Abstract: A method and apparatus for tracking movement of an object in three-dimensional (3D) space uses a using a single sensor to capture images of the object moving through the 3D space. A change in change in position of the object in the 3D space is determined based on a change in size of the object in the images. The change in position is used to construct a trajectory of the object and the trajectory represents the movement of the object through the 3D space. Trajectories of a plurality of objects may be determined. The objects may be naturally occurring, or they may be manufactured and introduced into the 3D space. The determined trajectories may be used to characterize a flow field in the 3D space and produce an output comprising a 3D representation of the flow field.

Abstract: Apparatus and methods for measuring force exerted by an object moving in a fluid or force of a moving fluid on a stationary object. Embodiments may be configured to measure power exerted by an object moving in a fluid. At least one sensor disposed on the object outputs at least one sensor signal corresponding to a pressure differential between first and second surfaces of the object. Data derived from one or more sensor signals may be processed according to a model to output a measure of the force and/or power of the object moving in the fluid or the force of the moving fluid on the stationary object, as a function of time. Embodiments may be configured for applications such as providing feedback for control of actuators in electromechanical systems for liquid or gaseous media, and providing performance metrics during water sports, such as swimming and paddling.

Abstract: Apparatus and methods for measuring force exerted by an object moving in a fluid or force of a moving fluid on a stationary object. Embodiments may be configured to measure power exerted by an object moving in a fluid. At least one sensor disposed on the object outputs at least one sensor signal corresponding to a pressure differential between first and second surfaces of the object. Data derived from one or more sensor signals may be processed according to a model to output a measure of the force and/or power of the object moving in the fluid or the force of the moving fluid on the stationary object, as a function of time. Embodiments may be configured for applications such as providing feedback for control of actuators in electromechanical systems for liquid or gaseous media, and providing performance metrics during water sports, such as swimming and paddling.