The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Liang Ding - One of the best experts on this subject based on the ideXlab platform.
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online estimation of terrain parameters and resistance force based on equivalent sinkage for planetary rovers in longitudinal skid
Mechanical Systems and Signal Processing, 2019Co-Authors: Zhen Liu, Liang Ding, Haibo Gao, Junlong Guo, Tianyou Guo, Zongquan DengAbstract:Abstract Wheel-Soil Interaction mechanics plays a crucial role for wheeled mobile robots (WMR) on rough and deformable terrains such as Martian and Lunar surfaces. Skid terramechanics is an essential component for WMRs and generates resistance force when a WMR brakes or on downhill slopes. The basis of classical terramechanics theories for WMRs – Bekker’s normal stress and Janosi’s shear stress equations – are so complex that the wheel-Soil Interaction force/torque equations are not amenable to closed form solutions, which seriously limits the application of terramechanics theories to WMRs. To establish analytical wheel-Soil Interaction expressions, the normal and shear stresses that can be characterized linearly by the proposed terrain stiffness and shear strength, respectively, are presented in this paper. Terrain stiffness and shear strength can be used to characterize terrain mechanical properties. Compared with the experimental data, the maximum relative error of the resistance forces estimated using these expressions at steady state is less than 7%. These validated expressions can be applied to estimate terrain parameters and resistance force online with high accuracy. Terrain’s stiffness and shear strength increase first, and then reach a constant. Before wheels entering steady state, the online estimated resistance force’s relative error is much higher, which can be explained using wheel’s vertical velocity.
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sinkage definition and visual detection for planetary rovers wheels on rough terrain based on wheel Soil Interaction boundary
Robotics and Autonomous Systems, 2017Co-Authors: Haibo Gao, Liang Ding, Baofeng Yuan, Guangjun Liu, Zongquan DengAbstract:Abstract Wheel sinkage detection is of tremendous significance for planetary rover mobility optimization control and prevention of serious wheel sinking. Wheel sinkage is regarded as the distance between the lowest point of the wheel in the Soil and the horizontal flat terrain on relative research. For rovers moving on rough terrains, the above definition is not reasonable because the horizontal flat terrain cannot be found. New wheel sinkage definition and detection method are proposed, based on vision. The sinkage definition rationality is analyzed for various terrain conditions. The discrete mathematical wheel sinkage calculation model, for which the input is acquired through a visual method, is built. Saturation of wheel–Soil Interaction image is adjusted by a dynamic piecewise nonlinear adjustment method The image is processed into a binary image based on HSI (Hue, Saturation, Intensity) color space. The wheel–Soil boundary is extracted from the corrected wheel region outline according to its morphological features. The wheel sinkage and equivalent terrain interface angles are calculated through the discrete mathematical wheel sinkage calculation model. Sinkage definition rationality and detection method applicability are experimentally validated in the four typical terrain conditions (flat, bulgy, sunken, and uneven terrains). Particularly, the experimental results prove the sinkage detection method has high accuracy for flat terrain, for which, the deviation of the sinkage modulus is less than 2% of the wheel radius. The sinkage detection method is proved to have fairly reasonable adaptability to complex illumination conditions, based on the experimental results for different illumination conditions.
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error tolerant switched robust extended kalman filter with application to parameter estimation of wheel Soil Interaction
IEEE Transactions on Control Systems and Technology, 2014Co-Authors: Yuankai Li, Liang DingAbstract:A real-time Soil parameter estimation method for wheel motion control of a planetary rover is proposed. In this method, dominant Soil parameters are updated in real time to compensate the error of the other parameters that are fixed by empirical typical values. Sinkage exponent and internal friction angle are the dominant characteristic parameters of wheel-Soil Interaction, because they dominate the normal stress and sheer stress that constitute the Interaction forces on the contact surface. To estimate these two parameters in real time, a robust extended Kalman filter with error-tolerant switch (ETS-REKF) is proposed in this paper. The developed ETS switches filtering mode between robust and optimal, which is triggered when the magnitude of the sum of system errors reaches a certain threshold that is controlled by an error-tolerant factor (ETF). The proposed filtering algorithm can follow Soil-type change quickly and in the meantime provide smooth parameter estimation without being sensitive to the inherent error of the empirical wheel-Soil Interaction model. From a sufficient condition of the filter stability, the range of the ETF is derived. In addition, a trigonometric approximation method is provided to simplify the original wheel-Soil model for convenient utilization of the filtering algorithm. Simulation and experiment results have demonstrated that the proposed ETS-REKF has the advantages of both optimality of the EKF and robustness of the usual robust EKF, working efficiently in the presence of Soil-type change and inaccuracy of the empirical wheel-Soil model.
