This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller fo...This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller for a laser beam steering system.The proposed technique uses the ADRC philosophy to lump disturbances and model uncertainties into a total disturbance.Then,the total disturbance is estimated via a discrete extended state disturbance observer(ESO),and it is used to(1)handle the system constraints in a quadratic optimization problem and(2)injected as a feedforward term to the plant to reject the total disturbance,together with the feedback term obtained by the MPC.The main advantage of the proposed approach is that the MPC is designed based on a straightforward integrator-chain model such that a simple convex optimization problem is performed.Several experiments show the real-time closed-loop performance regarding trajectory tracking and disturbance rejection.Owing to simplicity,the self-contained approach MPC+ESO becomes a Frugal MPC,which is computationally economical,adaptable,efficient,resilient,and suitable for applications where on-board computational resources are limited.展开更多
The enhancement of vehicle handling stability and maneuverability through active and independent rear wheels control is presented. Firstly, the configuration of four-wheel independent steering prototype vehide is intr...The enhancement of vehicle handling stability and maneuverability through active and independent rear wheels control is presented. Firstly, the configuration of four-wheel independent steering prototype vehide is introduced briefly. Then the concrete overall design of the electronic controllers of four wheel independent steering system （4WIS） is formulated in details. Under the control strategy of zero sideslip angle at mass center, the mathematical model of 4WIS is established to deduce the equations of separated rear wheel steering angles. According to these equations, simulation analysis for 4WIS vehicle performances is finished to show that 4WIS vehicle can improve the maneuverability greatly at low speed and increase the handling stability at high speed. Finally, the road test of 4WIS vehide has performed to verify the correctness of simulation and show that compared with the conventional four wheel steering （4WS） vehicle, the 4WIS vehicle not only improves the kinematical harmony but also decreases steering resistance and lighten abrasion of tires.展开更多
Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and disc...Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously by using bladder accumulator, the hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle generates vibration at the initial stage under the normal steering condition of pulse input, and its static response time is 0.25 s shorter than that without bladder accumulator. Under the normal steering working condition, the capacity of steering accumulator for absorbing pulse is directly proportional to the cross section area of connecting pipeline, and inversely proportional to the length of connecting pipeline. At the same time, the precharge pressure of nitrogen in steering accumulator should be 60%80% of the rated minimum working pressure of hydraulic power steering system. Under the abnormal steering working condition, the steering cylinder piston may obtain higher motion velocity, and the dynamic response velocity of hydraulic power steering system can be increased by reducing the pressure drop of hydraulic pipelines between the accumulator and steering cylinder and by increasing the rated pressure of hydraulic power steering system, but the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle have nothing to do with the precharge pressure of nitrogen in steering accumulator.展开更多
Load-sensing steering systems for articulated loaders are prone to large pressure shocks and oscillations during steering operations,affecting the system stability.An optimized structure of the redirector with bypass ...Load-sensing steering systems for articulated loaders are prone to large pressure shocks and oscillations during steering operations,affecting the system stability.An optimized structure of the redirector with bypass damping is proposed to improve this phenomenon.In this structure,orifices and throttle grooves are added to the traditional redirector.To control the steering load and working conditions,the steering load of the loader is replaced by a pressure regulating valve.Simulation and experimental results reveal that the redirector with bypass damping has better load-sensing characteristics than the traditional redirector.The peak output pressure shock caused by the load unit step signal decreases from 6.50 to 5.64 MPa,which means the pressure oscillation of the hydraulic system is reduced by 13.4%.The pressure fluctuation time can be reduced from 2.09 to 1.6 s,with a decrease rate of 23.4%.The output pressure oscillation decays swiftly,and the smoothness of the steering operation is improved significantly.展开更多
Water-jet propulsion is a widely applied ship propulsion technology.Its steering control system has an important impact on manoeuvre performance.In this paper,transfer function model is firstly established on the basi...Water-jet propulsion is a widely applied ship propulsion technology.Its steering control system has an important impact on manoeuvre performance.In this paper,transfer function model is firstly established on the basis of mechanism analysis of water-jet steering system.Then,by considering the variability of model parameters and input constraints in practical operation,a model predictive controller is designed for steering system control.Subsequently,model based disturbance observer is employed in an attempt to reject environmental disturbances.The performance of the proposed model predictive control (MPC) scheme for a particular steering system is compared with that of conventional proportional integral derivative (PID) control strategy.Simulation results demonstrate that the proposed model predictive controller outperforms conventional PID controller,particularly in robustness,response delay and tracking accuracy.展开更多
