scholarly journals Soil Parameter Identification and Driving Force Prediction for Wheel-Terrain Interaction

10.5772/6225 ◽  
2008 ◽  
Vol 5 (4) ◽  
pp. 35 ◽  
Author(s):  
Suksun Hutangkabodee ◽  
Yahya Zweiri ◽  
Lakmal Seneviratne ◽  
Kaspar Althoefer
Keyword(s):  
Driving Force ◽  
Driving Forces ◽  
Interaction Model ◽  
Soil Parameters ◽  
Wheel Slip ◽  
Force Prediction ◽  
High Inflation ◽  
Generalized Newton ◽  
Drawbar Pull ◽  
Wheeled Vehicles

This paper considers wheeled vehicles traversing unknown terrain, and proposes an approach for identifying the unknown soil parameters required for vehicle driving force prediction (drawbar pull prediction). The predicted drawbar pull can potentially be employed for traversability prediction, traction control, and trajectory following which, in turn, improve overall performance of off-road wheeled vehicles. The proposed algorithm uses an approximated form of the wheel-terrain interaction model and the Generalized Newton Raphson method to identify terrain parameters in real-time. With few measurements of wheel slip, i, vehicle sinkage, z, and drawbar pull, DP, samples, the algorithm is capable of identifying all the soil parameters required to predict vehicle driving forces over an entire range of wheel slip. The algorithm is validated with experimental data from a wheel-terrain interaction test rig. The identified soil parameters are used to predict the drawbar pull with good accuracy. The technique presented in this paper can be applied to any vehicle with rigid wheels or deformable wheels with relatively high inflation pressure, to predict driving forces in unknown environments.

scholarly journals Driving forces on dislocations: finite element analysis in the context of the non-singular dislocation theory

2021 ◽  
Author(s):  
Xiandong Zhou ◽  
Christoph Reimuth ◽  
Peter Stein ◽  
Bai-Xiang Xu
Keyword(s):  
Finite Element ◽  
Dislocation Loop ◽  
Driving Force ◽  
Complex Geometry ◽  
Driving Forces ◽  
Singular Solutions ◽  
Dislocation Model ◽  
Configurational Force ◽  
Element Analysis ◽  
Dislocation Configuration

AbstractThis work presents a regularized eigenstrain formulation around the slip plane of dislocations and the resultant non-singular solutions for various dislocation configurations. Moreover, we derive the generalized Eshelby stress tensor of the configurational force theory in the context of the proposed dislocation model. Based on the non-singular finite element solutions and the generalized configurational force formulation, we calculate the driving force on dislocations of various configurations, including single edge/screw dislocation, dislocation loop, interaction between a vacancy dislocation loop and an edge dislocation, as well as a dislocation cluster. The non-singular solutions and the driving force results are well benchmarked for different cases. The proposed formulation and the numerical scheme can be applied to any general dislocation configuration with complex geometry and loading conditions.

Driving forces and structural changes of China as a market provider for Korea

2018 ◽  
Vol 22 (3) ◽  
pp. 194-211 ◽  
Author(s):  
Yongqi Feng ◽  
Tianshu Zhang
Keyword(s):  
Steady State ◽  
Driving Force ◽  
Design Methodology ◽  
Structural Changes ◽  
Driving Forces ◽  
Consumption Expenditure ◽  
Input Output ◽  
Content Type ◽  
Fixed Capital Formation ◽  
The Impact

Purpose The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.

