Provided is a fixed point mechanism. In the fixed point mechanism, when a drive torque acts on a first connecting rod member (100) or a slide block device (110), the fixed point mechanism can realize a rotation movement around a fixed point； when a drive torque acts on a fourth connecting rod member (103) or a sixth connecting rod member (105), the fixed point mechanism can realize a telescopic movement relative to the fixed point； and when a drive torque acts on the first connecting rod member (100) or the slide block device (110), and another drive torque acts on the fourth connecting rod member (103) or the sixth connecting rod member (105), the fixed point mechanism can realize a rotation movement around the fixed point and a telescopic movement relative to the fixed point. That is, the fixed point mechanism has two degrees of freedom of the rotation movement around the fixed point and the telescopic movement relative to the fixed point.