With the development and improvement of the hydraulic steering system,the articulated steering system became the research focus of numerous domestic and foreign scholars.The full hydraulic steering system with a compa...With the development and improvement of the hydraulic steering system,the articulated steering system became the research focus of numerous domestic and foreign scholars.The full hydraulic steering system with a compact structure and ease of operation,is widely used in articulated steering mode.Furthermore,its performance can directly impact the steering sensitivity and stability.This paper studies the working principle and actual structure of the priority valve and the steering control valve,which are very important.By setting up a mathematic model,the system’s load-sensing characteristics and the impact of steering control valve bypass throttle damping on steering stability can be analyzed.The Hydraulic Components Design(HCD)model was established for the hydraulic part of this system.It is proved that the model can reflect the system’s actual properties by comparing simulation and experimental results.The dynamic model is based on its actual prototype parameters by taking the tire and ground forces into account.The steering process’s dynamic characteristics are co-simulated in the 1D+3D system model by combining AMESim and Virtual.Lab Motion.The simulation results show that the system’s load-sensing characteristics ensure the sensitivity of the steering operation,and the bypass throttle damping has significantly improved the operation stability and lowered down the cylinder pressure fluctuations.This can improve the system performance by appropriate optimization.展开更多
In view of the large energy loss problem in the traditional full hydraulic steering system,a scheme of replacing the ordinary pump with the priority valve with the load sensitive variable pump is proposed to make the ...In view of the large energy loss problem in the traditional full hydraulic steering system,a scheme of replacing the ordinary pump with the priority valve with the load sensitive variable pump is proposed to make the variable pump provide the corresponding flow rate according to the needs of the steering system to achieve the purpose of energy saving.Through the establishment of the system AMESim simulation model,the data comparison shows that the energy loss of the load sensitive variable steering system is significantly reduced relative to the traditional full hydraulic steering system.展开更多
Push-the-bit rotary steering system can greatly improve the rate of penetration(ROP),hole conditions and hole extension length and represents the development direction of modern steering drilling technology.In order t...Push-the-bit rotary steering system can greatly improve the rate of penetration(ROP),hole conditions and hole extension length and represents the development direction of modern steering drilling technology.In order to accurately predict and evaluate the build-up rate of pushthe-bit rotary steering system(RSS),this paper establishes the drilling trajectory prediction model and the calculation methods of‘limit build-up rate’and‘corrected build-up rate’for push-the-bit rotary steering system by comprehensively considering the interaction between thruster and sidewall and between bit and formation,the structure of RSS and other influential factors based on the mechanical model of the conventional RSS.Then,the influence mechanisms on the build-up rate are revealed from the aspects of‘leverage effect’,‘pendulum effect’and‘thrust effect’.Finally,the influence laws of thrust force,weight on bit(WOB),borehole inclination angle,bit and formation anisotropy on the build-up rate are analyzed.And the following research results are obtained.First,the build-up rate of RSS is the comprehensive result of various effects,among which‘thrust effect’plays a dominant role and‘leverage effect’and‘pendulum effect’play secondary roles.Second,as for the push-thebit rotary steering system,the proportion of‘leverage effect’increases,the proportion of‘thrust effect’decreases and the build-up rate declines with the increase of WOB.Third,the build-up rate is in a close relationship with structural parameters,thrust force,bit properties and drilling parameters of RSS.In conclusion,the research results can provide an important theoretical basis for the prediction of build-up rate of push-thebit rotary steering system and the optimization of RSS structure.展开更多
With the economic globalization, the development of new technological revolution and the adjustment of industrial structure, the international trend of truck production are becoming more and more obvious. Mastering th...With the economic globalization, the development of new technological revolution and the adjustment of industrial structure, the international trend of truck production are becoming more and more obvious. Mastering the basic knowledge of truck structure, understanding the basic principles of truck subsystem operation, being familiar with the functions of various components in the system and having the ability to solve truck failures independently are the basic qualities that every driver should have. The analysis of the principle and troubleshooting methods of truck steering system is helpful to improve the drivers ability to deal with emergency accidents, and also provides a powerful reference for the research and development innovation of steering system.展开更多
