Research On Indoor Path Planning Of A Transfer Robot For Nursing Care

In order to solve the transfer problem of the disabled elderly with lower limbs and help the disabled elderly realize the movement between beds,wheelchairs,sofas,toilets and other living appliances in the family environment,the indoor intelligent transfer nursing robot needs to complete from any starting point,any starting position,to deliver the human collision-free,safe to the target point,and complete the robot head-to-tail forward in the transport process.Tasks such as transition require the ability of path planning for robots.In view of this,this paper adopts the piecewise path planning method,through the appropriate selection of the middle transformation position and pose,the turning angle range of the robot in limited indoor space has been effectively improved,and the number of adjustments and the distance of travel have been significantly reduced.At the same time,on the basis of VFH algorithm,the dynamic obstacle avoidance ability is improved.Finally,the effectiveness and practicability of the proposed method are verified by experiments.In this paper,the experimental platform is based on a humanoid backpack transfer nursing robot.Firstly,the functional module and control system design of the robot are introduced,its motion model is established,and its mathematical models of linear motion,arc motion and rotation motion are analyzed.In the ROS system,the navigation frame is built,and the planning nodes in the upper computer and the driving nodes in the lower chassis are established.The sensor is analyzed and its role in the process of robot motion is studied.Then,a motion mode that meets the functional requirements of the robot is proposed.In the whole movement process,an intermediate position and posture point is found,and the motion process is divided into two continuous path planning processes.Global path planning A* algorithm and local path planning VFH algorithm are studied.In order to improve the dynamic obstacle avoidance ability of VFH algorithm,the grid partition,histogram construction and threshold determination are improved.Secondly,the selection of the middle point posture is introduced.By choosing reasonable coordinates to simplify the complexity of the path,at the same time,the reasonable angle of the middle point is selected to reduce the number of posture changes in the process of motion.Finally,the slip error in the process of converting the middle position and attitude points is analyzed,and the error is improved by controlling the speed parameters to make the whole process more stable.To improve the smoothness of the trajectory curve,the trajectory control and turning radius of the robot during steering are studied,and the parameters of the robot motion are adjusted to make the trajectory smoother and improve the comfort of the motion process.The rationality of the robot path planning method is verified by experiments.The motion process of the robot is simulated by the simulation software,and the motion path is analyzed to verify the rationality of the motion mode.Experiments were carried out on a real robot platform to record the adjustments of position and pose,the movement time and distance,and to analyze the data to verify the effectiveness of the path planning model.