ADAMS Simulation Research Articles

Shift Quality Amelioration of EV with AMT by Speed Regulation

Due to torque interruption and clutch friction of Automated Manual Transmissions (AMT) during gear shift, the shift quality is not as positive as other kinds of transmissions, several ways to improve shift quality such as reduce shift time have been researched. During the gear shift process in AMT, new gear speed needs to be regulated as gear ratio changes. In this paper, the research topic is concerning gear shift process of an AMT of electric vehicles, the influence of the speed difference between new gear and synchronizer on gear shift time is studied. Powertrain model of the electric vehicles with AMT is built in ADAMS and several simulations are conducted. Simulation results demonstrate that by controlling the speed difference between new gear and synchronizer in a positive small range from 0rpm to +10rpm with the shift force at 200N, shifting synchronizer can be engaged in a short time. In addition, results also demonstrate that within small speed difference range, the existence of synchronizer ring has little effect on gear shift performance, which illustrates that the structure of AMT on electric vehicles can be simplified.

Inertial force balance and ADAMS simulation of the oscillating sieve and return pan of a rice combine harvester

Inertial force balance and ADAMS simulation of the oscillating sieve and return pan of a rice combine harvester

Kinematics simulation analysis and trajectory planning of a moving robot based on ADAMS

The study of kinematics modeling and simulation of industrial robots is the basis of robot development and optimization. According to the configuration characteristics of a moving robot, the coordinate system and the kinematics equation of the connecting rod are established based on the DH coordinate transformation method. The kinematics positive solution problem is solved in detail. The moving robot is established by the joint simulation of Solid works and ADAMS The motion model of the moving robot is verified by the kinematic analysis, and the displacement and angle curve of the end point are obtained. The rationality of the kinematics model of the moving robot is verified. The trajectory planning of the moving robot is carried out according to the actual situation, the results show that the moving robot is running smoothly and meets the requirements, which provides an important basis for the subsequent control research.

Mechanism design and kinematic analysis of a robotic manipulator driven by joints with two degrees of freedom (DOF)

PurposeThis paper aims to introduce a new design concept for robotic manipulator driven by the special two degrees of freedom (DOF) joints. Joint as a basic but essential component of the robotic manipulator is analysed emphatically.Design/methodology/approachThe proposed robotic manipulator consists of several two-DOF joints and a rotary joint. Each of the two-DOF joints consists of a cylinder pairs driven by two DC motors and a universal joint (U-joint). Both kinematics of the robotic manipulator and the two-DOF joint are analysed. The influence to output ability of the joint in terms of the scale effect of the inclined plane is analysed in ADAMS simulation software. The contrast between the general and the proposed two-DOF joint is also studied. Finally, a physical prototype of the two-DOF joint is developed for experiments.FindingsThe kinematic analysis indicates that the joint can achieve omnidirectional deflection motion at a range of ±50° and the robotic manipulator can reach a similar workspace in comparison to the general robotic manipulator. Based on the kinematic analysis, two special motion modes are proposed to endow the two-DOF joint with better motion capabilities. The contrast simulation results between the general and the proposed two-DOF joints suggest that the proposed joint can perform better in the output ability. The experimental results verify the kinematic analysis and motion ability of the proposed two-DOF joint.Originality/valueA new design concept of a robotic manipulator has been presented and verified. The complete kinematic analysis of a special two-DOF joint and a seven-DOF robotic manipulator have been resolved and verified. Compared with the general two-DOF joint, the proposed two-DOF joint can perform better in output ability.

Research and simulation of anti - rollover technology of harvester

The structural characteristics of our country’s corn harvester are narrow-track, high centroid and existence of eccentric distance, so rollover accident is easily to occur when going up and down the hills mountainous and hilly regions for complex terrain. In the previous paper, we introduced the Hydro-Pneumatic Suspension to prevent the roller of the harvester, and took ADAMS simulation on the left and right roller, and obtained that the use of Hydro-Pneumatic Suspension can improve the side angle of the harvester for 5°. At the same time, we continue to use the Hydro-Pneumatic Suspension as the key part of the anti-roller system of the harvester. In the uphill and downhill case of the harvester, we respectively simulated the anti-roller performance on the traditional harvester and the harvester installing the Hydro-Pneumatic Suspension. Finally, we got that the anti-roller angle of the harvester installed Hydro-Pneumatic Suspension is obviously higher than the traditional harvester, which indicates that the anti-rollover performance of the harvester installed Hydro-Pneumatic Suspension is better than the traditional harvester. The data obtained from this experiment will provide technical support for the following structure optimization of the harvester.

