Lateral Control in AHS Pushkar Hingwe Department of Mechanical Engineering University of California, Berkeley, CA [email protected] Masayoshi Tomizuka Department of Mechanical Engineering University of California, Berkeley, CA [email protected] Abstract This paper presents design and experimental evaluation of a vehicle lateral controller for Automated Highway S...

Spindle speed variation has been shown to be an effective method for chatter control. In this paper, a single-degree-of-freedom regenerative type chatter equation is treated using perturbation methods. Rather than using the time coordinate, the angle of revolution is taken as the independent coordinate for maintaining a constant delay in the equations. The spindle speed is taken to be harmonica...

High-speed milling operations of thin walls are often limited by the so-called regenerative effect that causes poor surface finish. The aim of this paper is to examine the link between chatter instability and surface roughness evolution for thin wall milling. Firstly, the linear stability lobes theory for the thin wall milling optimisation was used. Then, in order to consider the modal interact...

The objective in this work is to generate and discuss the stability results of fully-immersed end-milling process with parameters; tool mass m 0.0431kg, tool natural frequency 5700 rads , damping factor ξ 0 . 0 2 and workpiece cutting coefficient C 3.5 10 Nm ⁄ . Different no of teeth is considered for the end-milling. Both 1-DOF and 2-DOF chatter models of the system are generated on the basis ...

Two types of end milling at partial radial immersion are distinguished in this work, namely; up and down end-milling. They are theoretically given comparative study for a three tooth end miller operating at 0.5, 0.75 and 0.8 radial immersions. 0.5 and 0.8 radial immersion conditions are chosen so that analysis covers situations in which repeat and continuous tool engagements occur while 0.75 ra...

Machine tool chatter causes an instability that can occur in tool-workpiece-machine system. Hence surface roughness and tool wear in metal cutting processes. This instability caused by interaction between current tool positions and surface left by previous tool passes. Many methods have been developed to minimize the effects of regenerative chatter in machine tools and to enhance the damping ca...

Excessive deformations and chatter vibrations are two main obstacles frequently encountered in turning of long slender workpieces. So far, there is seldom reported research using optimization techniques to cope with those difficulties. This paper introduces a new method for optimizing the machining parameters and the sequence of cutting passes in turning of a slender rod to control the deformat...

ABSTRACT. S-transformation is proposed to evaluate the quality of completed turning operations. The calculated time-frequency-amplitude plot of an accelerometer or cutting force signal indicates the vibration level at different frequencies and helps the operator to identify the problems. Time-frequency-damping index plots were obtained by using the s-transformation. Variance of damping index in...