Dump Truck based on virtual prototyping technology optimization of lifting mechanism

Along with the virtual prototyping technology, represented by the continuous development of computer technology, virtual design engineering fields gradually become a new means of modern design. Currently, the virtual prototyping technology has been applied to the automotive product research and development, and initially formed a set of professional theory, engineering design, scientific experiments, such as one of the more complete application system. The use of virtual prototyping technology, the early stages of product design analysis and evaluation of product performance, optimize the design parameters of the physical prototype, thus reducing the risk of new product development and shorten the development cycle, improve product performance, and ultimately improve their market competitiveness. In this paper, STQ3163L9Y6 dump truck as the research object, virtual prototyping software ADAMS and ANSYS for the application platform, systematically dump truck lifting mechanism and the key structure to optimize the design. This paper introduces the research background of virtual prototyping technology and its current development at home and abroad, an overview of multi-body dynamics and finite element method theory and its application software ADAMS and ANSYS; Then, according to mechanical optimal design theory, applicationADAMS, dump truck lifting mechanism established virtual prototype model and its dynamic simulation analysis and the results showed that: the key to the lifting mechanism to optimize the design of the hinge point to optimize the results achieved to decrease the thrust of hydraulic cylinders to improve lift The purpose of the performance of hoisting mechanism; and then apply the arm triangle ANSYS software for finite element analysis and the results showed that: the original materials, the irrational use of triangular arm, with variable density method for topological optimization arm triangle design, optimization results show that: in ensuring the rigidity and strength of the premise, the quality of the triangular arm before optimization 67.759kg reduced to optimized 45.702kg, reduced 32.6%, to achieve a lightweight design arm triangle; Finally, a dump truck in the vehicle model, self-excited vibration of the hydraulic cylinder in case of change of thrust, the results show that: consider the self-excited vibration of the vehicle, the tank will produce a certain thrust fluctuations, while generating self-excited vibration of the vehicle factor - suspension parameters optimal design, the cylinder will decrease the maximum thrust, and fuel tank thrust decay rate fluctuations there is considerable improvement, these suspension systems for truck design effective reference. This study successfully applied to the virtual prototype of the Tipper lifting mechanism optimization design, virtual prototyping technology in the same time, the field of application of special-purpose vehicles also have some reference value.

 

Keywords: dump truck lifting mechanism, optimum design, triangular arm, topological optimization, vehicle model

Used in bridge health monitoring system of the Distributed Control System

Bridge Health Monitoring and Data Acquisition system is currently in the construction and operation of the bridge is a relatively new research direction, which covers the structural design of the bridge and controlled the two major areas of data collection, according to the characteristics of a bridge monitoring system, usually distributed acquisition approach. Instance of this research at home and abroad, for the domestic large-scale bridge health monitoring system booming in recent years, and strive to systematically distributed data acquisition applications in bridge health monitoring to do a more comprehensive study. This paper analyzes the bridge health monitoring system for the background, development, current problems, etc., CAN bus is proposed to constitute a distributed monitoring network is designed to monitor the development of the discourse on the bridge. Bridge monitoring system for data collection, data processing and data transmission module works, hardware design, software design and implementation of their method for a more in-depth discussion and detail.Meanwhile, the host computer's local server and remote client design are introduced in detail. Finally, the overall implementation and design issues that need attention and improvements can be made later. 

Keywords: bridge monitoring; CAN bus; bus communication; local server; remote client

 

LabVIEW Based Hybrid Electric Vehicle Drive System

Environmental protection and energy conservation has become urgent to solve the two main themes of social, internal combustion engine and motor as a power source as energy saving hybrid vehicles of choice, which set starter / generator in one of the ISG (Integrated Starter Generator) hybrid cars become of great practical significance and direction of the car. Hybrid vehicle product development, the most critical aspect is based on different hybrid drive systems to develop and optimize the control strategy.How hybrid car engines, electric motors, batteries and a good match between the three optimal control is the development of hybrid cars to solve the problem and not yet fully resolved technical problems. Built directly on the physical prototype development of hybrid drive systems need to spend a lot of energy. Therefore, the theory of hybrid drive systems modeling, virtual simulation and analysis is a very important product pre-development work. In this paper, mild ISG parallel hybrid electric vehicle as the research object, respectively, and virtual instruments based on bench test equipment to the platform of LabVIEW virtual instrument software to build the system model to study its drive system, specifically as follows: (1) introduced hybrid of domestic and international actuality of the ISG hybrid vehicle as the object of study the causes and significance. (2) analysis of the structural characteristics of hybrid vehicles, control strategy and its key technology. This paper introduces the common hybrid vehicle simulation software and virtual instruments and simulation software LabVIEW, and analyzed the software of choice hybrid vehicle drive system advantages. (3) of the hybrid electric vehicle structure and control strategy analysis, ISG hybrid vehicle drive system of the main components of the engine, motor and battery for the selection, and the power from the car, economy, and considering the cost of the main components of the design parameters. (4) Finally, the laboratory bench and were based on virtual instrument data acquisition system DAQ (Data Acquisition System)-based access to relevant data and signals, and then write a program on the LabVIEW software platform to build the engine, ISG motor and batterymodel, and the results were analyzed to verify the model and parameter design is reasonable. Through the rational selection and parameter design, can achieve hybrid car engine, motor, battery good match between the three and optimization of control and improve the HEV power system and economy to meet the practical significance of the development of low emission, low fuel vehicle requirements. 