Research on the Influence of Straddle-Type Monorail\u2019s Pantograph Head Parameter on Power Collection Quality

At present, the coupling relationship between the pantograph and catenary is not ideal for straddle-type monorail. The power collection quality is poor, and the wear of the contact strip of a pantograph is uneven. Therefore, the key problem of coupling relation between the pantograph and catenary is the dynamics of a pantograph–catenary system. This paper analyzed the modal of catenary through simulation with finite element model and the vibration modal of pantograph multi-rigid-body dynamic model by simulation in multi-body danamics software ADAMS. A rigid-flexible coupling dynamic model of pantograph–catenary system is established. Finally, extensive research has been made on the influence of pantograph head parameters on the power collection quality.

Attitude Control Equation of the Two-wheeled Self-balancing Electric Vehicle

In order to get control of motion characteristics of the two-wheeled self-balancing vehicle, based on the dynamic modeling and the correction of ADAMS simulation, a mathematical model of body posture of body angle and wheel driving torque which contains a correction factor was build. The simulation results of the model show that the horizontal velocity of the center of gravity of the swing rob and the wheel center were almost coincides entirely with each other both on model calculation and ADAMS simulation, so the body of the vehicle could keep relatively static on horizontal direction under the control of this model. The position changing value of swinging rob was always less than 1mm, Thus it proved that the modified equation was proper and could be used to control the motion of the two-wheeled self-balancing electronic vehicle.

Dynamics analysis and simulation verification of a novel knee joint exoskeleton

A novel knee joint exoskeleton, is designed in this paper, including the mechanical structure and hydraulic damper. To determine the spring parameters of knee joint exoskeleton and verify its effectiveness, we conduct the following studies. Firstly, forward kinematics analysis of the swing phase is obtained and Lagrange dynamics analysis is carried out. Secondly, the 3D model of exoskeleton is set up and ADAMS simulation is conducted. Then the spring parameters of knee joint exoskeleton are selected, including the spring force, the spring stiffness coefficient and the spring expansion, according to the simulation results. Finally, there are three sets of moments on the non-wearable side, the moments resulted from ADAMS simulations, the moments from the CGA (Clinical gait analysis) and the moments calculated from the Lagrange equation are compared, results show they are in good agreement. The effectiveness of the ADAMS simulation proves that the parameters of the hydraulic damper can meet the actual requirements. The simulation analysis of the exoskeleton provides important parameters for the manufacture and it also provides theoretical basis for the later control theory.

Lateral vibration behavior analysis and TLD vibration absorption design of the soft yoke single-point mooring system

Mooring system is the key equipment of FPSO safe operation. The soft yoke mooring system is regarded as one of the best shallow water mooring strategies and widely applied to the oil exploitation in the Bohai Bay in China and the Gulf of Mexico. Based on the analysis of numerous monitoring data obtained by the prototype monitoring system of one FPSO in the Bohai Bay, the on-site lateral vibration behaviors found on the site of the soft yoke subject to wave load were analyzed. ADAMS simulation and model experiment were utilized to analyze the soft yoke lateral vibration and it was determined that lateral vibration was resonance behaviors caused by wave excitation. On the basis of the soft yoke longitudinal restoring force being guaranteed, a TLD-based vibration damper system was constructed and the vibration reduction experiments with multi-tank space and multi-load conditions were developed. The experimental results demonstrated that the proposed TLD vibration reduction system can effectively reduce lateral vibration of soft yoke structures.

Design of Steering Suspension Guide Device with Large AngleBased on ADAMS Simulation and Linear Regression Analysis

Design of Steering Suspension Guide Device with Large AngleBased on ADAMS Simulation and Linear Regression Analysis

Truck Rollover Simulation on Curved Section of Freeway Based on ADAMS

Truck’s rollover is one of the most single truck accident forms happened on freeway. This paper took three axis Hercules truck of Dongfeng series as the prototype, and used the ADAMS simulation software to build the rigid-flexible coupling truck vehicle model of 529 Gruebler count. The 3D coordinate of road center, road width, road super-elevation, left and right side friction co-efficient of road were used to achieve the building of road model. The road center coordinates’ tracking, the input of steering wheel angle and running speed’s controlling were used to implement the driver model’s building. Then four simulation experiment conditions, including the road conditions, traffic conditions, input conditions of steering wheel angle and the feature points of non-measured section, were set up and the rollover simulation experiment of truck were carried on. The tire vertical force values were selected as quantitative indicators to estimate rollover accidents, and mathematical statistics and numerical interpolation method were used to calculate the critical rollover safety driving speed threshold for truck of different mass center height on different ultra- high curved section, which was of great significance for understanding the mechanism of the rollover accident and putting forward the truck speed limit standard.

