Design of a Robotic Rowboat

This paper presents the design of a minimally actuated robotic rowboat. A spherical four-bar mechanism is used to move an oar around the center of a sphere located at the oar lock. One servo-controlled actuator for each side provides the desired rowing motion to drive and steer the rowboat. The dimensions of the spherical four-bar linkage that achieves the desired trajectory for the oar blade are computed using the kinematic synthesis technique known as motion generation. This paper provides the linkage design equations for five task orientations and describes the digital and physical prototypes that implement this design into a robotic rowboat to demonstrate the operation of the oar linkages.