The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering （EPS） system. Bad tracking performance will cause assistant torque delay, and make road ...The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering （EPS） system. Bad tracking performance will cause assistant torque delay, and make road feeling bad, and is influenced by the input steering torque and system measuring noise. However the existing methods have some shortages on system＇s robust dynamic performance and robust stability. The mixed H2/H∞ strategy for recirculating ball-type EPS system in a pure electric bus is proposed, and vehicle dynamic model of the system is established. Due to the existence of system model uncertainty, disturbance signals, sensor noises and the demand of system dynamic performance, the indexes of robust performance and road feeling for drivers are defined as the appraisal control objectives. The H∞ method is introduced to design the H∞ controller, and the H2 method is applied to optimize the H∞ controller, thus the mixed H2/H∞ controller is designed. The response of EPS system to the motor current command with amplitude of 20 A, the road disturbance with amplitude of 500 N and the sensor random noise with the amplitude of 1 A is simulated. The simulation results show that the recirculating ball-type EPS system with the mixed H2/H∞ controller can attenuate the random noises and disturbances and track the boost curve well, so the mixed H2/H∞ controller can improve the system＇s robust performance and dynamic performance. For the purpose of verifying the performance of the designed control strategy, the motor current tracking performance ground tests are conducted with step response input of the steering wheel, double-lane steering test and lemniscate steering test, respectively. The tests show that the mixed H2/H∞ controller for the recirculating ball-type EPS system of pure electric bus is feasible. The designed controller can solve the robust performance and robust stability of the system, thus improve the tracking performance of the EPS system and provide satisfied road feeling for the drivers.展开更多
The dynamic model of a novel electric power steering （EPS） system integrated with active front steering function （the novel EPS system） is built. The concepts and quantitative expressions of the steering road feel...The dynamic model of a novel electric power steering （EPS） system integrated with active front steering function （the novel EPS system） is built. The concepts and quantitative expressions of the steering road feel, steering sensibility, and steering operation stability are introduced. Based on quality engineering theory, the optimization algorithm is proposed by integrating the Monte Carlo descriptive sampling, elitist non-dominated sorting genetic algorithm （NSGA-II） and 6-sigma design method. With the steering road feel and the steering portability as optimization targets, the system parameters are optimized by the proposed optimization algorithm. The simulation results show that the system optimized based on quality engineering theory can improve the steering road feel, guarantee steering stability and steering portability and thus provide a theoretical basis for the design and optimization of the novel electric power steering system.展开更多
Because the general object of ship steering control system is singular, the state Of rudder force and the state of disturbance are separated, and the generalized yaw output disturhance is obtained. Furthermore, singul...Because the general object of ship steering control system is singular, the state Of rudder force and the state of disturbance are separated, and the generalized yaw output disturhance is obtained. Furthermore, singular system control problem of ship yaw and sway coupled system is transferred into nonsingular standard control problem. Then according to the linear fractional denoting algorithm of the rational function parameter perturbation system, the Linear Fractional Transform （LFT） model of yaw and sway coupled motion is solved, which is used to design the ship steering robust control system. For the ship steering system with the uncertain parameters, the robust control law is designed based on H^∞ μ-synthesis. And the robust performance of the system is analyzed and the simulation validation is made. Simulation results show that the designed control system has excellent control effect and robustness.展开更多
A novel active steering system with force and displacement coupled control(the novel AFS system) was introduced,which has functions of both the active steering and electric power steering.Based on the model of the nov...A novel active steering system with force and displacement coupled control(the novel AFS system) was introduced,which has functions of both the active steering and electric power steering.Based on the model of the novel AFS system and the vehicle three-degree of freedom system,the concept and quantitative formulas of the novel AFS system steering performance were proposed.The steering road feel and steering portability were set as the optimizing targets with the steering stability and steering portability as the constraint conditions.According to the features of constrained optimization of multi-variable function,a multi-variable genetic algorithm for the system parameter optimization was designed.The simulation results show that based on parametric optimization of the multi-objective genetic algorithm,the novel AFS system can improve the steering road feel,steering portability and steering stability,thus the optimization method can provide a theoretical basis for the design and optimization of the novel AFS system.展开更多