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planetary rovers wheel Soil Interaction mechanics new challenges and applications for wheeled mobile robots
Intelligent Service Robotics, 2011Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Keiji Nagatani, Kazuya YoshidaAbstract:With the increasing challenges facing planetary exploration missions and the resultant increase in the performance requirements for planetary rovers, terramechanics (wheel---Soil Interaction mechanics) is playing an important role in the development of these rovers. As an extension of the conventional terramechanics theory for terrestrial vehicles, the terramechanics theory for planetary rovers, which is becoming a new research hotspot, is unique and puts forward many new challenging problems. This paper first discusses the significance of the study of wheel---Soil Interaction mechanics of planetary rovers and summarizes the differences between planetary rovers and terrestrial vehicles and the problems arising thereof. The application of terramechanics to the development of planetary rovers can be divided into two phases (the R&D phase and exploration phase for rovers) corresponding to the high-fidelity and simplified terramechanics models. This paper also describes the current research status by providing an introduction to classical terramechanics and the experimental, theoretical, and numerical researches on terramechanics for planetary rovers. The application status of the terramechanics for planetary rovers is analyzed from the aspects of rover design, performance evaluation, planetary Soil parameter identification, dynamics simulation, mobility control, and path planning. Finally, the key issues for future research are discussed. The current planetary rovers are actually advanced wheeled mobile robots (WMRs), developed employing cutting-edge technologies from different fields. The terramechanics for planetary rovers is expected to present new challenges and applications for WMRs, making it possible to develop WMRs using the concepts of mechanics and dynamics.
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Wheel slip-sinkage and its prediction model of lunar rover
Journal of Central South University of Technology, 2010Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Jianguo TaoAbstract:In order to investigate wheel slip-sinkage problem, which is important for the design, control and simulation of lunar rovers, experiments were carried out with a wheel-Soil Interaction test system to measure the sinkage of three types of wheels in dimension with wheel lugs of different heights and numbers under a series of slip ratios (0−0.6). The curves of wheel sinkage versus slip ratio were obtained and it was found that the sinkage with slip ratio of 0.6 is 3−7 times of the static sinkage. Based on the experimental results, the slip-sinkage principle of lunar's rover lugged wheels (including the sinkage caused by longitudinal flow and side flow of Soil, and Soil digging of wheel lugs) was analyzed, and corresponding calculation equations were derived. All the factors that can cause slip sinkage were considered to improve the conventional wheel-Soil Interaction model, and a formula of changing the sinkage exponent with the slip ratio was established. Mathematical model for calculating the sinkage of wheel according to vertical load and slip ratio was developed. Calculation results show that this model can predict the slip-sinkage of wheel with high precision, making up the deficiency of Wong-Reece model that mainly reflects longitudinal slip-sinkage.
Zongquan Deng - One of the best experts on this subject based on the ideXlab platform.
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online estimation of terrain parameters and resistance force based on equivalent sinkage for planetary rovers in longitudinal skid
Mechanical Systems and Signal Processing, 2019Co-Authors: Zhen Liu, Liang Ding, Haibo Gao, Junlong Guo, Tianyou Guo, Zongquan DengAbstract:Abstract Wheel-Soil Interaction mechanics plays a crucial role for wheeled mobile robots (WMR) on rough and deformable terrains such as Martian and Lunar surfaces. Skid terramechanics is an essential component for WMRs and generates resistance force when a WMR brakes or on downhill slopes. The basis of classical terramechanics theories for WMRs – Bekker’s normal stress and Janosi’s shear stress equations – are so complex that the wheel-Soil Interaction force/torque equations are not amenable to closed form solutions, which seriously limits the application of terramechanics theories to WMRs. To establish analytical wheel-Soil Interaction expressions, the normal and shear stresses that can be characterized linearly by the proposed terrain stiffness and shear strength, respectively, are presented in this paper. Terrain stiffness and shear strength can be used to characterize terrain mechanical properties. Compared with the experimental data, the maximum relative error of the resistance forces estimated using these expressions at steady state is less than 7%. These validated expressions can be applied to estimate terrain parameters and resistance force online with high accuracy. Terrain’s stiffness and shear strength increase first, and then reach a constant. Before wheels entering steady state, the online estimated resistance force’s relative error is much higher, which can be explained using wheel’s vertical velocity.
