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This paper presents a numerical model of the boat—oars—rower system in a three-dimensional multibody dynamics approach using the ADAMS commercial software. The system is composed of four main parts: a skiff, two oars and a rower. The boat and oar mechanical model takes into account all boat settings and kinematic constraints, thus permitting a sophisticated model personalization. The rower skeletal model is built in LifeMOD (an ADAMS plug-in) software. In the example, a skilled rower is modelled with 19 human segments and 18 human joints which are personalized to the rower using the 32 external anthropometric data of the GEBOD program. In order to focus the tests on the rower on boat model, simulations are performed with basic hydrodynamic models for a single degree of freedom for the boat at first and then three degrees of freedom are used to show the potential of the model. The model is driven with five command signals, three oar rotations, seat movement, and lower torso rotation. The computed boat velocity is in good agreement with on-water measurements and a sensitivity test consisting of small variations of rowing technique allows the authors to be confident of the ability of the model regarding future optimization studies.

This paper describes the hydrodynamic forces on oar blades and compares measured data with common models: one model using a normal force coefficient and the other using drag and lift coefficients. The data were obtained from tests in towing tanks on blades at reduced scale (typically 0.7). The measurement device can reproduce oar movements and measure the six components of the hydrodynamic efforts. These tests provide a better control, precision, and repeatability than measurements on water. The experimental modelling leads to defining the oar strokes using only the maximum rotation rate and an advance number, which can also be defined as basic efficiency. These movements are simplified but remain representative of the main characteristics of the unsteady working of oars. The measurements show how the direction and zero-torque point influence instantaneous efficiency. They also show that the force evolution can be described using the maximum values of drag and lift coefficients. These depend on the unsteadiness, characterized by a parameter equal to the difference between the velocities of the two blade edges divided by the normal component of the velocity of the blade centre. This parameter, fully related to the advance number, can be considered as a reduced frequency.