Pressure ripples in electric power steering （EPS） systems can be caused by the phase lag between the driver s steering torque and steer angle, the nonlinear frictions, and the disturbances from road and sensor noise...Pressure ripples in electric power steering （EPS） systems can be caused by the phase lag between the driver s steering torque and steer angle, the nonlinear frictions, and the disturbances from road and sensor noise especially during high-frequency maneuvers. This paper investigates the use of the robust fuzzy control method for actively reducing pressure ripples for EPS systems. Remarkable progress on steering maneuverability is achieved. The EPS dynamics is described with an eight-order nonlinear state-space model and approximated by a Takagi-Sugeno （T-S） fuzzy model with time-varying delays and external disturbances. A stabilization approach is then presented for nonlinear time-delay systems through fuzzy state feedback controller in parallel distributed compensation （PDC） structure. The closed-loop stability conditions of EPS system with the fuzzy controller are parameterized in terms of the linear matrix inequality （LMI） problem. Simulations and experiments using the proposed robust fuzzy controller and traditional PID controller have been carried out for EPS systems. Both the simulation and experiment results show that the proposed fuzzy controller can reduce the torque ripples and allow us to have a good steering feeling and stable driving.展开更多
The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the develo...The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.展开更多
In this paper, the performance of a column-type electric power steering （EPS） system and vehicle has been studied and a detailed mathematical model for the system has been established. Based on the mathematic model ...In this paper, the performance of a column-type electric power steering （EPS） system and vehicle has been studied and a detailed mathematical model for the system has been established. Based on the mathematic model of the optimization design for steering feel, the parameters of the EPS system and vehicle on steering performance have been investigated. Moreover, the effects of the parameters on system stability have been analyzed and compared by the method of absolute sensitivity and the results are given in the end.展开更多
A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of ...A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of simpled steering resistance force and the relationship between assist gain and vehicle speed are presented for the first time. Assist character is found based on the parameters of a sedan at last. This assist character is fit for the control rule of the EPS system through analyzing this character. The assist character figure offers reference for system design and control. Furthermore, this research method has generality for assist character of different kinds of vehicles.展开更多
As all-electric aircraft has many advantages,an aircraft nose wheel steering system would be developed to the all-electric direction.Concerning the control demand of the nose wheel steering system,based on the basic p...As all-electric aircraft has many advantages,an aircraft nose wheel steering system would be developed to the all-electric direction.Concerning the control demand of the nose wheel steering system,based on the basic principles of nose wheel steering system and the design technique of mechanotronics,an all-electric aircraft nose wheel steering system,composed of a nose wheel steering mechanism of two worm gear and a control servo system of fly-by-wire with both steering and anti-shimmy functions is designed to meet the demand for operation control in the nose wheel steering system.Then,based on the LMS-AMESim software,the simulation model of the system is established to simulate the dynamics for the verification of its steering function.The simulation results indicate that the nose wheel steering system is reasonable,and can meet the requirements of the general project.Furthermore,the prototypes of the steering mechanism and control system are studied to validate the design,and the steering test bench is prepared to test the designed system.The test results,such as steer angle,rotate speed of motor are analyzed in details and compared with the theoretical results.The analysis and comparison results show that the design is reasonable and the property of the prototype can achieve the design objectives.展开更多
A differential steering system is presented for electric vehicle with motorized wheels and a dynamic model of three-freedom car is built.Based on these models,the quantitative expressions of the road feel,sensitivity,...A differential steering system is presented for electric vehicle with motorized wheels and a dynamic model of three-freedom car is built.Based on these models,the quantitative expressions of the road feel,sensitivity,and operation stability of the steering are derived.Then,according to the features of multi-constrained optimization of multi-objective function,a multi-island genetic algorithm(MIGA)is designed.Taking the road feel and the sensitivity of the steering as optimization objectives and the operation stability of the steering as a constraint,the system parameters are optimized.The simulation results show that the system optimized with MIGA can improve the steering road feel,and guarantee the operation stability and steering sensibility.展开更多
With the gradual development of national economy, the mining task of coal mining industry has become more and more heavy. The demand for the mine wide body dump truck is also surging, promoting the rapid progress and ...With the gradual development of national economy, the mining task of coal mining industry has become more and more heavy. The demand for the mine wide body dump truck is also surging, promoting the rapid progress and development of the mine wide-body mine dump truck. However, the current hydraulic steering system still has high failure rate, vehicle steering system involves the safety of the driver, so people attach great importance to it. It is an important way to find and judge the possible failure points in advance and solve them pertinently. In this paper, the failure of hydraulic steering system is analyzed and the corresponding solutions are put forward.展开更多
基金support through his Master scholarshipThe Vicerrectoría de Investigación y Estudios de Posgrado(VIEP-BUAP)partially funded this work under grant number 00593-PV/2025.
