Research On The System Of Vehicle Acceleration Of Safety Belt

With the rapid development of China's automobile industry and people's increasing attention to travel safety,vehicle manufacturers and parts companies have put forward more and more stringent requirements on the quality and comprehensive performance of au safety belts.Foreign experts and scholars mostly study the structure of the retractor and occupant restraint,but the research on the detection of emergency locking performance of safety belts is a little insufficient.In this paper,according to the requirements of national standard for emergency locking of safety belts,the mechanical structure design and control system design of the testing equipment are carried out.Finally,a series of tests verify the rationality of the design,which provides reference value for the safety belt testing industry and has certain social benefits.The following is the main research content of this paper.(1)Development of mechanical structure system for performance testing equipmentAccording to the requirements of GB14166-2013 for the detection of the vehicle acceleration of safety belt,the weaving belt jig,rewinder jig,rotating platform,test platform and main frame of the equipment are designed by using ergonomics principle,SolidWorks and other computer-aided software.PARKER linear motor was used to drive the test platform,and the response is quick.The rotating platform is driven by stepping motor,which is easy to control.The initial test position and installation Angle of the safety belt can be adjusted during the vehicle acceleration test.ANSYS software is used to analyze the static and modal of the rewinder fixture.The mechanical part of the equipment can safely,smoothly and efficiently complete the vehicle sense experiment.(2)Measurement and control system design of the performance testing equipmentBased on the servo motion control theory of PC+control card and the digital PID principle,the measurement and control system of upper computer+lower computer is designed,which is composed of PARKER linear motor,F28M35H52C1 chip,42BYG250B-0151 two-phase hybrid stepping motor,OMRON PLC,control card and industrial computer.DSP core circuit and peripheral circuit are designed.AM26LV32 acquisition chip collects acceleration,force and displacement signals in real time at the acquisition frequency of 10000 times/second,and then amplification,median filtering and storage processing are carried out.PLC program and LabVIEW2014 prepared by the upper computer test program,can automatically judge the lock,test curve and results in the data playback interface display.(3)Experiment and analysisThe experiment process is controlled by enhua industrial computer.The sensor calibration and parameter setting are carried out before the test.Of type 4 volumes to the transmitter respectively after pulling Angle for 0 ° and 90 °,180 °,270 ° 0.3 g and 0.45 g,0.5 g and 0.6 g,0.7 g and 0.85 g,1.0 g and 1.2 g series experiment.The acceleration slope of the linear motor is adjustable within the range of 0g/ s-400 g /s,ensuring that the time to reach the set acceleration is within 25±5ms,and the control precision of the linear motor is 2%F.S.The measurement accuracy of the acceleration sensor is 0.01 g.The locking state is determined by the force sensor,and the measuring accuracy of the force sensor is 0.5%RO.The test proved that the vehicle sense detection equipment was designed scientifically,operated safely and stably,and met the requirements.The innovation point of this paper is the innovative research on the design of rewinder,webbing fixture,real-time acquisition of acceleration,force and magnetic ruler displacement signal,digital filtering of signal,LabVIEW software development and automatic judgment lock and other aspects.