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sinkage definition and visual detection for planetary rovers wheels on rough terrain based on wheel Soil Interaction boundary
Robotics and Autonomous Systems, 2017Co-Authors: Haibo Gao, Liang Ding, Baofeng Yuan, Guangjun Liu, Zongquan DengAbstract:Abstract Wheel sinkage detection is of tremendous significance for planetary rover mobility optimization control and prevention of serious wheel sinking. Wheel sinkage is regarded as the distance between the lowest point of the wheel in the Soil and the horizontal flat terrain on relative research. For rovers moving on rough terrains, the above definition is not reasonable because the horizontal flat terrain cannot be found. New wheel sinkage definition and detection method are proposed, based on vision. The sinkage definition rationality is analyzed for various terrain conditions. The discrete mathematical wheel sinkage calculation model, for which the input is acquired through a visual method, is built. Saturation of wheel–Soil Interaction image is adjusted by a dynamic piecewise nonlinear adjustment method The image is processed into a binary image based on HSI (Hue, Saturation, Intensity) color space. The wheel–Soil boundary is extracted from the corrected wheel region outline according to its morphological features. The wheel sinkage and equivalent terrain interface angles are calculated through the discrete mathematical wheel sinkage calculation model. Sinkage definition rationality and detection method applicability are experimentally validated in the four typical terrain conditions (flat, bulgy, sunken, and uneven terrains). Particularly, the experimental results prove the sinkage detection method has high accuracy for flat terrain, for which, the deviation of the sinkage modulus is less than 2% of the wheel radius. The sinkage detection method is proved to have fairly reasonable adaptability to complex illumination conditions, based on the experimental results for different illumination conditions.
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planetary rovers wheel Soil Interaction mechanics new challenges and applications for wheeled mobile robots
Intelligent Service Robotics, 2011Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Keiji Nagatani, Kazuya YoshidaAbstract:With the increasing challenges facing planetary exploration missions and the resultant increase in the performance requirements for planetary rovers, terramechanics (wheel---Soil Interaction mechanics) is playing an important role in the development of these rovers. As an extension of the conventional terramechanics theory for terrestrial vehicles, the terramechanics theory for planetary rovers, which is becoming a new research hotspot, is unique and puts forward many new challenging problems. This paper first discusses the significance of the study of wheel---Soil Interaction mechanics of planetary rovers and summarizes the differences between planetary rovers and terrestrial vehicles and the problems arising thereof. The application of terramechanics to the development of planetary rovers can be divided into two phases (the R&D phase and exploration phase for rovers) corresponding to the high-fidelity and simplified terramechanics models. This paper also describes the current research status by providing an introduction to classical terramechanics and the experimental, theoretical, and numerical researches on terramechanics for planetary rovers. The application status of the terramechanics for planetary rovers is analyzed from the aspects of rover design, performance evaluation, planetary Soil parameter identification, dynamics simulation, mobility control, and path planning. Finally, the key issues for future research are discussed. The current planetary rovers are actually advanced wheeled mobile robots (WMRs), developed employing cutting-edge technologies from different fields. The terramechanics for planetary rovers is expected to present new challenges and applications for WMRs, making it possible to develop WMRs using the concepts of mechanics and dynamics.
