The Research Of Self-propelled Howitzer's Braking System

With the demand for the modern war, all military powers in the world are actively developing lighter, digital artillery. And to improve the mobility of howitzer, the military at home and abroad are towed artillery on the allocation of auxiliary propulsion system (Auxiliary Power Unit, APU). Artillery braking system is an important component of the APU. This paper presents a new double-loop outside brake valve and double-loop hydraulic accumulator valve constitute artillery dual hydraulic circuit system dynamic system for the artillery to take braking.This paper improves the braking system on the base of a certain type of homemade howitzers APU installation. As the artillery's original brake system has a lot of shortages, such as a long response time, easy to leak out and the poor ability to adapt to the terrible environment, its performance is greatly curtailed in the use of the process. Considering the performance and structure of the components, we use the United States MICO double-loop outside brake valve as a control device of the brake system in this paper. The valve plate edge with a foot pedal brake pressure proportional to a rapid response, a foot plate natural feelings, and its quality is reliable. Braking System uses two oil-storage devices made in MICO companies and uses the double loop hydraulic accumulator valve hydraulic accumulator. The working principle of the braking system: The self-propelled Gun carriages share a hydraulic pump with the braking system control circuit. When the military is self-propelled, hydraulic oil goes into the accumulator hydraulic circuits. On the condition of accumulator kept constant pressure, hydraulic oil goes through the double-loop hydraulic accumulator valve with the minimum pressure drop. If it is necessary, the driver rides double circuit brake under the foot plate to promote the heart of the valve to turn off it. Meanwhile, higher pressure fuel oil is out from the valve, going through the brake shuttle valve into the tank, so brake is taken. In unforeseen circumstances, Gun carriages power is out of use,it can be relied on to complete two brake accumulator to ensure the safety Gun carriages. Wheel independent double-circuit brake system can guarantee that the failure of a circuit racer circumstances get the necessary braking force, so that the braking system is reliable. Besides, the parking brake can be also realized by this system.In the system of howitzer's braking system, the double-loop hydraulic accumulator valve is one of the most important components, whose characteristics will give a brake great influence on the system, and its characteristics is the key to the success of the system. Therefore, in this paper, the mathematical model of the self-propelled braking system is build up, which will be the base of the analysis about the characteristics of system parameters to improve system performance and lay the groundwork. To simplify the system model, the two external brake circuit can be simplified into two parallel three links valve, the flow equation isThe pressure equation is:Combination of brake cylinders by the equilibrium analysis, we can find out the mathematical model:Obviously the system is an open-loop one. After the physical model of Artillery braking system is completed, to verify that the system performance parameters satisfy the design requirements, we simulate artillery braking system with computer based on the platform of AMEsim., launched AMEsim is a new High modeling and imitation Software made by the IMAGINE France since 1995. It is seniorengineering modeling and simulation platform, whose full English name is the Advanced Modeling Environment for Simulation of systems. It is based on the intuitive graphical interface modeling platform, in the whole process simulation system simulation is showed up in the platform. Compared with other simulation platform such as Matlab/simulik, AMEsim can build more intuitive system model, as well as considering various parameters of complex systems. Due to the double-loop hydraulic accumulator valve used in this paper is not a standard external brake components, this paper's core is building the new braking system simulation model based on the platform of AMEsim. The model of the valve is shown in the following figure.It can be concluded through the analysis on simulation results: the brake system's response time is very short, and the braking process is smooth. When the power system is not providing the source, more than 5 brakes can be taken. All performance indicators satisfy design requirementsLimited by the laboratory conditions, this paper only gives the bench test on the artillery - circuit brake system.Finally, in order to meet the needs of modern warfare, the paper gives an idea that energy-saving brake can be realized by the second-conditioning system on the base of artillery braking system.