A minimally invasive system using a surgical robot as a three-dimensional printer for fabrication of biological tissues inside the body of a subject. A preoperative plan is used to direct and control both the motion of the robot and the robotic bio-ink extrusion. The robotic motion is coordinated with the ink extrusion to form layers having the desired thickness and dimensions, and use of different types of ink enables composite elements to be laid down. Such systems have a small diameter bio-ink ejecting mechanism, generally in the form of a piston driven cannula, enabling access to regions such as joints, with limited space. The robotic control is programmed such that angular motion takes place around a pivot point at the point of insertion into the subject. The bio-inks can be stored in predetermined layers in the cannula to enable sequential dispensing from one cannula.