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Wheel slip-sinkage and its prediction model of lunar rover
Journal of Central South University of Technology, 2010Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Jianguo TaoAbstract:In order to investigate wheel slip-sinkage problem, which is important for the design, control and simulation of lunar rovers, experiments were carried out with a wheel-Soil Interaction test system to measure the sinkage of three types of wheels in dimension with wheel lugs of different heights and numbers under a series of slip ratios (0−0.6). The curves of wheel sinkage versus slip ratio were obtained and it was found that the sinkage with slip ratio of 0.6 is 3−7 times of the static sinkage. Based on the experimental results, the slip-sinkage principle of lunar's rover lugged wheels (including the sinkage caused by longitudinal flow and side flow of Soil, and Soil digging of wheel lugs) was analyzed, and corresponding calculation equations were derived. All the factors that can cause slip sinkage were considered to improve the conventional wheel-Soil Interaction model, and a formula of changing the sinkage exponent with the slip ratio was established. Mathematical model for calculating the sinkage of wheel according to vertical load and slip ratio was developed. Calculation results show that this model can predict the slip-sinkage of wheel with high precision, making up the deficiency of Wong-Reece model that mainly reflects longitudinal slip-sinkage.
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parameter identification for planetary Soil based on a decoupled analytical wheel Soil Interaction terramechanics model
Intelligent Robots and Systems, 2009Co-Authors: Liang Ding, Haibo Gao, Kazuya Yoshida, Keiji Nagatani, Zongquan DengAbstract:Identifying planetary Soil parameters is not only an important scientific goal, but also necessary for exploration rover to optimize its control strategy and realize high-fidelity simulation. An improved wheel-Soil Interaction mechanics model is introduced, and it is then simplified by linearizing the normal stress and shearing stress to derive closed-form analytical equations. Eight unknown Soil parameters are divided into three groups. The highly complicated coupled equations, each of which includes all the unknown Soil parameters, are then decoupled. Each decoupled equation contains one or two groups of Soil parameters, making it feasible to make a step-by-step identification of all the unknown parameters that characterize the Soil. Wheel-Soil Interaction experiments were performed for six kinds of wheels with different dimensions and wheel lugs on simulated planetary Soil. Soil parameters are identified with the measured data to validate the method, which are then used to predict wheel-Soil Interaction forces and torque, with a less than 10% margin of error. The improved model, decoupled analytical model, and Soil-characterizing method can play important roles in the development of both the planetary exploration rovers and the terrestrial vehicles.
Adem Dogangun - One of the best experts on this subject based on the ideXlab platform.
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Effect of foundation embedment on seismic behavior of elevated tanks considering fluid-structure-Soil Interaction
Soil Dynamics and Earthquake Engineering, 2007Co-Authors: Ramazan Livaoglu, Adem DogangunAbstract:This paper investigates the effects of foundation embedment on the seismic behavior of fluid-elevated tank-foundation–Soil system with a structural frame supporting the fluid containing tank. Six different Soil types defined in the well-known seismic codes were considered. Both the sloshing effects of the fluid and Soil-structure Interaction of the elevated tanks located on these six different Soils were included in the analyses. Fluid-elevated tank-foundation–Soil systems were modeled with the finite element (FE) technique. The fluid-structure Interaction was taken into account using Lagrangian fluid FE approximation implemented in the general purpose structural analysis computer program, ANSYS. FE model with viscous boundary was used to include elevated tank-foundation–Soil Interaction effects. The models were analyzed for the foundations with and without embedment. It was found that the tank roof displacements were affected significantly by the embedment in soft Soil, however, this effect was smaller for stiff Soil types. Except for soft Soil types, embedment did not affect the other response parameters, such as sloshing displacement, of the systems considered in this study.
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simplified seismic analysis procedures for elevated tanks considering fluid structure Soil Interaction
Journal of Fluids and Structures, 2006Co-Authors: Ramazan Livaoglu, Adem DogangunAbstract:Abstract This paper presents a review of simplified seismic design procedures for elevated tanks and the applicability of general-purpose structural analyses programs to fluid–structure–Soil Interaction problems for these kinds of tanks. Ten models are evaluated by using mechanical and finite-element modelling techniques. An added mass approach for the fluid–structure Interaction, and the massless foundation and substructure approaches for the Soil–structure Interactions are presented. The applicability of these ten models for the seismic design of the elevated tanks with four different subSoil classes are emphasized and illustrated. Designers may use the models presented in this study without using any fluid and/or special Soil elements. From the models defined here, single lumped-mass models underestimate the base shear and the overturning moment. Because almost all the other assumptions for the fixed base give similar results, any method could be used, but the distributed added mass with the sloshing mass is more appropriate than the lumped mass assumptions for finite-element modelling, and is recommended in this study.
