基于扩展Kalman滤波器测量氮爆式液压锤的性能

考虑到在缸体内运动的活塞，难以用传感器直接测量其运动状态：速度、加速度以及摩擦力、未知阻力。根据系统理论的方法，以活塞的位置、速度、加速度作为状态矢量，在采样间隔内，将活塞运动视为匀加速度运动，建立具有未知输入的活塞运动状态方程。将未知阻力视为有色噪声，并作为系统未知输入，设计扩展状态的Kalman滤波结构。依据气体的变化规律，得到活塞在采样各时刻的位置坐标。以最小方均误差作为测量准则，研究有色噪声输入线性系统的Kalman递推状态估计算法。算法自适应跟踪未知输入的变化，估算活塞冲程、回程的速度和未知的阻力，从而测量氮爆式液压冲击锤的冲击能量。测量结果表明，该方法具有较高的测量精度，与理论设计基本一致。

PERFORMANCE OF NITROGEN EXPLOSION HYDRAULIC PERCUSSION HAMMER BASED ON MEASRUEMENT OF EXPANDED KALMAN FILTER

In consideration of moving piston in the cylinder, it is hard to measure by sensor to describe its moving state variables: speed, accelerative speed, friction force and unknown resistance directly. Based on the systematical theory method, the position, speed and accelerative speed of the piston are regarded as state vectors. The piston moving can be regarded as evenly the accelerative motion in sample interval. The state equations are built to describe moving of the piston with unknown input. An expanded structure of Kalman filter is designed with unknown input when the unmeasured resistance is regarded as colors noise. On the basis of gaseous variety regulation, the position coordinate of piston is obtained by computer at each sampling interval. The minimum square error(MSE) is employed as the measure rule. The estimate recursive algorithm is researched to calculated state variable with color noise as the system input. The algorithm adaptively scents the changes of the unknown input. With the estimate of computed speed and unknown resistances of the piston in the stroke, the percussion energy of the nitrogen explosion hydraulic hammer is measured by expand Kalman filter. The result shows that the method has better precision of the survey and agrees with the theoretical design on the whole.