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Based on the platform of trolley equipment, this paper used a liquid containing gas as a sensor to establish a new testing method in order to simulate the mechanism of contre-coup injury during head decelerating impact. After pouring the liquid containing gas into the transparent skull model, the head model was sealed and fixed to the trolley. Then the trolley was trigged to impact the counterguard as the speed of 50km/h, the impacting course was recorded by a high-speed camera at the same time. Finally, the movement of the gas in the liquid during the impact was analyzed using the sequence pictures analyzing software as to ensure the area of negative pressure which appeared during the impact. The results showed that in the head decelerating impact the negative pressure can appear at the contre-coup site. This denoted that in the traffic accidents brain tissue of driver or passengers may suffer from tension injury at the contre-coup point. This paper provides a new equipment and method to research the biomechanical mechanism of contre-coup injury in traffic accidents which is helpful to understand the distribution of negative pressure in brain tissue during head decelerating impact.

Upper limb fracture is easily found in the truck-to-pedestrian road traffic accident. And it is important to understand and elucidate the biomechanics of upper limb fractures caused by the frontal structure of the truck. Finite element (FE) analysis could potentially help in the understanding the biomechanical response mechanism of upper limb fracture. In this study, THUMS (Total Human Model for Safety) was applied to reconstruct the upper limb fracture in a real-world truck-to-pedestrian accident. Totally two FE simulations were conducted to find out the most likely scenario in this case. Analyzing the simulations of two possible scenarios clearly demonstrated that the simulation result of collision-to-left scenario was consistent with the autopsy finding, and bending mechanism could explain how the upper limb fracture occurs. Then we drew a conclusion that FE analysis is a valuable method for us to understand the biomechanical mechanism of upper limb fracture in the forensic practice.

s: Brain impact injury is the leading cause of death in traffic accidents. In this paper, a brain multi-functional rotary impacting platform will first be set up. After this, the living animal brain sagittally rotary impacts will be executed and the injury tolerance will be achieved. Then, the sagittal physical models of animal and human brains will be produced and the four-point markers will be placed widely on the models sagittal sections. In succession, the high-speed camera and the three-dimension infrared motion analysis meter will be used to record the rotary impacting process, the exterior angular acceleration course and the shearing strain data of interior four-point markers. Thus, with the exterior angular acceleration course, the living animals experiments and the experiments based on the animal physical brain model can be coupled equivalently. In the same way, through the maximum shearing strain data of interior four-point markers, the experiments based on the animal physical brain model can be equivalently coupled with the experiments based on the human physical brain model. Finally, according to the comparability in pathology and physiology between animal and human brain tissue, the injury tolerance of human brain under its sagittally rotary impacts can expect to be obtained through the mechanics study.

It set up a quick and high accurate method of 3D measurements from the 2D digital photogrammetry to reconstruct the scene by teleprocessing. Three types of feature marks in the matrix arrayhave been projected. The calibrations of the camera with fixed focal length have been calculated and compared before and after revision. The cross-shaped feature was the most accurate mark. And the cone barrel with sharp apex was also more accurate than the traditional round dot. The real case practices have been engaged in to verify the practicability and efficiency of the projects. In less than 10m with 6 points, the maximal error has been reduced to 0.029%. In around 20m with 20 to 34 ponits, the maximal error has been reduced to 0.046%. And it was far more accurate than the counterpart research (0.44%).The measurements results of the more big areas have been found to be instability. So the lawful choice of the single photogrammetric image scope should be limited to 20m. In the proper image scope (