Research On The Optimization Method Of Attitude Adjustment Of A New Semi-Submersible Rescue Robot In Water

In recent years,accidents involving people falling into water have occurred from time to time,posing a great threat to people’s lives and property safety.In view of the narrow scope of application and low rescue efficiency of the existing water rescue equipment,a new semi-submersible rescue robot is designed,and a rescue robot spatial attitude adjustment optimization method based on dynamic planning algorithm is proposed,and the robot experiment is verified.(1)To address the attitude adjustment problem of the rescue robot in the rescue process,the equation for estimating the initial stability height of the robot under no load and under the influence of free liquid surface is derived based on the principle of ship statics.The robot’s transverse inclination angle,longitudinal inclination angle,the maximum water level of ballast water tank and the maximum mass of pre-ballast water are taken as the constraints for the safe operation of the robot,and the foundation is laid for the establishment of an optimized mathematical model.(2)An optimization method of spatial attitude adjustment of the rescue robot based on dynamic planning algorithm is proposed to improve the efficiency of robot spatial attitude adjustment.According to the rescue mode of the robot to salvage the fallen person,the whole continuous process of salvaging and rescuing the fallen person is divided into several stages,and the optimal mathematical model of ballast water deployment of the rescue robot is established with the amount of change of the average water level in each ballast water tank during the rescue process and the ballast water pre-ballast quality before the rescue as the optimization variables and the shortest ballast time as the optimization objective.(3)The optimized solution is solved based on the data of an empirical solution of simulating the rescue of a common kind of fallen person under the guidance of a senior engineer from the North Sea Rescue Bureau of the Chinese Ministry of Transport.The calculation results showed that the total ballast water deployment time and total deployment mass were reduced by about 11.07% and 30.79%,respectively,and the stability of the variation of the cross-tilt angle and longitudinal tilt angle were improved by about 4.18% and 8.67%,respectively.(4)The weight,center of gravity height and initial stability height of the robot under no load were estimated,and the robot attitude adjustment processes under the empirical and optimized schemes were experimentally verified.The analysis of the results shows that the overall fluctuations of the robot’s transverse and longitudinal inclination angles under the empirical and optimized schemes are stable at about 3～5°and 2～3°,respectively,which verifies the effectiveness of the optimized mathematical model proposed in this paper.In summary,this paper solves the problem of low spatial attitude adjustment efficiency of the new semi-submersible rescue robot,and provides theoretical guidance and technical support for the realization of fully automatic and efficient ballast control.