航空航天大学学报,2009,35(5)：649-652
[80]Ding L, Gao H B. Parameter IdentIFication for Planetary Soil Based on a Decoupled Analytical Wheel-Soil Interaction Terramechanics Model. The 2009 IEEE/RSJ International Conference on Intelligent Robots and System. St.Louis, USA,2009, 232-238
[81]Yanjin Y, Shichao F, shuhong X. Comparison and Application of Two Models for Wheel-Soil Interaction Simulation. Spacecraft Environment Engineering,2009,26: 206-209
[82]弓永涛,高峰,李雯.刚性车轮月面牵引通过性的模型试验.北京航空航天大学学报,2009,35(5)：649-652
[83]Ishigami G, Miwa A, Nagatani K, et al. Terramechanics-Based Model for Steering Maneuver of Planetary Exploration Rovers on Loose Soil. Journal of Field Robotics, 2007,24 (3):233-250
[84]Thueer T, Krebs A, Lamon P, et al. Performance Comparison of Rough Terrain Robots Simulation and Hardware. Journal of Field Robotics,2007,18(1):67-82
[85]Kazuya Y, Genya Ishigami. Steering Characteristics of a Rigid Wheel for Exploration on Loose Soil. Proceeding of 2004 IEEE/RSJ International Conference On Intelligent Robots and Systems,2004,3995-4000
[86]张雄,王天舒.计算动力学.北京：清华大学出版社,2007,58-79
[87]洪嘉振.计算多体系统动力学.北京：高等教育出版社,1999,143-190
[88]Shabana A A. Dynamicas of Multi-Body Systems. Combridge University Press,1998, 354-400
[89]孙世基,黄承绪.机械系统刚柔耦合动力分析及仿真.北京：人民交通出版社,2000,23-59
[90]Shyh-shiaw L, Wen-Hwa C. Three-Dimensional Thermoelastic Contact between Two Pplates with Bolted Joints. Journal of Thermal Stress,1996,19:11-23
[91]赵万友.接触问题的分析方法研究和工程应用.成都：电子科技大学,1999,105-118
[92]SusENDar M, Riginald D A. Hertz Contact Model with Non-linear Damping for Punding Simulation. Earthquake Engneering and Structuer Dynamics,2006,35: 61-82
[93]Lankarani H M, Nikravesh P E. A Contact Force Model with Hysteresis Damping for Impact Analysis of Multi-body Systems. Journal of Mechanical Design,1990,1 (12): 369-376
[94]Gino V. A Fast and Robust GJK Implementation for Collision Detection of Convex Objects. To appear,1999
[95]Matsumoto K, Kamimori N, Takizawa Y. Japanese Lunar Exploration Long-Term Plan. Acta Astronautica,2006,58:68-76
[96]Haym B, Leonhard B. Engineering of Lunar Bases. Acta Astronautica,2008,62: 277-299
[97]Carpick R W, Ogletree D F, Salmeron M A. General Equation for Fitting Contact Area and Friction vs Load Measurements. Journal of Colloid and Interface Science, 1999,211 (2):395-400
[98]Sakai H. Theoretical and Experimental Studies on the Dynamics Properties of Tyre. Part 2:Experimental Investigation of Rubber Friction and Deformation of a Tyre. International Journal of Vehicle Design,1981,2 (2):182-247
[99]Elmer F J. Non-Linear Dynamics of Dry Friction. J. Phys. A:Math. Gen.,1997,30: 6057-6063
[100]Kazuya Y, Genya Ishigami. Steering Characteristics of a Rigid Wheel for
[101]Exploration on Loose Soil. Proceeding of 2004 IEEE/RSJ International Conference On Intelligent Robots and Systems,2004,3995-4000
[102]Matsumoto K, Kamimori N, Takizawa Y. Japanese Lunar Exploration Long-Term Plan. Acta Astronautica,2006,58:68-76
[103]Haym B, Leonhard B. Engineering of Lunar Bases. Acta Astronautica,2008,62: 277-299
[104]赵旗,徐颖,李杰.车辆行驶工况下的沙漠沙本构特性模型的建立.吉林大学学报(工学版).2003,33(1)：42-45
[105]弓永涛,高峰,李雯.刚性车轮月面牵引通过性的模型试验.北京航空航天大学学报,2009,35(5)：649-652