Research On Innovation Of The Ladder For Concrete Mixer Truck Based On Situations

Product design should not only realize the basic functions of the product,but also meet the physiological and psychological needs of users in the use scenario.At present,although the ladder at the rear of the concrete mixer truck has achieved basic functions,for example,observing the inside of the tank,cleaning the height of the rear of the mixer and adding auxiliary materialsthe,many problems still has during use.For example,climbing up and down the ladder is easy to rub against the wheel stains,the ladders are easy to be hit and deformed when the mixer truck passes through the narrow space,and climbing angle,height cannot be adjusted by operator and poor safety and laboriousness of users climbing stairs.Therefore,it is necessary to develop new ladders for concrete mixer trucks to solve the problems of existing ladders.First of all,according to user needs to obtain the process,based on the analysis of the components of the use situation of the ladder of the concrete mixer truck,using the scenario design method to build a story board for the use of concrete mixer truck ladders,based on which the potential needs of the users of the mixer truck ladders are tapped.Using the KJ method to finish user needs,and conduct expert evaluation tests on the finished user needs.Principal component analysis is performed on the test data,and SPSS software is used to process the data to construct a user demand model.According to the relative importance of the demand items in the user demand model,a story board for the future use of the ladder of the mixer truck is designed.Secondly,according to the design steps of the product principle plan,based on the collection of samples of ladders and related products,multiple representative samples of ladders were selected using multi-scale method and cluster analysis method.Applying a systematic method to analyze the functional structure of typical samples of ladders respectively to obtain their functional hierarchy(functional tree),functional structural diagram and functional meta-carrier.On this basis,the morphological matrix method is used to synthesize the new functional principle scheme of the ladder of the mixer truck,and several functional principle schemes with high feasibility are selected.Aiming at the typical samples of the ladder shape,the SD semantic difference method is used to determine therepresentative vocabulary of the sensibility image of the ladder shape based on the evaluation of multiple people.Based on this,the design of he mixer truck ladder appearance modeling scheme is proposed.Third,according to the evaluation index system of the electromechanical product program,on the basis of expert evaluation,using the direct skew method of SPSS software to perform factor analysis on the evaluation indicators to determine the index items suitable for the evaluation of the satisfaction of the ladder climbing scheme of the concrete mixer truck.Further use information entropy,AHP method to determine the relative weight of each evaluation index item.Triangular fuzzy number multi-attribute group decision-making method is used to screen the functional principle scheme and appearance modeling scheme of the innovative ladder to determine the optimal scheme.Finally,using Creo and keyshot software,three-dimensional modeling and appearance modeling effect expression of the preferred ladder plan for concrete mixer trucks,and virtual simulation of its use process.It shows that the innovative design of the concrete mixer truck program is feasible and well meets the needs of users.