Mobile Robot For Navigation In Residential Area Of Mildly Retarded Elderly

Since the 21st century,China's aging problem has become more and more prominent,and the proportion of the elderly suffering from Alzheimer's disease is also increasing.With the young people going out to work,the labor cost of the service industry is expensive,and the phenomenon of the elderly living alone and empty nesters appears.Therefore,the elderly accompanying robots on the market emerge as the times require,but most of them are indoor accompanying robots.Therefore,aiming at the simple environment in the community,this paper takes the ROS based mobile robot as the specific research object,and carries out the research and experiment on the autonomous navigation of mobile robot.(1)The kinematics model of Ackermann transformation mobile robot is deduced from the simple vehicle model.At the same time,the software and hardware system based on ROS robot operating system is built to realize the functions of robot motion control,self-state detection,external environment perception,map construction and navigation.(2)Based on the study of the global path planning algorithm,the traditional d*Lite algorithm,the following improvements are made to solve the problems of imprecise heuristic value and oblique crossing obstacle grid:a more accurate calculation distance is used to replace Chebyshev distance as the heuristic value to realize the distinction between straight line distance and oblique line distance;The dangerous nodes are introduced into a safety factor to realize the classification of extended nodes;The computer simulation of the improved algorithm is completed.The simulation results showed that the improved d*Lite algorithm has better performance because of more accurate heuristic value,less expansion times and better performance;By introducing the safety factor,the dangerous nodes would not be the first choice of the path,which solves the problem that the planned path slants through the grid vertices of obstacles,and makes the pre-planning stage and re-planning stage achieve very safe path planning;DWA algorithm is used to optimize the motion of the car,and MATLAB software is used to simulate,which improves the stability of the robot motion.(3)Through the establishment of the navigation system based on the ROS robot operating system,the real environment experiments are carried out in the static environment and dynamic environment to verify and analyze the path planning algorithm designed in this paper.The experiments showed that the robot can safely and real-time avoid the static and dynamic obstacles in the environment,quickly and smoothly reach the designated target point,So as to verify the effectiveness of the path planning algorithm designed in this paper.