Abstract: A data providing device associated with a trajectory sensing system has at least a frame. The frame supports at least two sensing receivers and at least one emitter for the sensing receivers. The sensors sense movement and/or position with respect to a surface. The frame supports a third sensor that senses information (e.g., image data) from the surface at least in addition to movement. There is also a communication link from the two sensing receivers to a data storage device; a communication link from the third sensor to a data storage device or to a processor and then a data storage device; and a processor that determines position of the system with respect to the surface based at least in part on data from the two sensing receivers.