Haibo Gao - One of the best experts on this subject based on the ideXlab platform.
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online estimation of terrain parameters and resistance force based on equivalent sinkage for planetary rovers in longitudinal skid
Mechanical Systems and Signal Processing, 2019Co-Authors: Zhen Liu, Liang Ding, Haibo Gao, Junlong Guo, Tianyou Guo, Zongquan DengAbstract:Abstract Wheel-Soil Interaction mechanics plays a crucial role for wheeled mobile robots (WMR) on rough and deformable terrains such as Martian and Lunar surfaces. Skid terramechanics is an essential component for WMRs and generates resistance force when a WMR brakes or on downhill slopes. The basis of classical terramechanics theories for WMRs – Bekker’s normal stress and Janosi’s shear stress equations – are so complex that the wheel-Soil Interaction force/torque equations are not amenable to closed form solutions, which seriously limits the application of terramechanics theories to WMRs. To establish analytical wheel-Soil Interaction expressions, the normal and shear stresses that can be characterized linearly by the proposed terrain stiffness and shear strength, respectively, are presented in this paper. Terrain stiffness and shear strength can be used to characterize terrain mechanical properties. Compared with the experimental data, the maximum relative error of the resistance forces estimated using these expressions at steady state is less than 7%. These validated expressions can be applied to estimate terrain parameters and resistance force online with high accuracy. Terrain’s stiffness and shear strength increase first, and then reach a constant. Before wheels entering steady state, the online estimated resistance force’s relative error is much higher, which can be explained using wheel’s vertical velocity.
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sinkage definition and visual detection for planetary rovers wheels on rough terrain based on wheel Soil Interaction boundary
Robotics and Autonomous Systems, 2017Co-Authors: Haibo Gao, Liang Ding, Baofeng Yuan, Guangjun Liu, Zongquan DengAbstract:Abstract Wheel sinkage detection is of tremendous significance for planetary rover mobility optimization control and prevention of serious wheel sinking. Wheel sinkage is regarded as the distance between the lowest point of the wheel in the Soil and the horizontal flat terrain on relative research. For rovers moving on rough terrains, the above definition is not reasonable because the horizontal flat terrain cannot be found. New wheel sinkage definition and detection method are proposed, based on vision. The sinkage definition rationality is analyzed for various terrain conditions. The discrete mathematical wheel sinkage calculation model, for which the input is acquired through a visual method, is built. Saturation of wheel–Soil Interaction image is adjusted by a dynamic piecewise nonlinear adjustment method The image is processed into a binary image based on HSI (Hue, Saturation, Intensity) color space. The wheel–Soil boundary is extracted from the corrected wheel region outline according to its morphological features. The wheel sinkage and equivalent terrain interface angles are calculated through the discrete mathematical wheel sinkage calculation model. Sinkage definition rationality and detection method applicability are experimentally validated in the four typical terrain conditions (flat, bulgy, sunken, and uneven terrains). Particularly, the experimental results prove the sinkage detection method has high accuracy for flat terrain, for which, the deviation of the sinkage modulus is less than 2% of the wheel radius. The sinkage detection method is proved to have fairly reasonable adaptability to complex illumination conditions, based on the experimental results for different illumination conditions.
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planetary rovers wheel Soil Interaction mechanics new challenges and applications for wheeled mobile robots
Intelligent Service Robotics, 2011Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Keiji Nagatani, Kazuya YoshidaAbstract:With the increasing challenges facing planetary exploration missions and the resultant increase in the performance requirements for planetary rovers, terramechanics (wheel---Soil Interaction mechanics) is playing an important role in the development of these rovers. As an extension of the conventional terramechanics theory for terrestrial vehicles, the terramechanics theory for planetary rovers, which is becoming a new research hotspot, is unique and puts forward many new challenging problems. This paper first discusses the significance of the study of wheel---Soil Interaction mechanics of planetary rovers and summarizes the differences between planetary rovers and terrestrial vehicles and the problems arising thereof. The application of terramechanics to the development of planetary rovers can be divided into two phases (the R&D phase and exploration phase for rovers) corresponding to the high-fidelity and simplified terramechanics models. This paper also describes the current research status by providing an introduction to classical terramechanics and the experimental, theoretical, and numerical researches on terramechanics for planetary rovers. The application status of the terramechanics for planetary rovers is analyzed from the aspects of rover design, performance evaluation, planetary Soil parameter identification, dynamics simulation, mobility control, and path planning. Finally, the key issues for future research are discussed. The current planetary rovers are actually advanced wheeled mobile robots (WMRs), developed employing cutting-edge technologies from different fields. The terramechanics for planetary rovers is expected to present new challenges and applications for WMRs, making it possible to develop WMRs using the concepts of mechanics and dynamics.
