Patent ID: 7953561

Claim:
An apparatus for applying at least one cyclical load to a specimen, the specimen extending at least along a longitudinal axis, comprising: a mass; an actuator mounted to the specimen and operatively associated with said mass, said actuator moving said mass along a linear displacement path that is perpendicular to the longitudinal axis of the specimen, wherein the specimen comprises a wind turbine blade that is rigidly mounted at a root end and unsupported at a tip end and wherein the actuator is mounted at a location between the root end and the tip end of the specimen such that the moving of the mass relative to the wind turbine blade applies a bending load to the specimen; and a control system operatively associated with said actuator, said control system operating said actuator to reciprocate said mass along the linear displacement path at a reciprocating frequency, said reciprocating frequency being about equal to a resonance frequency of the specimen in a test configuration causing displacement of the tip relative to the longitudinal axis of the specimen.