Study on the Steering Performance of Dual-Motor Drive Track Bulldozer

2013 ◽  
Vol 427-429 ◽  
pp. 133-136
Author(s):  
Qiang Song ◽  
Pu Zeng
Keyword(s):  
Simulation Model ◽  
Dynamic Characteristics ◽  
Driving Force ◽  
Driving Forces ◽  
Small Radius ◽  
Motor Drive ◽  
Matlab Simulink ◽  
Simulation Results ◽  
Two Sides

The driving theory and the dynamic characteristics of small radius steering, medium radius steering and big radius steering is analyzed, and the simulation model is established under Matlab/Simulink. Then the track bulldozers steering performance of the three sheerings is simulated. The results show that, at different steering modes, the running states of the two sides driving motors are not the same, and the track driving forces of the two sides vary widely. The track driving force is great in the small radius steering model, while small in the medium and big radius steering models. The simulation results lay the foundation for dual-motor drive track bulldozers steering performance matching.

Experimental Validation of a Volumetric Planetary Rover Wheel/Soil Interaction Model

2013 ◽  
Author(s):  
Willem Petersen ◽  
John McPhee
Keyword(s):  
Contact Force ◽  
Interaction Model ◽  
Contact Model ◽  
Soil Parameters ◽  
Model Parameters ◽  
Force Model ◽  
Normal Contact ◽  
Planetary Rover ◽  
Normal Contact Force ◽  
Contact Force Model

For the multibody simulation of planetary rover operations, a wheel-soil contact model is necessary to represent the forces and moments between the tire and the soft soil. A novel nonlinear contact modelling approach based on the properties of the hypervolume of interpenetration is validated in this paper. This normal contact force model is based on the Winkler foundation model with nonlinear spring properties. To fully define the proposed normal contact force model for this application, seven parameters are required. Besides the geometry parameters that can be easily measured, three soil parameters representing the hyperelastic and plastic properties of the soil have to be identified. Since it is very difficult to directly measure the latter set of soil parameters, they are identified by comparing computer simulations with experimental results of drawbar pull tests performed under different slip conditions on the Juno rover of the Canadian Space Agency (CSA). A multibody dynamics model of the Juno rover including the new wheel/soil interaction model was developed and simulated in MapleSim. To identify the wheel/soil contact model parameters, the cost function of the model residuals of the kinematic data is minimized. The volumetric contact model is then tested by using the identified contact model parameters in a forward dynamics simulation of the rover on an irregular 3-dimensional terrain and compared against experiments.

scholarly journals The Formation of Deposits on the Walls of the Pores in the Filtering Process

2019 ◽  
Vol 14 (2) ◽  
pp. 15-22
Author(s):  
Yu. A. Taran ◽  
A. V. Kozlov ◽  
A. L. Taran
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Driving Force ◽  
Nonequilibrium Thermodynamics ◽  
Driving Forces ◽  
Solid Particles ◽  
Original Structure ◽  
Small Particles ◽  
Filtration Process ◽  
Filter Unit

The aim of the work is to consider the mechanism of clogging the pores of the filter unit by small particles from the flow of filtrate inside them. Theoretical ideas about the process of filtering with the deposition of small particles from the filtrate on the pore walls and attribution of its fundamentals to restructuring from the original structure to the final structure allow to describe the process of clogging the pores using well studied concepts of known processes with phase transformations (in particular, crystallization). Based on this analogy and the approach to the description of the transformation of the "old" structure into a "new" one in time, using experimental data and their processing we calculated the rate of nucleation of the sediment centers (ωnucl), the linear (υlin) and volumetric rates of sediment plaques growth in the pores of the filter unit at different values of the process driving force, at different pressure difference in the system, and at different concentrations of solid particles in the suspension. Interpolation and extrapolation dependences were obtained for analyzing the mechanisms of sediments formation and growth for determining and calculating these (ωnucl, υlin) rates. Using the concepts of nonequilibrium thermodynamics to assess the influence of the driving forces we studied their influence (changes in the concentration of solid particles in the filtrate suspension and pressure drop across the filtering layer) on the dynamics of the filtration process. Using the data obtained it is possible to find the degree of clogging of through pores, which determines the filtration conditions, the filter septum type, and the filter overall dimensions.

