As a sprint canoe athlete takes a stroke, the flow around their blade governs the transfer of power from the athlete to the water. Gaining a better understanding of this flow can lead to improved equipment design and athlete technique to increase the efficiency of their stroke. A method of modelling the complex motion of the sprint canoe stroke was developed that was able to simulate the transient 2-phase blade-water interactions during the stroke using computational fluid dynamics (CFD). The blade input motion was determined by extrapolating the changing blade position from video analysis of a national team athlete. To simulate the blade motion a rigid inner mesh translated and rotated according to the extrapolated blade path while an outer mesh deformed according to the translation of the inner mesh; allowing for independent motion of the blade throughout the xy-plane. Instabilities associated with the blade piercing a free surface were dealt with by using a piecewise solution. The developed model provided a first look into the complex hydrodynamics of the sprint canoe stroke. Examination of the resultant flow patterns showed the development and shedding of tip and side vortices and the resultant pressure on the blade. Late in the catch, there was an unrealistic drop in the net force on the blade which was attributed to the over-rotation of the blade causing the top two-thirds of the blade to accelerate the near surface water forward. The inclusion of an approximated shaft flexibility showed the ability to improve the net force to more realistic values. / Thesis / Master of Applied Science (MASc)

A fully instrumented on-water sprint canoe system was designed, built, and tested. The system consists of: one 6-axis load cell in the paddle shaft at the blade, one inertial measuring unit (IMU) on the paddle, one IMU on the boat, and one GPS unit on the canoe boat. These sensors communicated wirelessly to a laptop where the data was processed and displayed in real-time. The sensors were rigorously tested and well-measured in their satisfactory accuracy. The system can provide a full decomposition of the blade water force into propulsive (forward/aft), side, and vertical forces. Previous systems for canoe have been extremely simple and rudimentary. There has been more effort in the rowing and kayak systems but they still failed to capture a full force profile. On-water tests with national-level athletes examined a wide variety of sprint canoe strokes at different paces, power inputs, rates, and stroke lengths. The measurement system could clearly see the differences in force profiles between the stroke sets. A number of efficiency measures were developed using the available data. Instantaneous and integral in-stroke force ratios were developed based on the blade's propulsive force to total force proportion. Derived stroke averaged efficiencies also provided more information. These produced measurements of energy/impulse input to the boat's propulsion output. Differences in such efficiencies could be clearly seen in the various collected stroke sets. This system will be highly useful to high performance athletes and coaches for modifying athlete technique. It has potential for improving equipment design and matching athletes to optimal blade styles. More academically, it can assist biomechanical assessments of sprint canoe and numerical flow studies around blades. / Thesis / Master of Applied Science (MASc) / A measurement system for a sprint canoe paddle was created that can evaluate an athlete's stroke performance during race-like conditions. This system was tested using national-level athletes in a true on-water setting. By measuring the force and orientation of the athlete's strokes, the system was able to clearly distinguish the performance of various stroke techniques. Analysis of the force profiles and the derivation of stroke efficiencies provided additional performance indicators. This is the first system to achieve this amount of measurement detail of any rowing or paddling sport. This fully instrumented paddle system is ready to be used as a coaching tool to improve athlete performance. It can also be used as an academic tool for paddle blade study.