A method for controlling movement of a robot having a plurality of links connected by rotatably driven joints includes the steps of: a) defining a target speed vector of a reference point of the robot in Cartesian space; b) determining rotation speeds ({dot over (q)}.sub.ref) of the joints which minimize a weighted sum, the weighted sum having for summands i) a discrepancy (∥{dot over (x)}.sub.ref.sup.k−J{dot over (q)}.sub.ref.sup.k∥.sub.W.sub.x) between the target speed vector ({dot over (x)}.sub.ref) and an actual speed vector ({dot over (x)}.sub.act) calculated from actual rotation speeds of the joints; and ii) a rate of change $\left(\frac{1}{T_S}{.Math.{\stackrel{.}{q}}_{\mathrm{ref}}^k-{\stackrel{.}{q}}_{\mathrm{ref}}^{k-1}.Math.}_{W_a}\right)$
of the target rotation speeds; and c) setting the rotation speeds ({dot over (q)}.sub.ref) determined in step (b) as target rotation speeds of the joints.

A fractional order Linear Active Disturbance Rejection Control (FOLADRC) system and a method thereof is disclosed. The FOLADRC system includes a fractional order state extended observer (FESO) controller circuit having a FESO controller. The FESO controller receives a process variable and plant output signal, estimates an input disturbance and an output disturbance and outputs disturbance cancelling feedback signals. The disturbance cancelling feedback signals are transmitted to multipliers present in a forward path of the FESO controller circuit. Further, the FESO controller has an observer gain vector and a cross over frequency bandwidth. The FESO controller incrementally changes the observer gain vector and the FESO controller bandwidth until a closed loop transfer function of the FESO controller converges, thus exhibiting an iso-damping property.

A method for controlling movement of a robot having a plurality of links connected by rotatably driven joints includes the steps of: a) defining a target speed vector of a reference point of the robot in Cartesian space; b) determining rotation speeds ({dot over (q)}.sub.ref) of the joints which minimize a weighted sum, the weighted sum having for summands i) a discrepancy (∥{dot over (x)}.sub.ref.sup.k−J{dot over (q)}.sub.ref.sup.k∥.sub.W.sub.x) between the target speed vector ({dot over (x)}.sub.ref) and an actual speed vector ({dot over (x)}.sub.act) calculated from actual rotation speeds of the joints; and ii) a rate of change

[00001]$\left(\frac{1}{T_S}.Math.{.Math.{\stackrel{.}{q}}_{\mathrm{ref}}^k-{\stackrel{.}{q}}_{\mathrm{ref}}^{k-1}.Math.}_{W_a}\right)$

of the target rotation speeds; and c) setting the rotation speeds ({dot over (q)}.sub.ref) determined in step (b) as target rotation speeds of the joints.