Medical apparatus with a medical optical appliance and a holding device and method for operating the medical apparatus

Medical apparatus having

• a medical optical appliance,
• a holding device with at least two holding arms which are connected movably to one another with at least one degree of freedom of movement via a joint, and with an actuator which is connected to the two holding arms in such a way that a force can be exerted via the actuator between the two holding arms in the direction of the degree of freedom of movement, and
• a control unit, which comprises a first regulator for outputting a first control signal to the actuator via an adjusting element,
• wherein the medical optical appliance is mounted on the holding device,
• characterized in that
• the control unit comprises means for measuring a kinematic state on the joint and a second regulator for outputting a second control signal to the actuator via the adjusting element,
• and the control unit is configured in such a way that it can be set to a first operating state and to a second operating state,
• wherein, in the first operating state, the actuator is controlled in a position-regulated manner via the first regulator and the adjusting element as a function of the kinematic state measured on the joint, in such a way that a relative position between the two holding arms is maintained at least substantially independently of external or internal influences on the holding device or the medical optical appliance, and
• wherein, in the second operating state, the actuator is controlled in a force-regulated manner via the second regulator and the adjusting element, in such a way that a relative movement between the two holding arms is permitted.