A surgical robot can be configured for minimally invasive surgery (MIS) and other types of surgery with modular link geometry and disposable components. In some examples, the surgical robot includes a cable driver comprising at least one drive motor configured for tensioning a cable. The surgical robot includes an articulated surgical tool coupled to the drive motor by the cable. The articulated surgical tool comprises at least first and second articulated links and a joint coupling the first and second articulated links. The cable passes through the joint, and the joint comprises an elastic antagonist biased in opposition to tension from the cable to allow bidirectional actuation of the joint. The surgical robot includes a safety lock configured to lock the joint from allowing articulation of the first and second articulated links in response to a loss of tension in the cable.
