Strain wave gearing and drive arrangements

A drive arrangement for manipulating a vehicle control surface, the drive arrangement comprising:

• a first drive;
• a second drive;
• an output member for connecting to the vehicle control surface;
• one or more first engaging components for selectively engaging and disengaging the first drive and the output member;
• and
• one or more second engaging components for selectively engaging and disengaging the second drive and the output member;
• wherein the one or more first engaging components comprise a strain wave-type gearbox, the strain wave-type gearbox including
• a flex spline component,
• an outer circular spline component, and
• a wave generator component configured to cause lengthening and shortening of a major axis of the wave generator component;
• wherein when the major axis of the wave generator component is in a lengthened configuration, the wave generator component causes engagement of the flex spline component and the outer circular spline component;
• and
• wherein when the major axis of the wave generator component is in a shortened configuration, the wave generator component causes disengagement of the flex spline component and the outer circular spline component.

A drive arrangement for manipulating a vehicle control surface, the drive arrangement comprising:

• a first drive;
• a second drive;
• an output member for connecting to the vehicle control surface;
• one or more first engaging components for selectively engaging and disengaging the first drive and the output member;
• and
• one or more second engaging components for selectively engaging and disengaging the second drive and the output member;
• wherein the one or more first engaging components comprise a strain wave-type gearbox, the strain wave-type gearbox including
• a flex spline component,
• an outer circular spline component, and
• a wave generator component including a mechanism arranged to cause lengthening and shortening of a major axis of the wave generator component,
• wherein when the major axis of the wave generator component is in a lengthened configuration, the wave generator component causes engagement of the flex spline component and the outer circular spline component, and
• wherein when the major axis of the wave generator component is in a shortened configuration, the wave generator component causes disengagement of the flex spline component and the outer circular spline component.