Key words: ISG, LabVIEW, data acquisition system, drive system, matching and optimal control

 

Based on Virtual Prototyping of Active Front Steering Control

Steering system directly affects the performance of vehicle handling and stability, is to ensure the safety car at high speed is an important performance. Steering system can not meet the traditional low speed flexibility and high speed stability requirements.Active front steering vehicle traveling state can achieve the desired steering ratio, while simultaneously the flexibility to meet the low-speed stability and high speed requirements. Retention of active front steering system with mechanical connections, the driver can feel the real "road feel." Therefore, the flexibility of driving, comfort, stability and security considerations, active front steering system steering is today an important direction of research and development. In this paper, ADMAS / Car platform, built for active front steering of the vehicle model. By turning the sine sweep test simulation to verify the correctness of the model built vehicle. In the low friction coefficient and high friction coefficient road test under the separate hunting simulation results show that: in the extreme conditions, vehicle yaw rate and sideslip angle response to steering wheel angle can change with the car is easy to lose stability. In this paper, a robust nonlinear fuzzy PID control model of vehicle stability control, cornering performance to a satisfactory model of two degrees of freedom as a reference model. The fuzzy PID controller yaw rate and sideslip angle as control targets to vehicle yaw rate model and the ideal difference between the yaw rate as the control variable. Tolerance approach by the stability of the car to judge, the use of ADAMS / Car and MATLAB / Simulink software co-simulation of two. Simulation results show that: Active Front Steering Vehicle Stability Control to expand the area to prevent vehicles advance into the nonlinear region and saturation regions, especially in excessive steering condition, the control effect relatively clear. As conditions in the limit tire slip forces are easily filled, active front steering to improve vehicle stability control system of limited, so this paper, active front steering and variable torque distribution of the need for joint control. Design of active front steering and variable torque distribution joint control of the fuzzy controller.Controller to vehicle yaw rate model and the ideal difference between the yaw rate and vehicle sideslip angle model as input variables, the previous round of the overlay and the additional yaw moment angle as output variables. Using phase plane method of tolerance zones and to determine whether the car unstable. In the face of low adhesion road control system for a double lane for simulation, simulation results show that: joint control can keep the car's stability, its effect is superior to separate active front steering control, sideslip angle and horizontal control the swing angular velocity response are ideal range. 

 

Keywords: active front steering; fuzzy PID control; variable torque distribution; co-simulation

Active Suspension Based on Genetic Algorithm Multiobjective H <, 2> / H <, ∞> robust control

Active suspension as a future major trends in automobile suspension systems, more and more attention and research. However, to fully active suspension damping performance, the need for suitable control strategies and design a suitable controller, it can be said of active suspension control technology is the key. The key paper for active suspension control technology to carry out the research. For solving the problem of active suspension control, the most difficult is the ride comfort and handling stability of the multi-objective optimization. As the vehicle suspension system design evaluation of the most important indicator of the conflict between them is contradictory. Reduce the stiffness of the spring suspension system will get a better comfort, but this time the suspension of the dynamic travel will increase, the magnitude of the larger body is not conducive to the operation of the vehicle stability. The increased spring stiffness, ride comfort will decrease. Active Suspension for solving multi-objective optimization problems, different theories have been based on a large number of methods that most of the body vertical acceleration, suspension travel, with the static load as the optimal ratio of performance objectives, the selected weights, then unified into a target function to optimize. However, this body acceleration may be less than ideal results. For the above problem, the paper first establish two degree of freedom quarter car active suspension system model, then the constraint H ∞ controller design, and application of MATLAB to solve the LMI toolbox, and the results for solving the simulation compared with the passive suspension. Next, the paper combines the H ∞ control and the merits of H2 control design of the H2 / H ∞ mixed-active suspension controller, making the body acceleration in the time domain have a good effect, and the system has some robust stability . Solved by LMI, and simulation results with constrained H ∞ controller were compared. Finally, the paper Genetic algorithm based on H2 / H ∞ controller for solving the hybrid simulation results show that solving the LMI approach although efficient and effective, but for the H2 / H ∞ multi-objective hybrid controller problem solving, there must be conservative , and genetic algorithms for dealing with difficult to solve the nonlinear multi-objective problems, there is a strong optimization. Therefore, based on genetic algorithm H2 / H ∞ controller for active suspension mixture can be effectively controlled, not only greatly improved the ride comfort, to ensure the stability of operation, and has strong robustness. 

