Ceiling mobile robots are anticipated for trans-porting component parts in production sites. In our previous study, we had developed a crawler-type ceiling mobile robot named "HanGrawler." In this study, we aim to realize 1 m/s and 90°/s speed movement on par with existing ground carriers, and reveal the factors contributing to the improvement in speed and stabilization. Accordingly, we develop HanGrawler 2, which inherits the basic approach of HanGrawler. In HanGrawler 2, the mechanism for hanging from the ceiling moves faster, and the driving power of the linear and rotational movements is improved drastically. Newly installed sensors detect the hanging mechanism and robot body position relative to the ceiling plate. By calculating the insertion timing based on the position of the hanging mechanism, the certainty of insertion is improved. Support rollers pressed against the ceiling stabilize the traveling posture of HanGrawler 2. Performance evaluation experiments confirm that HanGrawler 2 can travel linearly at a speed of 1 m/s with a 40 kg load and turn at a rotational speed of 90°/s. Based on the experimental results, it is confirmed that the design solutions for HanGrawler 2 are effective in realizing reliable ceiling mobility and that the high-responsiveness inherited from the original HanGrawler mechanism contributes to the realization of high-speed movement.

In this article, we present a ceiling-mounted mobile robot, HanGrawler, with high-speed mobility and the ability to freely select and adjust its route under a ceiling plate. HanGrawler hangs from the holes of a perforated metal ceiling plate using newly developed mechanically constrained hanging mechanisms mounted on crawler-type traveling equipment. These mechanisms continuously grasp the ceiling holes while moving in a straight line. Specially designed turntables are installed at certain ceiling points to change the HanGrawler movement direction to facilitate two-dimensional motion. A performance evaluation experiment confirms that HanGrawler can travel linearly at 0.1 m/s, turn at an 8.5°/s rotational speed, and carry a maximum load of 60 kg. The experiment also reveals that HanGrawler can carry a heavy load only when the timings of the hanging mechanism hooking motions and turntable rotational speed are tuned. This transport system can be utilized not only for part transportation on production lines but also for logistics in general.