The Navigation And Control Of Biomimetic Snake Robots

In the past few decades,the hardware and software of snake robots have gained a great amount of development,shaping snake robots into biomimetic appearances and applying more snake gaits into snake robots.However,limited to some factors,only few applications of snake robots were invented.Hence,this thesis makes a snake robot with some functions,such as trajectory tracking,pipes traversing and exploration.Furthermore,exploration system is devised to plan an exploration goal for the snake robot and direct it approach the goal iteratively until the whole unknown environment which the snake robot first enters is mapping.Consequently,the decision module of determining the exploration goals has a great influence on the efficiency of exploration system.Hence,this thesis proposes a new algorithn in order to enhance the efficiency.Final,this thesis proves the effectiveness of the snake robot system via experiments,meanwhile,proves the proposed decision algorithm is more effective compared with two representative algorithms.This research focuses on navigation and control of snake robots,referring to some papers of biomimetic locomotion field and exploration mission.Furthermore,this thesis designs a model-free controller,called Fuzzy logic controller.Finally,the exploration function is achieved based on these work.The main research work is described below:First,the choice of the serpentine locomotion generator of the snake robots.Design of the locomotion of the Snake robot is based on a bionic view while snakes generate locomotion via rhythmic bending of stretching of their muscles.Thus,this part of work refers the physics and dynamics of snake locomotion in order to construct the snake robot.Besides,serpentine locomotion is the most common snake locomotion.Hence,this part choose to apply this locomotion into the snake robot via a locomotion generator.Furthermore,accord;ing to the selected locomotion generator,this part need to seek control variables which can influence the speed and direction of the snake robot.Second,the closed-loop control of trajectory of the snake robot.Based on the selected locomotion generator,this part endows the snake robot with an ability of tracing a desired trajectory.In details,this ability means that the snake robot can start moving from a place in an environment,gradually approaching and tracing the desired traj ectory until approaching the destination designed previously.Third,the control system of traversing a narrow pipe.Localization is one of most vital abilities which supports the survival and growth of creature herds.It bases on establishment of a coordinate and subsequently enables creature herds to handle complex tasks in the coordinate.This part employs strapdown sensors to localize poses of the snake robot during experiments,meanwhile,devises a path planning algorithm constantly to produce paths which the snake robot should trace.Finally,the poses and paths are relayed to the closed-loop controller designed in the last mission to calculate the corresponding control variable which direct the snake robot consequently traverse the pipe.Fourth,the exploration function which enable the snake robot to plan the next exploration goal and approach it iteratively until the whole unknown environment which the snake robot first enters is mapping.This part is mainly aimed to devise a more efficient mechanism of assigning exploration goals to reduce the time cost to explore the whole unknown environment.Overall,the exploration function designed by this thesis carries out a lot of investigations in the field of system integration of snake robots,meanwhile,provides a kind of application of snake robots.