Lightweight Analysis And Optimization On Heavy-duty Commercial Truck Cab

Accompanied by the emergence of the energy crisis and global warming issues,Vehicle weight reduction is a hot topic. Reduce the curb weight of the car, not onlycan reduce a car’s fuel consumption and reduce emissions of harmful substances, butalso can improve the car loading or patronage to improve the efficiency of automobilemotor transport. The Lightweight analysis of the vehicle structure can be startedwiththe using of light materials, new processing method and structureoptimization.Structural lightweight design is the most important approaches of vehicle lightweightanalysis, it is the basis and prerequisite for lightweight automotive productdevelopment. Through the lightweight design, we can not only use the suitablematerial, shape and size of the optimal structure at suitable position in automotivestructures, so that every part of the material play its right role such asloading,energy-absorbing and stiffness improving, but also can improve material utilizationand reduce vehicle weight,material costs and emission, saveenergy.According to the major projects of the Provincial Science and TechnologyScience and Technology Development Plan "Lightweight Analysis and ApplicationsofCommercial VehicleCab ", this paper performed deeply theoretical analysis andexperimental research on lightweight design, evaluation methods and itsapplicationsystems of heavy-duty commercial vehicle cab.Through the lightweightdesign and testing of heavy commercial vehicle cab white body structure to achievegood weight reduction results.Firstly, using the finite element method, some FEA models of white Cab werebuiltto perform modal analysis, strength, stiffness and passive safetyanalysisrespectively. The natural vibration characteristics of the cab in the free statewas analyzed, the maximum dynamic load on the cab was determined as the heavy commercial vehicles in the four typical operating conditions steering,braking,acceleration and driving straight. The strength and stiffness analysis were performedunder the above four operating conditions.Based on ECE R29regulations, the cabpassive safety analysis and evaluation was made on front pendulumimpact, roofstrength and rear wall strength,toprovide a reference for comparative analysis of cablightweight design and improvement.Applying topology optimization and topography optimization methods,lightweight design of white cab structure was performed and the lightweight plan wasdetermined. According to the strength, stiffness, vibration characteristics and passivesafety finite element analysis results on lightweight white cab and thecompartmentswith the original cab performance, the performance of the lightweight white cab wasverified.A new proposal of using lightweight coefficient as lightweight evaluatingmethod was made, and had been used to analysis and evaluates the lightweight levelof the white cab.In order to assesswhether the lightweight design can meet the operatingrequirements, we developed a lightweight cab sample, measured the first10elasticmodal frequencies and mode shapes and their static bending and torsional stiffnesscharacteristics of the lightweight cab; the first torsional frequency and stiffnesscharacteristics were analyzedand compared between the original and lightweight cab.Although lightweight cab first torsional frequency and static bending and torsionstiffness decreased, but the first torsional frequencywas larger than16Hz, the bendingstiffness>14000N/mm and torsional stiffness35000Nm/°, which meaned that itcan meet the driving chamber stiffness and vibration characteristics requirements.Based on ECE R29Regulatory requirements, lightweight cab passive safetysimulation analysis and experimental research were performed, the results showedthat the lightweight cab can meet the ECER29regulatory requirement of frontpendulum impact, roof strength and rear wall strength.The8000km road test results showed that the lightweight cab performed well during the test, the lightweight cab reliability can meet the reliability requirements.After lightweight analysis and optimization, the cab reduced weight46kg in thecase of maintaining the same material and meeting the operating requirements.Proposed and developed a frame-type lightweight commercial vehicle cab,optimized the structure and size of the cab frame, performed the model state analysis,strength, stiffness and passive safety analysis of the cab frame, and compared thecorresponding characteristics withthe original cab; The results showed that thedeveloped frame-type lightweight cab significantly improved the strength andstiffness, superior vibration characteristics, and can better meet ECER29passivesafety requirements. It was lighter95kg than the original cab.The cab developed in this paper has been used for the production and sales ofheavy commercial vehicle cab and got good weight reduction and energy-savingeffect. The research results can be widely used as a common technology lightweightdesign on different commercial vehicle cab and play an important role to improvethe forward design capabilities of domestic heavy commercial vehicle cab,implementthe energy saving and emission reduction, enhanced competitiveness in internationalmarkets and promote industry technological progress.