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The electric-tracked intelligent detection device is extensively used in engineering exploration and construction. However, in unstructured and complex terrains, its stability is challenged by a high center of gravity and poor road conditions, making the enhancement of its stability analysis crucial. This study is based on tracked vehicle models, constructing kinematic and dynamic equations for the device, and developing virtual and physical prototypes. Combining theoretical analysis, virtual simulations, and physical testing, the study analyzes motion parameters under typical conditions through numerical calculations and simulations. It examines the device's dynamic characteristics during rapid turns in unstructured terrains. The research identifies variations in motion parameters, determines dynamic stability thresholds, and refines stability analysis methods applicable to the device, establishing evaluation criteria with multiple parameters and weight vectors. In conclusion, the developed models and prototypes help us understand the electric-tracked intelligent detection device's dynamic characteristics and instability thresholds, enhancing its stability and operational efficiency and providing a theoretical foundation for related engineering machinery development. [ABSTRACT FROM AUTHOR]

The electric-tracked intelligent detection device is extensively used in engineering exploration and construction. However, in unstructured and complex terrains, its stability is challenged by a high center of gravity and poor road conditions, making the enhancement of its stability analysis crucial. This study is based on tracked vehicle models, constructing kinematic and dynamic equations for the device, and developing virtual and physical prototypes. Combining theoretical analysis, virtual simulations, and physical testing, the study analyzes motion parameters under typical conditions through numerical calculations and simulations. It examines the device’s dynamic characteristics during rapid turns in unstructured terrains. The research identifies variations in motion parameters, determines dynamic stability thresholds, and refines stability analysis methods applicable to the device, establishing evaluation criteria with multiple parameters and weight vectors. In conclusion, the developed models and prototypes help us understand the electric-tracked intelligent detection device’s dynamic characteristics and instability thresholds, enhancing its stability and operational efficiency and providing a theoretical foundation for related engineering machinery development.

After the occurrence of natural disasters or accidents， robots are often needed to go deeply into the disaster site to find out the situation or provide assistance. The structure of wheel-legged planetary probe robot is successfully applied by reference， for the special unstructured terrain of the post-disaster site， a new search and rescue robot with five wheels and four swinging arms is designed for the special unstructured terrain in the disaster site. Through the parameter design and statics analysis of the key components， the rationality of static feature is verified， and the mathematically modeling of process of obstacle crossing is carried out， the factors that affect the height of the robot obstacle surmounting are obtained. Then the virtual prototype simulation is carried out to verify the rationality of the dynamic characteristics and the correctness of the mathematical modeling. Finally， an experimental platform is built to verify the obstacle surmounting ability of the designed robot， which provides a theoretical basis for the design of similar wheeled robots in the future and has a certain reference significance.

In this paper, a crawler-type wall-climbing robot with negative pressure adsorption is designed. The dynamic model of the robot is established based on the method of discretizing the force load of the track shoe. The correctness of the kinematic model and dynamic model is proved by comparing two different ways of virtual prototype simulation and prototype experiment. According to the simulation results of the dynamic model and virtual prototype, the influence of design parameters on the motion performance of the wall-climbing robot is analyzed. The smaller the speed difference between the two tracks of the robot, the longer the gauge between the two tracks, and the greater the inclination of the adsorption wall, the larger the turning radius of the robot will be. The research content based on this paper can provide a new design optimization method and theoretical basis for improving crawler wall-climbing robots and crawler vehicles. [ABSTRACT FROM AUTHOR]

• Failure mechanism of track travelling unit of hydraulic excavator. • Whole excavator experiments were carried out. • Non-linear finite element analysis of the supporting wheel was carried out. • Determine the two working conditions and load values of the supporting wheel with the highest force through the simulation results. • A test rig was set up to analyse the failure of the strut wheel sealing assembly. In order to explore the specific reasons for the oil leakage of the supporting wheel, and to determine the specific location of the oil leakage of the supporting wheel, this paper carries out the excavator machine test and the finite element simulation analysis of the supporting wheel assembly, and designs and manufactures the supporting wheel test bench. It was found that the lubricant was leaking from the gap between the supporting wheel body and the axle seat. Through further tests, it was finally determined that the floating seal rubber ring had undergone plastic deformation during the working process of the supporting wheel, resulting in oil leakage from the supporting wheel. The results of the study also emphasized the importance of temperature on the seal failure of the support wheel. An improvement programme for the seal failure of the support wheel was also proposed. [ABSTRACT FROM AUTHOR]

