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In the field of construction, aerial work platform construction is indispensable construction equipment, construction of aerial work platforms use more scaffolding, derricks, gantry, construction elevators and a variety of lifting machinery and equipment, these devices large amount of material, installation cycle length, erection height restricted mobility is poor, so, research and development convenient, efficient and safe altitude platform instead of the conventional construction scaffolding has important significance. Aerial Work Platforms (referred aerial vehicles) are used to transport personnel and equipment to the prescribed height A movable construction machinery and equipment. This paper analyzes the structure of aerial work platforms mechanical systems, hydraulic systems and the use of functions based on the safe use of aerial work platform requirements, motion control and logic functions, proposed aerial platform based on PLC electrical control system solutions, the main research as follows: (a) first analyzed aerial work platforms mechanical structure, hydraulic control system and safety requirements, determine the aerial platform control and testing requirements. (2) studied the aerial work platform action, function, and safety requirements, on the basis of development and design of PLC-based electrical control system, using direct manipulation operation, PLC control and testing equipment status and generate action mode constraints to ensure reliable and safe aerial platform to run, to ensure the safety of operating personnel. (3) of the chassis leveling method, based on the principle of a plane defined by three points, select one of the three legs composing the plane, the first leg of the minimum height of the selected location as the control volume, adjust the height of this leg such that a direction inclination angle of 0 °; then select the next highest amount of control the height of the leg, the height adjustable legs so that the other direction of the tilt angle of 0 °, so that the chassis is adjusted to a horizontal surface; finally kept in two directions inclination angle of 0 °, the other two legs placed on the ground, to complete the chassis leveling. (4) In order to improve the reliability of the system, using a redundant design, the boom has a dual length / angle sensor to measure the length and angle of the telescopic boom studied redundant measurement signal arbitration algorithm to ensure that the length and angle measurement accuracy. (5) designed gondola automatic leveling control circuit, when the basket is more than 5 °, with manual leveling mode; when gondola less than 5 ° tilt, automatic leveling circuit drives leveling mechanism can tilt angle adjusted to the range of less than 1.5 °, the basket in a horizontal state.
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