Gait Planning Methed For Hexapod Robot Based On CPG Rhythm Generator Network

Leg-type robot which has good mobility and lower energy consumptioncompared to crawler and wheeled robots can adapt to rugged structure of the groundand overcome obstacles. Leg-tpye robot research contains three directions, such asquadruped robot, hexapod robot and spider robot. Hexapod robot possesses morestable character than qudruped robot and more flexible control than spider robot,therefor the purpose of this thesis is aimed at the study of a hexapod robot, whichfouce on gait, control strategy and obstacle avoidance.The three types of gait including triangle gait, quadrupedal gait and wave gaithave been analysed with respect to characteristics and stability, and the relationshipbetween gravity center of robot and the corresponding support polygon as well asforward kinematics has been calculated using six polynomial contraints and quinticploynomial contraints to plan foot end swing trajectory curve and support trajectorycurve.In order to achieve rythmic control for legs during walking this researchconsiders the Matsuoka mathematical model which is fourth-order non-linearcoupled system model with strong coupling, high-dimensional and multi-variablecharacteristics as CPGs(Central Pattern Generators) control model. And theapproximate relationship between the waveform output and model parameters isderived by Fourier trigonometric series in which the observation method and phaseplane method are used to analyse and modify parameters. Relate to the controlstrategy, establish mapping between the output signal and range of motion ofsteering gear of robot’s leg joints and employ the offline method to test thefeasibility of output. Subsequently, complete the topology control structure ofoverall CPGs oscillator on robot. Finally, in order to e valuate the driving torque ofjoint when the hexapod robot moves according to the planning trajectory, jointtorque of robot has been measured through the model of robot which is built byADAMS.Overcoming the obstacle is the key issue in hexapod applation which has beensolved by quadratic programming standing for programming again from breakpoint.At last, the tripod gait and quadrupedal gait controlled by CPGs network andsearching gait designed by quadratic programming have been verified.