Control of the stroke of hydraulic cylinders in hydraulic lifting mechanisms of installation equipment
For the correct operation of hydraulic lifting mechanisms of the installation equipment of rocket and space complexes, it is necessary to ensure the synchronous movement of the rods of hydraulic power cylinders operating in parallel when performing working operations. Therefore, the urgent task is to develop synchronization systems that, along with ensuring the consistency of travel speeds, also provide the consistency of the mutual position of hydraulic cylinder rods. To solve this problem, we introduce a new approach which makes use of indirect methods for determining the working stroke of hydraulic power cylinders according to the results of measuring the angular or linear coordinates of the power elements of the mechanism. The first method is based on measuring the angular coordinates of the power elements of the lifting mechanism using angular displacement sensors - angular encoders. As for the second method, it relies on measuring the stroke of an additional link of variable length by means of magnetostrictive and cable linear position sensors. The paper briefly describes the device and the principle of operation of the sensors, and gives recommendations for the construction of measuring transducers as part of the lifting mechanism of the installation equipment. The new approach to solving the problem of controlling the stroke of hydraulic power cylinders in lifting mechanisms can be used in the development of advanced installation equipment for launch vehicles of heavy and superheavy classes.
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