Shock absorber

A shock absorber that is attached to an attachment target constituting a vehicle and reduces a shock during operation, the shock absorber, comprising:

• a base portion fixed to the attachment target;
• a shock absorbing portion having flexibility and attached to the base portion, the shock absorbing portion being reversibly switchable between a housed state in which the shock absorbing portion is retracted toward the base portion and a protruding state in which the shock absorbing portion protrudes from the base portion;
• and
• a drive unit configured to drive the shock absorbing portion and reversibly switch between the housed state and the protruding state, the drive unit at least switching the shock absorbing portion from the housed state to the protruding state when operating the shock absorption portion,
• wherein the shock absorbing portion includes a plurality of shock absorbing members provided in a plurality of columns, the plurality of shock absorbing members each being rotatably attached to a first pivoting axis of a plurality of first pivoting axes that extend in a first direction relative to an installation surface of the base portion and are spaced apart from each other in a direction orthogonal to the first direction,
• each of the plurality of shock absorbing members provided in the plurality of columns is:
• maintained in a falling down orientation along the installation surface in the housed state;
• rotated and driven in a predetermined activating direction about the first pivoting axis and switched from the falling down orientation to a standing orientation in which each of the plurality of shock absorbing members is erected from the installation surface, when being switched from the housed state to the protruding state;
• and
• rotated and driven in the falling down direction opposite to the activating direction about the first pivoting axis and switched from the standing orientation to the falling down orientation, when being switched from the protruding state to the housed state.