文摘This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller for a laser beam steering system.The proposed technique uses the ADRC philosophy to lump disturbances and model uncertainties into a total disturbance.Then,the total disturbance is estimated via a discrete extended state disturbance observer(ESO),and it is used to(1)handle the system constraints in a quadratic optimization problem and(2)injected as a feedforward term to the plant to reject the total disturbance,together with the feedback term obtained by the MPC.The main advantage of the proposed approach is that the MPC is designed based on a straightforward integrator-chain model such that a simple convex optimization problem is performed.Several experiments show the real-time closed-loop performance regarding trajectory tracking and disturbance rejection.Owing to simplicity,the self-contained approach MPC+ESO becomes a Frugal MPC,which is computationally economical,adaptable,efficient,resilient,and suitable for applications where on-board computational resources are limited.
文摘The enhancement of vehicle handling stability and maneuverability through active and independent rear wheels control is presented. Firstly, the configuration of four-wheel independent steering prototype vehide is introduced briefly. Then the concrete overall design of the electronic controllers of four wheel independent steering system （4WIS） is formulated in details. Under the control strategy of zero sideslip angle at mass center, the mathematical model of 4WIS is established to deduce the equations of separated rear wheel steering angles. According to these equations, simulation analysis for 4WIS vehicle performances is finished to show that 4WIS vehicle can improve the maneuverability greatly at low speed and increase the handling stability at high speed. Finally, the road test of 4WIS vehide has performed to verify the correctness of simulation and show that compared with the conventional four wheel steering （4WS） vehicle, the 4WIS vehicle not only improves the kinematical harmony but also decreases steering resistance and lighten abrasion of tires.
文摘Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously by using bladder accumulator, the hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle generates vibration at the initial stage under the normal steering condition of pulse input, and its static response time is 0.25 s shorter than that without bladder accumulator. Under the normal steering working condition, the capacity of steering accumulator for absorbing pulse is directly proportional to the cross section area of connecting pipeline, and inversely proportional to the length of connecting pipeline. At the same time, the precharge pressure of nitrogen in steering accumulator should be 60%80% of the rated minimum working pressure of hydraulic power steering system. Under the abnormal steering working condition, the steering cylinder piston may obtain higher motion velocity, and the dynamic response velocity of hydraulic power steering system can be increased by reducing the pressure drop of hydraulic pipelines between the accumulator and steering cylinder and by increasing the rated pressure of hydraulic power steering system, but the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle have nothing to do with the precharge pressure of nitrogen in steering accumulator.
基金Supported by National Key Research and Development Program of China(Grant No.2018YFB2000900).
文摘Load-sensing steering systems for articulated loaders are prone to large pressure shocks and oscillations during steering operations,affecting the system stability.An optimized structure of the redirector with bypass damping is proposed to improve this phenomenon.In this structure,orifices and throttle grooves are added to the traditional redirector.To control the steering load and working conditions,the steering load of the loader is replaced by a pressure regulating valve.Simulation and experimental results reveal that the redirector with bypass damping has better load-sensing characteristics than the traditional redirector.The peak output pressure shock caused by the load unit step signal decreases from 6.50 to 5.64 MPa,which means the pressure oscillation of the hydraulic system is reduced by 13.4%.The pressure fluctuation time can be reduced from 2.09 to 1.6 s,with a decrease rate of 23.4%.The output pressure oscillation decays swiftly,and the smoothness of the steering operation is improved significantly.
基金the Open Project of the Key Laboratory of Science and Technology on Waterjet Propulsion(No.614222303051117)the Joint Fund of CSSC(No.6141B03020301)。
文摘Water-jet propulsion is a widely applied ship propulsion technology.Its steering control system has an important impact on manoeuvre performance.In this paper,transfer function model is firstly established on the basis of mechanism analysis of water-jet steering system.Then,by considering the variability of model parameters and input constraints in practical operation,a model predictive controller is designed for steering system control.Subsequently,model based disturbance observer is employed in an attempt to reject environmental disturbances.The performance of the proposed model predictive control (MPC) scheme for a particular steering system is compared with that of conventional proportional integral derivative (PID) control strategy.Simulation results demonstrate that the proposed model predictive controller outperforms conventional PID controller,particularly in robustness,response delay and tracking accuracy.