Abstract As for the complex operational tasks in the unstructured environment with narrow workspace and numerous obstacles, the traditional robots cannot accomplish these mentioned complex operational tasks and meet the dexterity demands. The hyper-redundant bionic robots can complete complex tasks in the unstructured environments by simulating the motion characteristics of the elephant’s trunk and octopus tentacles. Compared with traditional robots, the hyper-redundant bionic robots can accomplish complex tasks because of their flexible structure. A hyper-redundant elephant’s trunk robot (HRETR) with an open structure is developed in this paper. The content includes mechanical structure design, kinematic analysis, virtual prototype simulation, control system design, and prototype building. This design is inspired by the flexible motion of an elephant’s trunk, which is expansible and is composed of six unit modules, namely, 3UPS-PS parallel in series. First, the mechanical design of the HRETR is completed according to the motion characteristics of an elephant’s trunk and based on the principle of mechanical bionic design. After that, the backbone mode method is used to establish the kinematic model of the robot. The simulation software SolidWorks and ADAMS are combined to analyze the kinematic characteristics when the trajectory of the end moving platform of the robot is assigned. With the help of ANSYS, the static stiffness of each component and the whole robot is analyzed. On this basis, the materials of the weak parts of the mechanical structure and the hardware are selected reasonably. Next, the extensible structures of software and hardware control system are constructed according to the modular and hierarchical design criteria. Finally, the prototype is built and its performance is tested. The proposed research provides a method for the design and development for the hyper-redundant bionic robot.

As for the complex operational tasks in the unstructured environment with narrow workspace and numerous obstacles, the traditional robots cannot accomplish these mentioned complex operational tasks and meet the dexterity demands. The hyper-redundant bionic robots can complete complex tasks in the unstructured environments by simulating the motion characteristics of the elephant's trunk and octopus tentacles. Compared with traditional robots, the hyper-redundant bionic robots can accomplish complex tasks because of their flexible structure. A hyper-redundant elephant's trunk robot (HRETR) with an open structure is developed in this paper. The content includes mechanical structure design, kinematic analysis, virtual prototype simulation, control system design, and prototype building. This design is inspired by the flexible motion of an elephant's trunk, which is expansible and is composed of six unit modules, namely, 3UPS-PS parallel in series. First, the mechanical design of the HRETR is completed according to the motion characteristics of an elephant's trunk and based on the principle of mechanical bionic design. After that, the backbone mode method is used to establish the kinematic model of the robot. The simulation software SolidWorks and ADAMS are combined to analyze the kinematic characteristics when the trajectory of the end moving platform of the robot is assigned. With the help of ANSYS, the static stiffness of each component and the whole robot is analyzed. On this basis, the materials of the weak parts of the mechanical structure and the hardware are selected reasonably. Next, the extensible structures of software and hardware control system are constructed according to the modular and hierarchical design criteria. Finally, the prototype is built and its performance is tested. The proposed research provides a method for the design and development for the hyper-redundant bionic robot. [ABSTRACT FROM AUTHOR]

The moving mechanism configuration has a major impact on the static stability,dynamic stability and driving force of the wheeled service robot. Taking the six-wheel mobile underpan as the object,the relationships between the wheel layout and the static stability,dynamic stability,driving force to cross obstacle and turn are analyzed. A multi-objective optimization model for wheel layout is established and the optimal solution is derived by using MATLAB genetic algorithm toolbox. Assuming the factors of pitch angle,roll angle and drive torque as evaluation indicators,motion simulation of the mobile underpan is carried out by the virtual prototyping technology. The results show that the pitch angle and roll angle after optimization are decreased by17. 6% and 27. 2%,respectively. The average value and mean square of drive torque are decreased by 2. 8%and 3. 6%,respectively. It is beneficial to the transmission performance and endurance of the mobile underpan. The results also verify the correctness and validity of the established multi-objective optimization model.

