Silva, ManuelTenreiro Machado, J. A.Lopes, A. M.2019-04-092004-120924-090Xhttp://hdl.handle.net/10400.22/13493This paper studies the performance of integer and fractional order controllers in a hexapod robot with joints at the legs having viscous friction and flexibility. For that objective the robot prescribed motion is characterized in terms of several locomotion variables. The walking performance is analysed through the Nyquist stability criterion and several indices that reflect the system dynamical properties. A set of model-based experiments reveals the influence of the different controller implementations upon the proposed metrics.engHexapod robotPD controlCascade controlSaturationFrictionFlexibilityFractional-order controljournal article10.1007/s11071-004-3770-8