基金This work was supported by the National Key Research and Development Program of China,No.2018YFB2000900。
文摘With the development and improvement of the hydraulic steering system,the articulated steering system became the research focus of numerous domestic and foreign scholars.The full hydraulic steering system with a compact structure and ease of operation,is widely used in articulated steering mode.Furthermore,its performance can directly impact the steering sensitivity and stability.This paper studies the working principle and actual structure of the priority valve and the steering control valve,which are very important.By setting up a mathematic model,the system’s load-sensing characteristics and the impact of steering control valve bypass throttle damping on steering stability can be analyzed.The Hydraulic Components Design(HCD)model was established for the hydraulic part of this system.It is proved that the model can reflect the system’s actual properties by comparing simulation and experimental results.The dynamic model is based on its actual prototype parameters by taking the tire and ground forces into account.The steering process’s dynamic characteristics are co-simulated in the 1D+3D system model by combining AMESim and Virtual.Lab Motion.The simulation results show that the system’s load-sensing characteristics ensure the sensitivity of the steering operation,and the bypass throttle damping has significantly improved the operation stability and lowered down the cylinder pressure fluctuations.This can improve the system performance by appropriate optimization.
基金Key R&D Plan of Shandong Province(2015GGX105005)。
文摘In view of the large energy loss problem in the traditional full hydraulic steering system,a scheme of replacing the ordinary pump with the priority valve with the load sensitive variable pump is proposed to make the variable pump provide the corresponding flow rate according to the needs of the steering system to achieve the purpose of energy saving.Through the establishment of the system AMESim simulation model,the data comparison shows that the energy loss of the load sensitive variable steering system is significantly reduced relative to the traditional full hydraulic steering system.
基金Project supported by the National Natural Science Foundation of China“Research on Critical Dynamic Buckling Conditions of Rotary Drill Strings and Post-buckling Snaking Swing and Helical Whirling Behaviors”(No.51904317)National Natural Science Foundation of China“Basic Research on Drilling and Completion in Complex Oil and Gas Well”(No.51821092)+2 种基金National Natural Science Foundation of China“Basic Research on Well Construction in Efficient Development of Shale and Tight Oil and Gas Fields”(No.U1762214)Special Topic on CNPC's Strategic Cooperation Science and Technology Project“Research on ROP Acceleration Technology in Deep Drilling in Terrestrial Shale Oil”(No.ZLZX2020-01-07-01)Science Foundation of China University of Petroleum(Beijing)(No.ZX20180414).
文摘Push-the-bit rotary steering system can greatly improve the rate of penetration(ROP),hole conditions and hole extension length and represents the development direction of modern steering drilling technology.In order to accurately predict and evaluate the build-up rate of pushthe-bit rotary steering system(RSS),this paper establishes the drilling trajectory prediction model and the calculation methods of‘limit build-up rate’and‘corrected build-up rate’for push-the-bit rotary steering system by comprehensively considering the interaction between thruster and sidewall and between bit and formation,the structure of RSS and other influential factors based on the mechanical model of the conventional RSS.Then,the influence mechanisms on the build-up rate are revealed from the aspects of‘leverage effect’,‘pendulum effect’and‘thrust effect’.Finally,the influence laws of thrust force,weight on bit(WOB),borehole inclination angle,bit and formation anisotropy on the build-up rate are analyzed.And the following research results are obtained.First,the build-up rate of RSS is the comprehensive result of various effects,among which‘thrust effect’plays a dominant role and‘leverage effect’and‘pendulum effect’play secondary roles.Second,as for the push-thebit rotary steering system,the proportion of‘leverage effect’increases,the proportion of‘thrust effect’decreases and the build-up rate declines with the increase of WOB.Third,the build-up rate is in a close relationship with structural parameters,thrust force,bit properties and drilling parameters of RSS.In conclusion,the research results can provide an important theoretical basis for the prediction of build-up rate of push-thebit rotary steering system and the optimization of RSS structure.
文摘With the economic globalization, the development of new technological revolution and the adjustment of industrial structure, the international trend of truck production are becoming more and more obvious. Mastering the basic knowledge of truck structure, understanding the basic principles of truck subsystem operation, being familiar with the functions of various components in the system and having the ability to solve truck failures independently are the basic qualities that every driver should have. The analysis of the principle and troubleshooting methods of truck steering system is helpful to improve the drivers ability to deal with emergency accidents, and also provides a powerful reference for the research and development innovation of steering system.
