Hierarchical fuzzy control for autonomous navigatio of heeled robots

The autonomous navigatio heeled robots ( R) requires integrated kinematic and dynamic control to perform trajectory tracking, path follo ing and stabilisation. Considering a R is a nonholonomic dynamic system ith intrinsic nonlinearity, unmodelled disturbance and unstructured unmodelled dynamics, fuzzy logic system based control is appropriate and practical. Ho ever, the multivariable control structure of the R results i the curse of dimensionality of the fuzzy desig and prevents a domai expert from building the linguistic rules for autonomous navigation. Hierarchical fuzzy desig decomposes the controller into three lo -dimensionality fuzzy systems: fuzzy steering, fuzzy linear velocity control and fuzzy angular velocity control, so that manual constructio of each rule base becomes feasible and easy. The proposed design enables a R to perform positio control i trajectory tracking and velocity profile tracking i continuous drive. The coupling effect bet ee linear and angular motion dynamics is considered i the fuzzy steering by building appropriate linguistic rules. To facilitate the autonomous navigatio desig and verification, a prototype and the model of a kind of R have bee developed, and equipped ith the hierarchical fuzzy control system. The simulatio and experimental results are sho and compared.