The rehabilitation training is the key process for restoring the normal physiological functions for patients. The rehabilitation robot has been developed for the reason that it can help patient complete the repeated training process. However, most of rehabilitation robots are based on parallel mechanism with coupled motion, which leads to the kinematic complication and unreliability. In order to overcome the weakness resulted from coupled motion, this paper presents a RRR-P a RPS-RHJ type ankle rehabilitation parallel mechanism with three rotation degrees of freedom and motion decoupling function. Firstly, the inverse kinematics results are obtained by using the transformation of coordinates, and the motion decoupling characteristics is analyzed. Then according to the Euler kinematic equations, the Jacobian matrix is computed. On this basis, the singular configuration is analyzed. Finally, the comparative analysis between 3-SPS/S and RRR-PaRPS-RHJ ankle rehabilitation mechanism is performed by ADAMS. The results show that the present mechanism has good kinematic character. It can avoid the driving interference caused by the motion coupling, which improves the comfort and reliability of the training process. • This paper presents a RRR-P a RPS-RHJ ankle rehabilitation mechanism with 3 DOFs and motion decoupling function. • Kinematic performance has been studied, which can be the reference of the further research for the motion coupling. • ompared with 3-SPS/S ankle robot，present ankle robot proposed can avoid the driving interference. [ABSTRACT FROM AUTHOR]

The electromechanical coupling performance of crawler machinery is investigated. A dynamic equation of electromechanical coupling of crawler machinery is established under multi-typical working conditions. The variation in performance of electromechanical parameters during unstable operations over time is analyzed using the virtual prototype and electromechanical coupling model of crawler machinery. The correctness of the electromechanical coupling model is confirmed by comparing the theoretical analysis, virtual prototype simulation, and physical prototype results. This study provides accurate and valuable theoretical methods and fundamental knowledge to analyze the electromechanical and road driving performance as well as to develop and design a crawler machinery. [ABSTRACT FROM AUTHOR]

The test method and simulation technology about the non-full loading firing dispersion for multiple launch rocket system (MLRS) are studied. A new method for reducing the rocket consumption in dispersion test of MLRS is presented. A parameterized simulation model of MLRS is established by use of the virtual-prototype-based dynamics simulation technology and multi-island genetic algorithm. The proposed model is integrated in the multidisciplinary optimization software ISIGHT. Based on the idea of equal initial disturbance deviation, a firing dispersion test method of a non-full loading MLRS is presented by using the multi island genetic algorithm as the optimization control strategy. The initial disturbance and firing dispersion are calculated via simulation in the case of full loading salvo and non-full loading continuous fire. The simulated results show that the two schemes have the same initial disturbance, and the system firing dispersion is satisfied with F test, which proves that the proposed firing dispersion test method with the non-full loading for MLRS is completely feasible. The rocket consumption in firing dispersion test of a MLRS can be decreased by 41.7% using the proposed non-full loading scheme. [ABSTRACT FROM AUTHOR]