A General Method on Establishing Fatigue Test Specification of Torsion Beam Rear Axle

A general method is proposed for establishing the fatigue test specification of torsion beam rear axle (TBRA) in the car. The main characteristic parameters of entire vehicle are analyzed by using ADAMS simulation, to study which vehicle parameter is associated with the load, and figured out the relationship between the testing load and the key vehicle parameter based on the existing test specifications. An illustrative comparison in theoretical fatigue lifetime of the TBRA is presented to demonstrate the feasibility and effectiveness of the proposed fatigue test specification. The proposed method of establishing fatigue test specification can provide a reference for durability evaluation of chassis components and help suppliers achieve the synchronous development with OEMs.

Kinematics Simulation of a Hybrid Leg Structure of a Novel Quadruped Robot

This paper presents a quadruped robot of novel structure, which has four hybrid legs. A research on the hybrid legs kinematics of the quadruped was conducted to analyse the motion characteristics of it. First, the coordinated systems were established according to the characteristics of spatial mechanism. And by using the coordinate transformation method, kinematics reverse solution was obtained. Several typical trajectories have been planned include rotations around X、Y、Z axes and leg-lift action and the drive angle data were calculated for each movement based on MATLAB. The analysis and simulation of the mechanism were made to verify the kinematics reverse solution based on the ADAMS simulation model. The simulation results proved that the above kinematics reverse solution is correct. In addition, the dynamic characteristics of the driving force were obtained to provide guidance for selection of the motor.

Research on the impact of dynamic performance of Metro gear transmission system caused by track spectrum excitation

In order to explore the influence of track irregularity on the gear transmission system of urban rail transit vehicles, we built the Metro helical gears model of the bend-torsion-axes, which considered the time-varying meshing stiffness, gear meshing error, backlash nonlinearity etc. Besides, the track spectrum excitation was considered in the system for the first time, used the variable step forth order Runge-Kutta algorithm solve the model, obtained the gear system dynamic response diagrams, analysed the system stability and dynamic transfer error (DTE) of the gear system under the track spectrum excitation with the dynamic model and the ADAMS simulation. The result show that the single periodic motion of the system is changed into the quasi periodic motion with the influence of track spectrum excitation, and the DTE was increased. The paper lays a theoretical foundation for the research of the Metro gear transmission system. [Received 16 July 2016; Revised 27 October 2016; Accepted 16 November 2016]

Research on the impact of dynamic performance of Metro gear transmission system caused by track spectrum excitation

In order to explore the influence of track irregularity on the gear transmission system of urban rail transit vehicles, we built the Metro helical gears model of the bend-torsion-axes, which considered the time-varying meshing stiffness, gear meshing error, backlash nonlinearity etc. Besides, the track spectrum excitation was considered in the system for the first time, used the variable step forth order Runge-Kutta algorithm solve the model, obtained the gear system dynamic response diagrams, analysed the system stability and dynamic transfer error (DTE) of the gear system under the track spectrum excitation with the dynamic model and the ADAMS simulation. The result show that the single periodic motion of the system is changed into the quasi periodic motion with the influence of track spectrum excitation, and the DTE was increased. The paper lays a theoretical foundation for the research of the Metro gear transmission system. [Received 16 July 2016; Revised 27 October 2016; Accepted 16 November 2016]

The Capturing of Space Debris with a Spaceborne Multi-fingered Gripper

With the massive launching of spacecraft, more and more space debris are making the low Earth orbit (LEO) much more crowded which seriously affects the normal flight of other spacecrafts. Space debris removal has become a very urgent issue concerned by numerous countries. In this paper, using SwissCube as a target, the capturing of space debris with a spaceborne four-fingered gripper was studied in order to obtain the key factors that affect the capturing effect. The contact state between the gripper fingers and SwissCube was described using a defined contact matrix. The law of momentum conservation was used to model the motion variations of the gripper and SwissCube before and after the capturing process. A zero-gravity simulation environment was built using ADAMS software. Two typical kinds of capturing processes were simulated considering different stiffness of fingers and different friction conditions between fingers and SwissCube. Comparisons between results obtained with the law of momentum conservation and those from ADAMS simulation show that the theoretical calculations and simulation results are consistent. In addition, through analyzing the capturing process, a valuable finding was obtained that the contact friction and finger flexibility are two very important factors that affect the capturing result.

