Faced with the soaring prices of the audiovisual sports market with the explosion of revenues generated by TV rights (approaching one billion euros for the French football championship), the retransmission of matches has become a key element for the various investors. To offer viewers the most spectacular images, the wired camera, thanks to its mobility and speed, allows total immersion in the actions, with the players. Through this study I was interested in the control and dynamic behavior of a wired camera.
First, I tried to model the behavior of the system through geometric and dynamic analysis in order to simulate a trajectory of the device. Next, I tried to verify the relationships established previously to a simplified version of a wired camera moving in a 2-dimensional plane and to assess the different factors influencing its trajectory.
The model studied throughout this study is made up of only 2 cables connected to 3 motors which are attached to the camera by 4 attachment points. The M1 and M2 motors only have an impact on the elongation of one of the two cables, while the M3 motor has a coupled behavior. Assume the point camera and the attachment points of each cable are the same. The cables are assumed to be inextensible and without mass. The geometric hypotheses formulated previously made it possible to find the link between the length of the cables and the position of the camera. By deriving and injecting these relations into the relations linking the speed of rotation of each motor to the elongation speeds, the relation sought between the vector H and X. We deduce from this the passage matrix linking the two vectors H and X, which depends on the position of the camera that we will be able to use for the equation of motion.
This study has therefore shown that even with multiple assumptions and imprecise material, it is possible to have satisfactory results. I was able to observe the different factors influencing the behavior of the wired camera and visualize the trade-off that must be found in order to ensure a rapid movement of a large enough mass in the largest possible workspace.