Research On Structure Of Building Maintenance Unit’s Chassis And Development Of Parametric Design System

The Building Maintenance Unit(BMU)is a high-altitude operation equipment installed on the top of high-rise building for cleaning and maintenance of building’s exterior wall.It is mainly composed of telescopic arm,column and bottom frame.It is mainly composed of telescopic arm,upright and chassis.With the design of high-rise buildings more novel and unique,the building maintenance unit industry is also developing rapidly,In this process,the structure system of telescopic arms and columns has been improved,but the underframe structure is slightly inadequate in adapting to the new working environment.This paper aims at the roof rail BMU with the highest market share as the research object,designs new underframes of BMU suitable for different working environments and develops a corresponding computer-aided design system.The specific work is as follows:First of all,according to the design principles and requirements of the underframe,in view of the working environment of laying a horizontal track with a small turning radius,the design scheme of three types of x-type chassis was proposed according to different bearing requirements,and its structure was designed.The structural dimensions of key parts were parameterized.Aiming at the working environment of laying the angular invariable inclined track,the design scheme of the shuttle bus is put forward,and the structure of the conversion equipment used for the horizontal track and inclined track is designed.In order to ensure the safety of the two types of chassis,the stability analysis and calculation are carried out respectively.Secondly,this paper develops the computer-aided design system of the X-shaped chassis.On the basis of the structural design,we establish the corresponding database of the chassis and model library.This design system takes Visio Studio 2010 as the development platform,through selecting the type of the chassis,inputting the main design parameters,connecting the model base and the database by C# language,and using the dimension-driven method to generate the parametric design model in Solid Works software.The development of this system will program the design process of the new underframes of BMU.At last,this article introduces the finite element analysis process of x-frame and shuttle bus in ANSYS software.It mainly includes the explanation of the simplification of solid model,the establishment of finite element model,the application of constraint load and the analysis of solution.We verify the rationality of the structural design by analyzing the stress and displacement nephogram.The structural design of the new-type underframe of BMU solves the shortage of the domestic common "well" underframe in some working conditions,and provides a new idea for the design and development of the roof track type BMU.The development of parameterized design system of chassis greatly improves the efficiency and accuracy of chassis design,reduces the production cost and shortens the design cycle.At the same time,the idea and method of parametric design can be used for reference in the design of similar products.