CX3D – On orbit 3D modeling of satellites
Figure 1 (left): Mock-up of an “uncooperating” satellite in the COMEX’ Pools. (right) Underwater acquisition of the 3D model in neutral buoyancy conditions (COMEX Pool). The 3D vision system is carried by a diver -instead of a satellite- for instance.)
Space debris are of growing concern to the global space community. One way to reduce the increase in the number of space debris added each year is by prolonging the on-orbit lifetime of the satellites either by performing on-orbit refueling or with the help of a service satellite. Most of the current solutions depend on information regarding the status of the target satellite or the debris. The target satellite could have been changed due to the effects of space weather, mechanical abrasion, malfunction and damage (especially in case of debris removal). Getting precise data on the actual state of the debris is therefore a primordial element in any mitigation strategy.
Especially in geostationary orbit, given the communication delay, a geostationary docking requires a sophisticated control system to dock with the target satellite autonomously without real-time ground assistance.
A solution for such application might come from the depths of the oceans: COMEX develops sophisticated underwater vision and photogrammetry systems that could be used in the space sector. ORUS3D by COMEX SA is the only underwater 3D photogrammetry solution certified for subsea metrology by Bureau Veritas that can create 3D models of underwater infrastructure with submillimetric resolution. The system can be used in various applications, ranging from precise cartography of archeological sites on the seabed, caves or autonomous classification of objects by underwater robots (ROV or AUV).
The system is proposed to produce high resolution and precision models of a satellite in orbit with the help of computer vision and photogrammetry . From a set of images that are seeing the same scene with various angles, CX3d will compute a model that is made of the scene interest points 3D coordinates and the position of the image.
The system has been tested for the space sector in different set-ups at the COMEX facilities in Marseille, France: COMEX performed underwater trials with a mock-up satellite to verify if neutral-buoyancy simulations of such a system could be feasible (e.g. simulating manipulations of a target satellite by a service satellite underwater in simulated weightlessness).
Also tests in dry conditions were performed with the system to verify if it could be implemented on existing space simulators.
Figure 2: (left): A satellite mock-up at COMEX workshop. (Right): 3D model of the mockup satellite generated by CX3D. Figure 3: Red arrow points CX3D system ability to detect and measure the damage areas in the satellite (in this case small impact holes in millimeter size)