基金supported by National Natural Science Foundation of China (Grant No. 51005115, No. 51005248)Science Fund of State Key Laboratory of Automotive Safety and Energy of China (Grant No. KF11201)
文摘The tracking performance of motor current is an important factor that affects the assistance torque of electric power steering （EPS） system. Bad tracking performance will cause assistant torque delay, and make road feeling bad, and is influenced by the input steering torque and system measuring noise. However the existing methods have some shortages on system＇s robust dynamic performance and robust stability. The mixed H2/H∞ strategy for recirculating ball-type EPS system in a pure electric bus is proposed, and vehicle dynamic model of the system is established. Due to the existence of system model uncertainty, disturbance signals, sensor noises and the demand of system dynamic performance, the indexes of robust performance and road feeling for drivers are defined as the appraisal control objectives. The H∞ method is introduced to design the H∞ controller, and the H2 method is applied to optimize the H∞ controller, thus the mixed H2/H∞ controller is designed. The response of EPS system to the motor current command with amplitude of 20 A, the road disturbance with amplitude of 500 N and the sensor random noise with the amplitude of 1 A is simulated. The simulation results show that the recirculating ball-type EPS system with the mixed H2/H∞ controller can attenuate the random noises and disturbances and track the boost curve well, so the mixed H2/H∞ controller can improve the system＇s robust performance and dynamic performance. For the purpose of verifying the performance of the designed control strategy, the motor current tracking performance ground tests are conducted with step response input of the steering wheel, double-lane steering test and lemniscate steering test, respectively. The tests show that the mixed H2/H∞ controller for the recirculating ball-type EPS system of pure electric bus is feasible. The designed controller can solve the robust performance and robust stability of the system, thus improve the tracking performance of the EPS system and provide satisfied road feeling for the drivers.
基金Projects(51005115,51205191)supported by the National Natural Science Foundation of ChinaProject(QC201101)supported by the Visiting Scholar Foundation of the Automobile Engineering Key Laboratory of Jiangsu Province,China+1 种基金Project(SKLMT-KFKT-201105)supported by the Visiting Scholar Foundation of the State Key Laboratory of Mechanical Transmission in Chongqing University,ChinaProjects(NS2013015,NS2012086)supported by the Funds from the Postgraduate Creative Base in Nanjing University of Areonautics and Astronautics,and NUAA Research Funding,China
文摘The dynamic model of a novel electric power steering （EPS） system integrated with active front steering function （the novel EPS system） is built. The concepts and quantitative expressions of the steering road feel, steering sensibility, and steering operation stability are introduced. Based on quality engineering theory, the optimization algorithm is proposed by integrating the Monte Carlo descriptive sampling, elitist non-dominated sorting genetic algorithm （NSGA-II） and 6-sigma design method. With the steering road feel and the steering portability as optimization targets, the system parameters are optimized by the proposed optimization algorithm. The simulation results show that the system optimized based on quality engineering theory can improve the steering road feel, guarantee steering stability and steering portability and thus provide a theoretical basis for the design and optimization of the novel electric power steering system.
文摘Because the general object of ship steering control system is singular, the state Of rudder force and the state of disturbance are separated, and the generalized yaw output disturhance is obtained. Furthermore, singular system control problem of ship yaw and sway coupled system is transferred into nonsingular standard control problem. Then according to the linear fractional denoting algorithm of the rational function parameter perturbation system, the Linear Fractional Transform （LFT） model of yaw and sway coupled motion is solved, which is used to design the ship steering robust control system. For the ship steering system with the uncertain parameters, the robust control law is designed based on H^∞ μ-synthesis. And the robust performance of the system is analyzed and the simulation validation is made. Simulation results show that the designed control system has excellent control effect and robustness.
基金Project(51005115) supported by the National Natural Science Foundation of ChinaProject(KF11201) supported by the Science Fund of State Key Laboratory of Automotive Safety and Energy,ChinaProject(201105) supported by the Visiting Scholar Foundation of the State Key Laboratory of Mechanical Transmission in Chongqing University,China
文摘A novel active steering system with force and displacement coupled control(the novel AFS system) was introduced,which has functions of both the active steering and electric power steering.Based on the model of the novel AFS system and the vehicle three-degree of freedom system,the concept and quantitative formulas of the novel AFS system steering performance were proposed.The steering road feel and steering portability were set as the optimizing targets with the steering stability and steering portability as the constraint conditions.According to the features of constrained optimization of multi-variable function,a multi-variable genetic algorithm for the system parameter optimization was designed.The simulation results show that based on parametric optimization of the multi-objective genetic algorithm,the novel AFS system can improve the steering road feel,steering portability and steering stability,thus the optimization method can provide a theoretical basis for the design and optimization of the novel AFS system.
