| || Design, Development, and Validation of a Vehicle-mounted Hydraulically-leveled Platform
Author : Senthilkumar, K.;Chidanand, M.;Nijalingappa, P.;Shivhare, Manish M.
Source : Defence Science Journal ; Vol:60(2) ; 2010 ; pp 169-177
Subject : 621 Mechanical Engineering;Defence Science Journal
Keywords : Hydraulically-leveled platform;ISO shelter;ISO corner;deflection;stress;strain gauge;accelerometer;data acquisition system
Abstract : Hydraulically-leveled platforms are required, to provide a leveled base for accurate leveling of high-rise masts and other vehicle-mounted communication devices. Design, development, and validation of one such platform on an 8x8, high mobility, wheeled vehicle is presented. The platform is a welded structure, designed to accommodate two ISO type shelters, and the shelters are secured to the platform at their four ISO corners using special twist locks. The leveling of the platform is enabled by actuation of four hydraulic cylinders bolted to the vehicle chassis. The concentrated type loading, resulting due to clearance maintained between the skids of shelters and the platform, and the loading pattern are the major design considerations. The other factors that have bearing on the design of platform include accommodation of variants of shelters, ease of operation of equipment mounted on the original chassis, and load distribution on axles, over-all height, ground clearance and departure angle of the integrated entity. Deflection and stress analysis of the platform structure using finite element analysis has been carried out for two types of shelter loadings. Limited track trials have been conducted at Vehicles Research & Development Establishment (VRDE) for assessment of structural integrity of the platform, and constructional and mobility aspects of platform-mounted-vehicle. Measurements of strain at critical locations, under-shelter loading, and while driving the vehicle at two different vehicle speeds on pave and cross-country tracks, have also been carried out for validation of design of platform. Details on problems faced during track trials, and the subsequent modifications carried out to the platform are also discussed.