Characterising robot environments

A robotic system comprising:

• a first and second robot, each comprising:
• a base;
• a flexible arm extending from the base and having a plurality of joints whereby the configuration of the arm can be altered;
• a plurality of drivers arranged to drive the joints to move;
• and
• a plurality of position sensors configured to sense the position of each of the joints;
• wherein the first robot further comprises a first datum carried by its arm and the second robot comprises a second datum, the first and second datums being mutually configured so that the orientation of the first datum is fixed and known with respect to the second datum when the datums are mated;
• and the first robot further comprises a control unit configured to:
• (i) calculate, in dependence on the outputs of the position sensors when the first datum carried by the arm of the first robot is mated with the second datum on the second robot, a position of the second robot relative to a reference location defined in a frame of reference local to the first robot and an orientation of the second robot relative to the first robot;
• and (ii) subsequently control the drivers to reconfigure the first arm in dependence on at least the calculated position and orientation.

A robotic system comprising:

• a first and second robot, each comprising:
• a base;
• a flexible arm extending from the base and having a plurality of joints whereby the configuration of the arm can be altered;
• a plurality of drivers arranged to drive the joints to move;
• and
• a plurality of position sensors for sensing the position of each of the joints;
• wherein the first robot further comprises an interface carrying a first datum;
• a second datum comprising an interface in the shape of a proximal instrument or endoscope end, the first datum and the second datum being mutually configured so that when the first datum mates with the interface of the second datum the orientation of the first datum is fixed and known with respect to the second datum and the second datum has a known relationship to the second robot arm;
• and
• a control unit configured to:
• (i) calculate, in dependence on the outputs of the position sensors of the first robot arm when the first datum and the second datum are mated, an orientation and position of the second robot relative to the first robot;
• and (ii) control the drivers to reconfigure at least one of the first and second robot arms in dependence on at least the calculated orientation and position.