According to some embodiments of the invention, a surgical robot includes a robot arm having an end effector, the end effector comprising a needle assembly. The surgical robot further includes a robot control system operatively connected to the robot arm, and an end effector control system operatively connected to the end effector. The robot control system provides control signals for operation of the robot arm to move the end effector to selected positions relative to a subject. The end effector control system is configured to provide signals for operation of the end effector to at least one of inject material through the needle assembly to a selected location within the subject's body or extract material through the needle assembly from the selected location within the subject's body.