The Coupling Effect of Driving Forces to the Anti-Gravity Flow in the Spiral Micro-Channel

2011 ◽  
Author(s):  
Yan Li ◽  
Shuchao Zhang ◽  
Ning Mei
Keyword(s):  
Driving Force ◽  
Driving Forces ◽  
Coupling Effect ◽  
Three Dimensional ◽  
Horizontal Tube ◽  
Gravity Flow ◽  
Micro Channel ◽  
Reciprocal Relations ◽  
Coupling Relationship ◽  
Onsager Reciprocal Relations

In this paper, the anti-gravity flow in the spiral micro-channel on the surface of horizontal tube was visualized by the three-dimensional ultra-microscope system. The coupling relationship between the driving force and the flow was studied by Onsager reciprocal relations. The results show that the formation of the anti-gravity flow in the spiral micro-channel on the surface of horizontal tube is impacted by the combining effect of several factors, such as the capillary pressure, wettability, temperature, and bubbles.

Obstacle negotiation analysis of track-legged robot based on terramechanics

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zhu Hongbiao ◽  
Yueming Liu ◽  
Weidong Wang ◽  
Zhijiang Du
Keyword(s):  
Kinematic Model ◽  
Interaction Model ◽  
Experimental Results ◽  
Physical Parameters ◽  
Negotiation Analysis ◽  
Content Type ◽  
Practical Applications ◽  
Loose Soil ◽  
Key Steps ◽  
Drawbar Pull

Purpose This paper aims to present a new method to analyze the robot’s obstacle negotiation based on the terramechanics, where the terrain physical parameters, the sinkage and the slippage of the robot are taken into account, to enhance the robot’s trafficability. Design/methodology/approach In this paper, terramechanics is used in motion planning for all-terrain obstacle negotiation. First, wheel/track-terrain interaction models are established and used to analyze traction performances in different locomotion modes of the reconfigurable robot. Next, several key steps of obstacle-climbing are reanalyzed and the sinkage, the slippage and the drawbar pull are obtained by the models in these steps. In addition, an obstacle negotiation analysis method on loose soil is proposed. Finally, experiments in different locomotion modes are conducted and the results demonstrate that the model is more suitable for practical applications than the center of gravity (CoG) kinematic model. Findings Using the traction performance experimental platform, the relationships between the drawbar pull and the slippage in different locomotion modes are obtained, and then the traction performances are obtained. The experimental results show that the relationships obtained by the models are in good agreement with the measured. The obstacle-climbing experiments are carried out to confirm the availability of the method, and the experimental results demonstrate that the model is more suitable for practical applications than the CoG kinematic model. Originality/value Comparing with the results without considering Terramechanics, obstacle-negotiation analysis based on the proposed track-terrain interaction model considering Terramechanics is much more accurate than without considering Terramechanics.

Indicators of Possible Driving Forces for the Spread of Quechua and Aymara Reflected in the Archaeology of Cuzco

2012 ◽  
Author(s):  
GORDON F. McEWAN
Keyword(s):  
Cultural History ◽  
Driving Force ◽  
Driving Forces ◽  
Alternative Possibilities ◽  
The Past ◽  
The North ◽  
The Andes ◽  
Inca Empire ◽  
Culture History ◽  
History Of

Linguistic studies have shown that the traditional idea that the expansion of the Inca Empire was the driving force behind the spread of all Quechua cannot be correct. Across much of its distribution, Quechua has far greater time-depth than can be accounted for by the short-lived Inca Empire. Linguistics likewise suggests that Aymara spread not from the south into Cuzco in the late Pre-Inca period, but also from an origin to the north. Alternative explanations must be sought for the expansion of these language families in the culture history of the Andes. Archaeological studies over the past two decades now provide a broad, generally agreed-upon outline of the cultural history of the Cuzco region. This chapter applies those findings to examine alternative possibilities for the driving forces that spread Quechua and Aymara, offering a clearer cross-disciplinary view of Andean prehistory.