基金supported Foundation of National Development and Reform Commission of China (No. 2040)
文摘Pressure ripples in electric power steering （EPS） systems can be caused by the phase lag between the driver s steering torque and steer angle, the nonlinear frictions, and the disturbances from road and sensor noise especially during high-frequency maneuvers. This paper investigates the use of the robust fuzzy control method for actively reducing pressure ripples for EPS systems. Remarkable progress on steering maneuverability is achieved. The EPS dynamics is described with an eight-order nonlinear state-space model and approximated by a Takagi-Sugeno （T-S） fuzzy model with time-varying delays and external disturbances. A stabilization approach is then presented for nonlinear time-delay systems through fuzzy state feedback controller in parallel distributed compensation （PDC） structure. The closed-loop stability conditions of EPS system with the fuzzy controller are parameterized in terms of the linear matrix inequality （LMI） problem. Simulations and experiments using the proposed robust fuzzy controller and traditional PID controller have been carried out for EPS systems. Both the simulation and experiment results show that the proposed fuzzy controller can reduce the torque ripples and allow us to have a good steering feeling and stable driving.
文摘The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.
基金Project supported by the National Natural Science Foundation of China (Grant No.60674067)the Scientific and Techno-logical Foundation of Hubei Province (Grant No.2006AA101B13)
文摘In this paper, the performance of a column-type electric power steering （EPS） system and vehicle has been studied and a detailed mathematical model for the system has been established. Based on the mathematic model of the optimization design for steering feel, the parameters of the EPS system and vehicle on steering performance have been investigated. Moreover, the effects of the parameters on system stability have been analyzed and compared by the method of absolute sensitivity and the results are given in the end.
文摘A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of simpled steering resistance force and the relationship between assist gain and vehicle speed are presented for the first time. Assist character is found based on the parameters of a sedan at last. This assist character is fit for the control rule of the EPS system through analyzing this character. The assist character figure offers reference for system design and control. Furthermore, this research method has generality for assist character of different kinds of vehicles.
基金supported partly by the Aeronautical Science Foundation of China(No.20142852025)
文摘As all-electric aircraft has many advantages,an aircraft nose wheel steering system would be developed to the all-electric direction.Concerning the control demand of the nose wheel steering system,based on the basic principles of nose wheel steering system and the design technique of mechanotronics,an all-electric aircraft nose wheel steering system,composed of a nose wheel steering mechanism of two worm gear and a control servo system of fly-by-wire with both steering and anti-shimmy functions is designed to meet the demand for operation control in the nose wheel steering system.Then,based on the LMS-AMESim software,the simulation model of the system is established to simulate the dynamics for the verification of its steering function.The simulation results indicate that the nose wheel steering system is reasonable,and can meet the requirements of the general project.Furthermore,the prototypes of the steering mechanism and control system are studied to validate the design,and the steering test bench is prepared to test the designed system.The test results,such as steer angle,rotate speed of motor are analyzed in details and compared with the theoretical results.The analysis and comparison results show that the design is reasonable and the property of the prototype can achieve the design objectives.
基金Supported by the National Natural Science Foundation of China(51375007,51205191)the Visiting Scholar Foundation of the State Key Lab of Mechanical Transmission in Chongqing University+1 种基金the Funds from the Postgraduate Creative Base in Nanjing University of Aeronautics and Astronauticsthe Research Funding of Nanjing University of Aeronautics and Astronautics(NS2013015)
文摘A differential steering system is presented for electric vehicle with motorized wheels and a dynamic model of three-freedom car is built.Based on these models,the quantitative expressions of the road feel,sensitivity,and operation stability of the steering are derived.Then,according to the features of multi-constrained optimization of multi-objective function,a multi-island genetic algorithm(MIGA)is designed.Taking the road feel and the sensitivity of the steering as optimization objectives and the operation stability of the steering as a constraint,the system parameters are optimized.The simulation results show that the system optimized with MIGA can improve the steering road feel,and guarantee the operation stability and steering sensibility.
文摘With the gradual development of national economy, the mining task of coal mining industry has become more and more heavy. The demand for the mine wide body dump truck is also surging, promoting the rapid progress and development of the mine wide-body mine dump truck. However, the current hydraulic steering system still has high failure rate, vehicle steering system involves the safety of the driver, so people attach great importance to it. It is an important way to find and judge the possible failure points in advance and solve them pertinently. In this paper, the failure of hydraulic steering system is analyzed and the corresponding solutions are put forward.