Adaptability to stratum characteristics for layout of thrust system in tunneling machines based on variation coefficient

This study aims to investigate the characteristics of adaptability to stratum for thrust system in tunneling machines in composite stratum. Initially, variation coefficient thrust model has been constructed on the basis of a mechanical model. By analyzing the variation coefficient thrust model, the variation coefficient surface can be discovered. Second, by analyzing the relationship between spaces of variation coefficient surface and adaptability to compound ground, the variation coefficient surface family which indicates the adaptive ability to stratum conditions for pushing system has been discovered. Eventually, applying variation coefficient adaptability model to the driving system of shield machine in engineering applications, adaptability for two layouts with the same number of hydraulic cylinders in thrust system has been discussed in detail through comparison of numerical analysis and simulation in ADAMS. The results could provide theoretical foundation and support for the design of an adaptability thrust system under composite stratum.

Analytical Energetic Approach for Predictive Generation of Dynamic Biped Walking - Use of Average Energies

This paper presents a control strategy for biped robot walking based on energetic approach. Our aim is to be able, in real time, to predict the length of the next step that the biped should execute to ensure its desired speed. According to known (measured) state in the previous step the proposed algorithm will establish the desired global parameters (i.e. the biped average velocity). The new approach presented in this paper benefits from a formulation of energy exchanges using the average values of all energies contributing during dynamic bipedal walking. We develop a model that takes into account kinetic and propulsion (provided by the rear leg) energies as well as the energy lost during the impact of the front leg. We introduce a recursive formulation in order to predict the energy behavior of the biped robot during its walk. Analytical and concise expression suitable for real-time application was developed. We show that the same formulation is convenient for both flat terrain and crossing over obstacles in the sagittal plane. Hence, we are able, in both cases, to determine the next step length required to ensure the desired average velocity. We validate the proposed approach through an ADAMS simulation of a planar robot in the sagittal plane. The obtained results show the efficiency of this promising approach.

Coupled vibrations of rope-guided hoisting system with tension difference between two guiding ropes

The flexibility of the guiding rope and the tension difference between two guiding ropes cause the lateral and torsional vibrations of the hoisting conveyance in the rope-guided hoisting system, respectively, which are theoretically investigated with two different cases in this paper. The assumed modes method is used to discretize the hoisting rope and two guiding ropes, and Lagrange equations of the first kind is adopted to derive the equations of motion, while the geometric matching conditions at the interfaces of the ropes are accounted for by the Lagrangian multiplier. Considering all the geometric matching conditions are approximately linear, the differential algebraic equations are transformed to a system of ordinary differential equations. The current method can obtain not only the accurate lateral displacements of two guiding ropes, but also the constraint forces between the hoisting conveyance and two guiding ropes. Further, the current method is verified by the ADAMS simulation. Finally, the effects of various parameters on the lateral and torsional vibrations of the hoisting conveyance are analyzed and results indicate that the appropriate tension difference and distance difference could decrease the maximum lateral displacement, which is useful to design super deep rope-guided hoisting system for the decrease of the vibration.

Dynamic responses of cable-driven parallel sinking platform

ABSTRACTThe dynamic responses of cable-driven parallel sinking platform are investigated considering the longitudinal–torsional coupled characteristics of the cable. The dynamic equations of the system are derived through the Lagrange equations, and the geometric matching conditions and the constraint forces at the interfaces between the cables and the platform have also been considered in the equations through Lagrangian multipliers. By neglecting the slack state of the cable, the numerical results of the mathematical model are obtained through Newmark-beta method after transforming the derived differential algebraic equations (DAEs) to a system of ordinary differential equations (ODEs). An ADAMS simulation is carried out, and the ADAMS simulation results agree well with the results obtained through Newmark-beta method. The results have shown that the lateral characteristics of the cables have a great effect on the torsional vibration of the platform, and by arranging the cables correctly will help to reduce the rotation of the platform.