Katsuyuki Terada

Vehicle body vibration control apparatus

A vehicle vibration control apparatus in which springs (3A) and (3B) for supporting the vehicle body place in juxtaposition with cylinders (4A) and (4B) for damping the vertical vibrations and a cylinder (4C) for damping the lateral vibrations. The detection signal from the vibration acceleration detectors (5A), (5B) and (5C) are compensated for by compensator circuits (6A), (6B) and (6C), and further amplified by amplifiers (7A), (7B) and (7C) thereby to control the internal pressure of the cylinders (4A), (4B) and (4C) by servo valves (8A), (8B) and (8C). The compensator circuit is comprised in a such manner that the transfer function thereof takes the form of the product of an integration response element, first order lead response elements and first order lag response elements, and therefore the response characteristic of the vehicle body on the vibration acceleration has no peak over a wide range of frequencies.

Noise Characteristics of Current Collector for High-Speed Railway Using Delta-Shaped Collector Head.

High-speed railway noise comes from vibration and aerodynamic noises. Rolling noise from rail and wheel vibration and aerodynamic noise generated under the car body can be minimized with noise barriers constructed along the rails. Thus. noise radiated from current collectors becomes the dominant noise source, and it must be controlled to reduce noise emission from high-speed railways. A pantograph cover is a useful and effective apparatus that reduces aerodynamic noise from a conventional pantograph when the operating speed does not exceed 300 km/h. At speeds over 300 km/h. however, the cover does not reduce aerodynamic noise enough to meet Japanese noise regulations, and its lift also becomes quite large. A new concept for a low-noise current collector has been developed. This current collector uses a delta-wing shape for the collector and has a pair of insulators on a hydraulic mechanism covered by a streamlined dome. The noise level of the new collector is expected to be 19 dB lower than that of the present pantograph.

An Algorithm to lmprove the Steering Characteristics of an Automatic Guided Vehicle

Hunting reduction and travelling stabilization at high speed are required to improve the travelling characteristics of an unmanned delivery cart (AGV : Automatic Guided Vehicle), which is a component of modern FA system.In this paper, the travelling behavior model of an AGV is developped considering the inertia force and cornering force of the wheels. Factors which affect on steering characteristics are examined through simulation with the developped model and experiments. Steering control scheme is considered via examining limit velocity for stable travelling and control system stability. Finally, required factors for an AGV to travel on a straight line at high speed are high accuracy detectors, high response steering system, and optimal steering gain.In the experiment of the developped AGV with the forementioned control scheme, it was verified that the AGV can travel smoothly at 60 m/min with as little as ±16 mm amplitude and 3 sec. period hunting motion, which is less than the guiding tape width.