RIGIDITY ADJUSTING MECHANISM

1 . A rigidity adjusting mechanism comprising:

a base;

a first columnar member fixed at one end onto the base and extending at other end to a predetermined direction;

a second columnar member fixed at one end onto the base, adjacent to the first columnar member, extending in parallel to the first columnar member, and having higher rigidity than the first columnar member;

a connection member movable to a desired position, in the longitudinal direction of both first columnar member and second columnar member, and connecting the first columnar member and the second columnar member; and

a fixing section that fixes the connection member onto a desired position in the longitudinal direction.

2 . A rigidity adjusting mechanism according to claim 1 , wherein each of the first columnar member and the second columnar member has a guidance section that guides a movement of the connection member in the longitudinal direction.

3 . A rigidity adjusting mechanism according to claim 1 , wherein the rigidity adjusting mechanism further comprises:

a driving section that drives the connection member to a desired position in the longitudinal direction;

a sensor that detects a position of the connection member; and

a rigidity control section that drives the driving section in accordance with information from the sensor to move the connection member so that rigidity of the first columnar member is controlled.