Steering system

All control systems whether they be process plants, steering systems, living organisms, or industrial corporations may be regarded as information processing systems. They obtain information, analyze it, and on the basis of their analysis generate new information to take some kind of action. 

Force sensors are not used in general automotive applications. In agricultural machines a force sensor measures the load at the connection rod [1], Some force sensors are specially made for measuring forces during vehicle testing and validation. Often metal strain gauges are welded to the devices under test The data is sometimes needed for system development or to verify simulation results. The first and only mass production of torque sensors is in electrical steering systems [2]. 

A force sensor combines a structure that responds to force changes with a sensor that converts these changes into a signal. A torque sensor similarly consists of a torsion or tension element detector, but it also has to transmit the force. Consider the torque for a electric power steering system any failure would immediately mean loss of control of the vehicle, so this must be avoided under all circumstances. Steering column torque requires careful finite element calculation, durability and performance testing to failure, and validation. 

Electric power-assisted steering systems are more and more replacing hydraulic systems. To improve fuel economy, the power assistance is provided by an electric drive. Such a system only consumes energy when power is supplied, unlike hydraulic systems. A torque sensor in the steering column provides the input signal to the drive control unit. An example of an electric power steering system is shown in Fig. 7.12.4. 

One of the latest developments in the area of steering torque sensors is an optical concept created by Bishop Innovation with Bosch. As in conventional hydraulic steering systems, a torsion bar is a part of the steering column. A disc with a barcode on its surface is attached to each end of the torsion bar. A light source within the sensor module illuminates the surface of the coded discs, partially reflecting the light through a lens onto an optoelectronic ASIC. 

The light intensity on the sensitive surface of the optical ASIC, an array of photodiodes, depends on the code of the discs. The intensity distribution over the photodiodes allows the optoelectronic ASIC to calculate the absolute angular position and the angular displacement of the steering shaft Fig. 7.12.6 shows the sensor concept. This concept allows measurement of the absolute angular position of the steering wheel and the torque applied to the steering system. 

A multipurpose torque sensor was developed by FAST Technology. The specifications of this sensor allows its use in electrically assisted steering systems. FAST Technology developed a method for permanently magnetizing ferromagnetic steel shafts. Fig. 7.12.11 shows the shape of the toroidal magnetic field. The magnetic field beside the shaft varies with the mechanical stress on the shaft. A sensor... 

A vehicle is a device used to transport objects and equipped with a powered locomotion system and a steering system. A vehicle can be guided by an operator (driver) or by an electronic controller. In this last case the vehicle is usually named automated guided vehicle (AGV). 

Walkie trucks can be considered the battery-powered version of the hand-operated forklift trucks. They are equipped with wheeled forks used to lift loads. The worker usually does not ride on the vehicle, but he controls the speed and the steering systems by using a control handle in front of the vehicle. For safety reasons, the maximum speed is limited to about 5 km/h, therefore no more than the normal speed of a human worker. 

The optical system is based on a painted strip used to define the path. An optical sensor is placed on the vehicle able to detect the reflected light by the strip. The signal generated by the sensor is used to control the steering system. 

Uses of nylon bearings include bushes in domestic appliances bushes, thread guides, rollers and slides in textile machinery ball joints and bearings in suspension and steering systems in cars. 

The steering system is loose or worn Tighten or replaee the steering linkage... 

When replacing the parts, please carry out replacement carefully and correctly, any minor error may influence the performance of the steering system and result in the accidents and danger at the time of driying. 

In the course of the steering or replacement of hydraulic oil, the time of the steering wheel being turned to the extreme positions shall not exceed 5 seconds so as to avoid the damage to the steering system. 

Power steering system consists of steering oil pump, oil reservoir, power steering gear and the oil pipe. 

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