Large capacity shovels are deployed in surface mining operations for achieving economic bulk production targets. These shovels use crawler tracks for effective terrain engagement in these environments. Shovel reliability, maintainability, availability and efficiency depend on the service life of the crawler tracks. In rugged and challenging terrains, crawler wear, tear, cracks and failure are extensive resulting in prolonged downtimes with severe economic implications. In particular, crawler shoe wear, tear, cracks and fatigue failures can be expensive in terms of maintenance costs and production losses. No fundamental research has been undertaken to understand the crawler-formation interactions in challenging and rugged terrains in surface mining operations. This study forms the foundations for providing long-term solutions to crawler failure problems. The kinematic equations governing the crawler-formation interactions have been formulated to characterise the crawler motions during shovel production. These equations capture the motions governing the link pin joint, oil sand terrain joint and driving constraints based on the multi-body rigid theory. Crawler propel is achieved by using prescribed velocities along a translational degree of freedom (DOF) and a translational and rotational DOF. The crawler kinematic solutions show that the 3-D crawler–terrain model results in 132 DOFs and requires dynamic modelling to obtain the unknown degrees of freedom. A 3-D virtual prototype model is built to capture the crawler-formation interaction in MSC ADAMS based on the rigid body crawler kinematics. The virtual prototype simulator is supplied with mass properties of crawler shoe, mass, stiffness and damping characteristics of oil sand and external loads due to machine weight and contact forces to obtain the time variation of position, velocity and acceleration for the crawler–terrain engagement for given driving constraints. The results from the driving constraints yield a non-linear longitudinal motion of the crawler track assembly. The crawler track lateral and vertical displacements during translation-only motion fluctuates with maximum magnitudes of 0.7 and 3.6 cm. Similarly the fluctuating longitudinal, lateral and vertical velocities and accelerations have maximum magnitudes of 0.22, 0.046 and 0.56 m/s and 7.41, 1.73, and 34.9 m/s2, respectively. This research provides a strong foundation for further study on developing flexible crawler track model for predicting crawler shoes dynamic stress distributions, cracks development and propagation and fatigue analysis during shovel operations. [ABSTRACT FROM AUTHOR]

Abstract: Cable shovels are capital-intensive equipment, whose operations are characterized by high stress loading and fatigue failure resulting in high maintenance costs. The operating environment and the stress fields on the boom must continually be monitored to avoid random fatigue failure to achieve reliability, longevity and economic usage. In this paper, the authors develop dynamic models for real-time stress monitoring using a combination of flexible and rigid body approach. A virtual prototype simulator is developed to simulate the cable shovel excavation in oil sands and to examine the motion, stress and local deformation of the boom. The P&H 4100A cable shovel, deployed in the Athabasca oil sands formation, is used to examine the cable shovel boom durability using stress fields simulation. The results show that high stresses occur at regions around the joint between the upper body and the boom, resulting in large deformations. In hard formations, the results show that the stress fields in this region exceed the Von Mises yield strength of steel used in making the shovel boom components. The results also show that the FE nodes of 178, 168, 120, 63, 127 and 84 for 10MPa modulus of elasticity and 127, 61, 126, 45, 60 and 39 nodes for 20MPa modulus of elasticity are the highly stressed nodes with high degree of boom deformation and fatigue failure. The study provides a solid foundation for further study of failure life analysis of the cable shovel components. [Copyright &y& Elsevier]

Hydraulic shovels are large-capacity equipment for excavating and loading dump trucks in constrained surface mining environments. Kinematics simulation of such equipment allows mine planning engineers to plan, design and control their spatial environments to achieve operating safety and efficiency. In this study, a hydraulic shovel was modelled as a mechanical manipulator with five degrees of freedom comprising the crawler, upper, boom, stick, bucket and bucket door components. The model was captured in a schematic diagram consisting of a six-bar linkage using the symbolic notation of Denavit and Hartenberg (Ho and Sriwattanathmma 1989). Homogeneous transformation matrices were used to capture the spatial configuration between adjacent links. The forward kinematics method was used to formulate the kinematics equations by attaching Cartesian coordinates to the schematic shovel diagram. Based on the kinematics model, a 3D virtual prototype of the hydraulic shovel was built in the Automatic Dynamic Analysis of Mechanical Systems (ADAMS) environment to simulate the motions of the hydraulic shovel with selected time steps. The simulator was validated using real-world data with animation and numerical analysis of the digging, swinging and dumping motions of the shovel machinery. The superimposed display of the deployment of the hydraulic shovel in three phases allows a detailed motion examination of the system. The numerical results of linear and angular displacements of the bucket tip and bucket door can be used to analyse the kinematics motion of the hydraulic shovel for its optimization. This simulator provides a solid foundation for further dynamics modelling and dynamic hydraulic shovel performance studies. [ABSTRACT FROM AUTHOR]