This paper proposes a high-effective fault-tolerance double-stator magnet-less vernier (DSMV) machine for direct-drive robotics. By virtue of the integration of DC-winding excitation, double-stator structure and vernier topology, the DSMV machine acconu11odatcs the merits of cost-effectiveness, high flux controllability, adequate torque density under low-speed operation and low torque ripple to 3.90%. Moreover, through the fault-tolerance operation, the torque perfonnanc3s of both one-phase and two-phase deficiencies recover to the normal level, with torque ripple slightly deteriorated. Both theoretical derivation and demonstration arc given for the validation of the DSMV machine design and the high-effective fault-tolerance operation. Machine Design and Fault-Tolerance Operation Principle presents the topology of the proposed DSMV machine, in cross-section and exploded perspectives. The double stators accommodate 18 split flux modulation poles (FMPs), with 24-polc segmented rotor in the middle. Polyester is embedded between rotor irons as fixation. Two sets of concentrated armature windings arc allocated in the embedded slots, while DC-windings arc coiled in series-opposing connection on FMPs.