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Wheel slip-sinkage and its prediction model of lunar rover
Journal of Central South University of Technology, 2010Co-Authors: Liang Ding, Haibo Gao, Zongquan Deng, Jianguo TaoAbstract:In order to investigate wheel slip-sinkage problem, which is important for the design, control and simulation of lunar rovers, experiments were carried out with a wheel-Soil Interaction test system to measure the sinkage of three types of wheels in dimension with wheel lugs of different heights and numbers under a series of slip ratios (0−0.6). The curves of wheel sinkage versus slip ratio were obtained and it was found that the sinkage with slip ratio of 0.6 is 3−7 times of the static sinkage. Based on the experimental results, the slip-sinkage principle of lunar's rover lugged wheels (including the sinkage caused by longitudinal flow and side flow of Soil, and Soil digging of wheel lugs) was analyzed, and corresponding calculation equations were derived. All the factors that can cause slip sinkage were considered to improve the conventional wheel-Soil Interaction model, and a formula of changing the sinkage exponent with the slip ratio was established. Mathematical model for calculating the sinkage of wheel according to vertical load and slip ratio was developed. Calculation results show that this model can predict the slip-sinkage of wheel with high precision, making up the deficiency of Wong-Reece model that mainly reflects longitudinal slip-sinkage.
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parameter identification for planetary Soil based on a decoupled analytical wheel Soil Interaction terramechanics model
Intelligent Robots and Systems, 2009Co-Authors: Liang Ding, Haibo Gao, Kazuya Yoshida, Keiji Nagatani, Zongquan DengAbstract:Identifying planetary Soil parameters is not only an important scientific goal, but also necessary for exploration rover to optimize its control strategy and realize high-fidelity simulation. An improved wheel-Soil Interaction mechanics model is introduced, and it is then simplified by linearizing the normal stress and shearing stress to derive closed-form analytical equations. Eight unknown Soil parameters are divided into three groups. The highly complicated coupled equations, each of which includes all the unknown Soil parameters, are then decoupled. Each decoupled equation contains one or two groups of Soil parameters, making it feasible to make a step-by-step identification of all the unknown parameters that characterize the Soil. Wheel-Soil Interaction experiments were performed for six kinds of wheels with different dimensions and wheel lugs on simulated planetary Soil. Soil parameters are identified with the measured data to validate the method, which are then used to predict wheel-Soil Interaction forces and torque, with a less than 10% margin of error. The improved model, decoupled analytical model, and Soil-characterizing method can play important roles in the development of both the planetary exploration rovers and the terrestrial vehicles.
T. Barfoot - One of the best experts on this subject based on the ideXlab platform.
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Experimental and simulation results of wheel-Soil Interaction for planetary rovers
2005 IEEE RSJ International Conference on Intelligent Robots and Systems, 2005Co-Authors: R. Bauer, W. Leung, T. BarfootAbstract:The ability to predict rover locomotion performance is critical during the design, validation and operational phases of a planetary robotic mission. Predicting locomotion performance depends on the ability to accurately characterize the wheel-Soil Interactions. In this research, wheel-Soil Interaction experiments were carried out on a single-wheel testbed and the results were compared with a single-wheel dynamic computer simulator which was developed in Matlab and Simulink's SimMechanics toolbox using a commercially-available wheel-Soil Interaction computer model called AESCO Soft Soil Tire Model (AS/sup 2/TM). Two different tire treads were used and compared in this study. There is good agreement between experimental and simulation results for wheel sinkage as a function of slip ratio; however, more investigation is needed to understand the differences observed for the drawbar pull and motor torque results.
