| The ability of braking means that in the course of trip, it can reduce its speed by force so that the bicycle can stop according to needs. It is one of major performance of motor-cycle, and it directly concerns the safety of motorcycle. Motorcycle anti-block braking system has the characters about self-governed brake. If it can not carry out in the course of braking, you will meet the traffic accident. Motorcycle Anti-Lock Brake system (ABS) is based on the system of high technology of development that the adhering character of tyre and road surface changes with slip rate. It comes from the principle that prevents the wheel from blocking in the braking course, avoiding that the rear wheel of motorcycle swings and front wheel loses the ability of changing direction. Then, it can reach the purpose that raises motorcycle brake stability, maneuverability and safety. Motorcycle ABS is a kind of initiatively safe technology that has greatly raised the brake safety performance of motorcycle. Using the software of Matlab, the article starts with the ABS braking system of motorcycle simulation , which has established the mathematics model of braking system ,and has analysis brake curve and discussed the feasibility of use that install ABS in motorcycle .It is good and basic to design and use motorcycle ABS system. The full text is divided into 5 totally chapters. The content is as follows: 1﹑Introduction I have introduced the importance of braking system in motorcycle design, as well as the developing present situation of domestic and international ABS anti-block braking system. After discussing the method of control of ABS, have analyzed to slide mould form change structural control, optimum control law and the control of slip rate with add and slow down the control methods, By contrasting, this paper choose Bosch control theory. At last, elaborating the major research work of this paper. 2﹑Basic structure and the working principle of motorcycle ABS The function of ABS is to make the wheel be slippery side state through regulating and controlling brake pipeline pressure and avoiding wheel in brake course by holding and slip. The control of vehicle is to control active force between the wheel and road surface. And the active force between vehicle and road surface is decide by the adhere coefficient of tyre and road surface. Retarded motion and the acceleration of vehicle receive wheel mainly longitudinal adhere the restriction of force vehicle change direction the ability of sport and resistance outside lateral force role receive wheel mainly lateral adhere the restriction of force. To fully develop the latent adhere ability between tyre and ground, motorcycle braking system begins to install anti-lock device. When braking urgently, anti-lock device can prevent wheel from holding completely and coming into the half hold half roll to move state where the wheel have biggest longitudinal adhere force and great side direction adhere force. Using its peak value force to raise braking speed and shorten brake distance. Anti-block brake system is mainly made up of wheel sensor, pressure regulator and control equipment. Wheel sensor is formed by biography sense and tooth circle etc. Pressure regulator is formed by scavenge oil pump, memory and electromagnetism valve. Electronic control equipment (ECU) is the control core of entire ABS. In this chapter, the basically working principle, role and composition of ABS have been introduced briefly , and have introduced the three kinds of composition part of ABS respectively ——principle and the role of sensor, controller and pressure regulator. I have introduced some kinds of composition forms of motorcycle ABS finally. 3﹑The control technology of motorcycle ABS This chapter has first introduced the major factor that affects control technology, and analyzed the influence between the slip rate with adhere and controlling technology on the different surface. According to it, I discuss the various control methods of domestic and international adopting, in which include: 1. The ABS with slip rate as control goal is to control form with continuous quantity and keep best and steady slip rate in brake course. But the requirement of rotational speed and wheel is higher. It need higher measure equipment cost; 2. The method of controlling with logic door limit value need not establish the mathematics model of specific system, and is very efficient for systematic nonlinear control, and suits the control used in ABS fairly. On the other hand, it needs the higher requirement of parameter sets. It is instability to control; 3. Based on the optimization control method of state space law, we can use the concept of state space law according to vehicle -ground systematic mathematics model, study in time-domain that defend holds thevarious control requirements of dead system, presses principle of optimality. We can get the control index calculation. But the systematic good bad precision for vehicle -ground systematic mathematics model has higher requirement; 4﹑The slippery mould that occurs change by using feedback control structure changes structural control method, this kind of method is very high for speed requirement. After contrasting, we have adopted logic door control method of limit value. In the method of the restriction control of the house opposite, the problem that door limit value brings to solve with acceleration and slip rate will occur. This paper has adopted corresponding Bosch control method. Bosch has used this parameter of slip rate fully. Making up wheel deceleration degree signal, acceleration and the signal of slip rate are used to make control parameter. When being lower or being higher than door limit value, control organization which adopt the method of reducing pressure, insuring to press and pressure boost, adjust the acceleration of wheel. This paper finally introduces the crucial technology that realizes the Bosch logic control, such as: calculation and the detection of ship speed, calculation of +a and -a, calculation of referring speed and slip rate ? , the identification of road surface adhere state, brake pressure with ladder shape pulse control technology. 4﹑Analysis and the establishment of simulation model of motorcycle brake state In this chapter, using a wheel and the truckload analysis that gets power and moment, simulation models has been established. The simulation model mainly includes some following son models: Truckload model, tyre model, brake model as well as ABS controller model. In every son modular, we have get F, wheel acceleration, slip rate and adhering parameters respectively. We have made necessary preparation for simulation software compile in the next chat. 5,the introduction of simulation software and the simulation of braking course In this chapter, based on the partition of every son modular in simulation model, we take Win2000 as development platform, Matlab as a kind of simulating tool, and have drawn up the computer simulator in motorcycle ABS brake course. Using this software for the brake course of motorcycle ABS, we make the computer simulation, and analysis performance. Through changing the initial data that has been input, we simulated and analyzed under the different conditions suchas : the same and different surface, initial speed and difference turn inertia , fully loaded and idle , the different brake moment change rate. Then, we have painted changing curve with every parameter concerning brake course at any time, including speed changing curve, brake moment changing curve, adhere coefficient changing curve, the changing curve of slip rate and brake distance changing curve and wheel acceleration changing curve. Soon afterwards as not adhering together, the brake moment change on coefficient road surface that changes and turns inertia, for brake time and brake, is away from the influence that produces, have carried out corresponding analysis, have listed corresponding form. So I have reached use ABS installation for wheel defend hold dead time postpone to play the part of the conclusion of effective role. 6﹑Conclusion In this chapter, I have drawn the conclusions as follows: 1. Adopting ABS can shorten vehicle distance and the brake time, raise the brake performance of motorcycle apparently, especially braking stability; 2. Motorcycle brake initial speed has influence for logic door limit, is different and first to use different door limit value quickly, first speed is the more high, the absolute value of door limit value is the more big; 3. The result of motorcycle and the performance of dynamics parameter have certain influence ABS. When parameter is changed, logic door limit value should also change. It means that different vehicle type, even if a kind of same ABS using, also needs do adjustment for logic parameter, because of its parts the difference of parameter; 4. Even if the same motorcycle and the different road surface, its logic parameter is also different, so, the best control way is to adopt from the way of adaptive control in brake course, before taking notes a logic parameter, contrasting with current road surface, and revise parameter at any time in order to get the pressure control signal that most meets road surface.
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