The picture shows a static test on a rotor blade. Loading is done by servohydraulic actuators with strokes of up to 10 m. Tip deflection of up to 20 m is done by translating the stroke using a pulley gear ratio 1:2.
In total five actuators are involved in bending the rotor blade.
Special Inova developed hydraulic circuits ensure safety even in case hydraulic power fails. In this case a special unloading procedure is started to release the energy from the bent blade.
Photo by Fraunhofer IWES