Key words: active suspension, LMI, H ∞ control, H2 / H ∞ mixed control, genetic algorithms

 

Fuel cell electric vehicle power system parameter matching and optimization

Development of fuel cell electric vehicle is to solve the current energy shortage and environmental pollution is one effective technical approach. To improve the efficiency of power system as the goal, of multi-energy method of power system optimization, building from the fuel cell components and auxiliary electrical power source - electric hybrid power systems, fuel cell vehicle development has become a key technology. In this paper, fuel cell electric vehicle system design for the study, to fuel cell electric vehicles, hybrid electric power system parameter optimization focus of a lightweight fuel cell bus power system matching and optimization of the parameters, the main course of the study and the results are as follows: (1) First, review the fuel cell electric vehicle power system parameter matching and optimization studies, which mainly summarizes the parameter matching and optimization of hybrid methods that enhance fuel cell hybrid electric vehicle electric power system matching and optimization research is to improve the power efficiency of the system an effective way. (2) comparative analysis of the fuel cell electric vehicle power system configuration, obtained indirectly, the structure of fuel cell hybrid system is more suitable for fuel cell electric vehicles. Optimization of the hybrid system configuration under the basic principle, the two indirect fuel cell hybrid system architecture (FC B, FC BC) were analyzed. Based on the typical characteristics of vehicles and fuel cell power source for hybrid system analysis of technical points, with a bus the technical parameters of the original model to determine the fuel cell system and lithium iron phosphate group of the hybrid power system programs. (3) fuel cell hybrid power system for the parameter design problem, the proposed hybrid system of electric power mixed with the concept, and vehicle dynamics theory, the design of hybrid power system parameters into the design of mixed degrees problem, get a fuel cell hybrid systems with mixed degree of design methods, based on the degree of the fuel cell hybrid electric vehicle power system design parameters, determine the total power of the power source, mixed boundary value and the degree of motor parameters. (4) According to the fuel cell hybrid power system optimization problems, established a dynamic vehicle for the constraints to optimize the fuel economy target for the non-linear mathematical model to determine the optimal objective, optimization variables and optimization constraints. At the same time for the inadequacies of the basic genetic algorithm, an improved hybrid genetic algorithm to solve optimization problems. The optimization results are significantly improved compared with that before optimization, verification of the hybrid genetic algorithm. The article also analyzes the mixing degree, SOC value of optimization goals. In summary, the text on the fuel cell electric vehicle power system configuration optimization, parameter matching and optimization of power system studies, for further experiments with the prototype vehicle powertrain design provides a theoretical basis for the development of fuel cell electric vehicles with some reference value; particular degree of power based on hybrid electric hybrid power system parameter design method and hybrid genetic algorithm to optimize the hybrid system in the application of hybrid power systems for other parameter matching and optimization also has some reference value. 

 

Keywords: Fuel cell hybrid electric vehicle electric power system parameter matching and optimization of mixed-based hybrid genetic algorithm

Vehicle deviation line automatic detection system, image processing technology

The automotive vehicle driving wandering the course of a relatively common failure. The failure will result in driving the process, the driver always need to apply a corrective force on the steering wheel, which will increase the difficulty of the operation of the driver, the driver likely to cause fatigue, heavy steering, speed up the parts and tire wear, resulting in system dynamic sliding phenomenon. Especially when the emergency brake on the highway, may also cause serious skid, which caused a major traffic accident, the harm is enormous. The national standard GB7258-2004 "Safety requirements for operation of motor vehicles" is a mandatory standard, the 4.13 states: linear motor drive, its front and rear drive shaft connection with the center line of track should be the same. Now, however, can not exist a set of scientific and accurate detection of the vehicle for the system deviation. Vehicles are usually carried out only at the factory wheel alignment test, people are also found in the actual use of the vehicle after the repair there is deviation problems. There is deviation in order to avoid the problem of automotive products into the market, all vehicles before leaving the factory testing is very necessary.This paper presents a wandering line of vehicles to achieve automatic detection system.The detection system connected with the production line, the vehicle test track trigger photoelectric switches, driver CCD (Charge Couple Device) cameras capture images of vehicles. Image processing module is the vehicle deviation line automatic inspection system, the core content of the main content of this thesis is that the system is based on LabVIEW to image processing and image capture technology. The first chapter of the machine vision, digital image processing concept, development status at home and abroad made a brief introduction. The second chapter analyzes the choice of image processing hardware. Including optical lens, CCD camera, photoelectric switches, light sources and lighting systems, etc., for the practical use of different applications. Through repeated testing, the accuracy of the system meets the requirements of factory production, efficient, adaptable, high degree of automation. The third chapter in theory, through comparative study, the final choice a reasonable recognition method of image processing: median filter, LOG sharpening operator (Laplacian of Gaussian). After image enhancement, image smoothing, edge sharpening, after making the collected images highlight the target area, the edge of clear and complete, by template matching and accurate positioning of the vehicle, the vehicle was finally calculated the deviation information. Chapter IV focuses on the on LabVIEW platform, modular thinking in the application of IMAQ function, to achieve the above functions, to achieve real-time detection. Extraction of the vehicle is different from the usual method of contour to locate the vehicle, the optical sign is proposed as an alternative test method aids, this method greatly reduces the complexity of procedures, convenient and intuitive, and high precision to meet the complex the test environment. Chapter V of the system accuracy do experiments. Finally, the results of this study design and inadequate to do a simple summary. 

Keywords: vehicle deviation test, LabVIEW, image processing, machine vision