Geographies of Agri-food

2006 ◽  
Author(s):  
Kevin Morgan ◽  
Terry Marsden ◽  
Jonathan Murdoch
Keyword(s):  
Driving Force ◽  
Driving Forces ◽  
Transformation Process ◽  
Specific Reference ◽  
Industrial System ◽  
Corporate Capital ◽  
Agricultural Transformation ◽  
Agrarian Question ◽  
General Terms ◽  
Production And Consumption

Chapters 1 and 2 have reviewed the contemporary theoretical and policy context of agri-food with specific reference to Europe and North America. In this chapter we turn our attention to the nature of the new agri-food geographies. What are the driving forces behind these geographies, and how do they play themselves out across time and space? This theme is central to the more detailed treatment of three different regions (Tuscany, California, and Wales) in succeeding chapters. Here, we introduce a conceptual framework that helps us to understand the new agri-food geographies. The chapter starts by outlining the nature of the conventional agri-industrial system. In general terms, we see this as a system that leads to a process of deterritorialization of foods. That is not to say that it comes without any actual geography; rather, its geographies are the result of corporate capitals’ attempts to continue to intensify and to appropriate some of the functions of agriculture in ways that stretch the links, networks, and chains between production and consumption spheres. We then place this trend in conceptual juxtaposition with the more recent forces of reterritorialization (or what some scholars term ‘relocalization’), a process whereby local and regional geographies come back again to play a central role in reshaping food production and consumption systems. We argue here that it is important to see these conflicting geographical forces as distinctive, even though both processes may indeed be operating—to varying degrees and in different ways—in the same region or locality at the same time. This is at the heart of our contingent notion of ‘worlds of food’. Throughout the twentieth century, agri-industrialism struggled with resolving Kautsky’s formulation of the agrarian question, that is, how to continue to intensify production and appropriate some farming functions in processing and agri-industry while at the same time maintaining some sort of ecological or natural balance in the agricultural transformation process (Kautsky, 1988; Goodman and Watts, 1997). In the agri-industrial model, the driving force was corporate capital.

scholarly journals An Integrated Investigation of Spatiotemporal Habitat Quality Dynamics and Driving Forces in the Upper Basin of Miyun Reservoir, North China

2018 ◽  
Vol 10 (12) ◽  
pp. 4625 ◽  
Author(s):  
Shengjun Yan ◽  
Xuan Wang ◽  
Yanpeng Cai ◽  
Chunhui Li ◽  
Rui Yan ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Habitat Quality ◽  
Driving Force ◽  
North China ◽  
Population Change ◽  
Driving Forces ◽  
Policy Formulation ◽  
Force Analysis ◽  
Miyun Reservoir ◽  
Driving Force Analysis

Understanding changes in habitat quality and the driving forces of these changes at landscape scales is a critical part of effective ecosystem management. The present study investigated spatiotemporal habitat quality dynamics and related driving forces from 2005 to 2015 in the upper basin of Miyun Reservoir in North China by constructing an effective framework integrated InVEST and binary logistic regression models. This framework expanded the driving force analysis into an assessment of changes in habitat quality and intuitively verified the effectiveness of relevant environmental policies. The proposed method of combining the equidistant random sampling method and the method of introducing spatial lag variables in logistic regression equation can effectively solve spatial autocorrelation with a large enough number of sampling points. Overall, habitat quality improved during the study period. Spatially, a concentrated loss of habitat occurred in the southeastern part of the basin between the reservoir and mountainous areas, while other areas gradually recovered. Driving force analysis showed that lower elevation mountain land, gentle slopes, locations near rural land or roads, larger areas of grain cultivation, and areas with little population change had a higher likelihood of having changed in habitat quality in the upper basin of Miyun Reservoir. These results suggested that the present policy of protecting the ecosystem had a positive effect on improving habitat quality. In the future, the human activity management related to habitat quality needs to be strengthened. The present study would provide a reference for land use policy formulation and biodiversity conservation.

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