Abstract
The so-called Tethered Space Robot (TSR) is a novel active space debris removal system. To solve its problem of non-cooperative target recognition during short-distance rendezvous events, this paper presents a framework for a real-time visual servoing system using non-calibrated monocular-CMOS (Complementary Metal Oxide Semiconductor). When a small template is used for matching with a large scene, it always leads to mismatches, so a novel template matching algorithm to solve the problem is presented. Firstly, the novel matching algorithm uses a hollow annulus structure according to a FAST (Features from Accelerated Segment) algorithm and makes the method be rotation-invariant. Furthermore, the accumulative deviation can be decreased by the hollow structure. The matching function is composed of grey and gradient differences between template and object image, which help it reduce the effects of illumination and noises. Then, a dynamic template update strategy is designed to avoid tracking failures brought about by wrong matching or occlusion. Finally, the system synthesizes the least square integrated predictor, realizing tracking online in complex circumstances. The results of ground experiments show that the proposed algorithm can decrease the need for sophisticated computation and improves matching accuracy.
Highlights
MotivationOn-orbit service technologies are drawing more and more attention, since they have many potential values for novel applications, such as space debris cleaning, on-orbit assembly, and maintenance, as shown in [1,2,3,4]
We present a novel dynamic template matching that may be used for a Tethered Space Robot (TSR)’s monocular visual servoing scheme
A large volume of experimental results of virtual, actual and robotic tests show that our proposed matching method can quickly detect assigned small template regions with excellent accuracy under various environmental conditions
Summary
On-orbit service technologies are drawing more and more attention, since they have many potential values for novel applications, such as space debris cleaning, on-orbit assembly, and maintenance, as shown in [1,2,3,4]. For on-orbit service tasks, they are usually modelled as a manipulator mounted on a rigid body structure. Limited by the manipulator length their flexibility seems to not be enough for some novel emerging space tasks [5,6]. Aiming to overcome these rigid manipulator arms’ shortcomings, our proposed Tethered Space Robot (TSR) system is designed to be different from traditional robotics for space manipulation, as shown in [7]. As a novel type of space robot, it has a creative architecture, whereby the TSR comprises. For our target, which has a monotonous texture and simple structure, this becomes even more troublesome
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
