Ryota Hayashi

Myriapod robot i-CentiPot via passive dynamics — Emergence of various locomotions for foot movement

The purpose of the research is to develop a myriapod robot i-CentiPot ??? that achieves significant mobility against unpredictable environment via passive dynamics. In the paper, we change foot phase, and observe locomotion. We also consider about the analogy between i-CentiPot ??? and some myriapoda.

Development of Flexible Mono-Tread Mobile Track Using Rotational Joints

Robot technology is expected to become applicable to missions on rough terrain, such as search and rescue activities, planetary exploration, and environmental investigations. The robots in such environments need high mobility against extremely rough terrain. Tracked vehicles are effective against rough terrain because the contact pressure of the vehicle can be distributed more widely. However, it is difficult for a typical tracked vehicle composed of a pair of tracks to significantly change its length/width ratio from 1:1 because of its turning property. To improve mobility, serpentine tracked robots are designed to move on rough terrain. We proposed a flexible mono-tread mobile track (FMT). An FMT is a mono-track system, and its body has a vertebral structure composed of rigid segments (called vertebrae) connected by flexible segments (called intervertebral disks). An FMT can flex more widely in three dimensions, thereby turning and climbing over obstacles. This feature is an advantage over previous mono-track systems. Prototypes of FMTs called RT02-WORMY and RT03-LIPAN have been developed and validated the system’s mobility. The body of an FMT, except for both sidewalls, is completely surrounded by only a track belt. However, the prototypes have a problem with interference and derailing in the track belt that is caused by flexion and the surface profile of the ground. The objective of this study, therefore, is to develop a new prototype of an FMT called RT04-NAGA. NAGA adopts a combination of one-degree-of-freedom (DoF) rotational joints instead of flexible components and an accurately designed guide rail system to prevent the belt from interfering with operation or derailing. To validate the performance of the prototype, we conducted the fundamental tests of the prototype, such as energy consumption; mobility with a ditch, a vertical wall, a stairway and a spiral stairway; and the standard tests following the regulations of the National Institute of Standards and Technology (NIST).

Development of a small and lightweight myriapod robot using passive dynamics

Typical myriapod robots were originally large and heavy for actuating numerous joints. Therefore, it is difficult for these robots to synthesise aspects of intelligence, such as adaptability of Myriapoda. The aim of this study is to develop a light, simple, and adaptive myriapod robot by implementing passive dynamics. In the paper, we develop a prototype of the myriapod robot, the i-CentiPot P (implicit brain centipede robot prototype) based on passive dynamics to validate its fundamental mechanism. The i-CentiPot P is lightweight (weight of approximately 1.5 kg) and small (length, width, and height of 1.2 m, 20 cm, and 5 cm). The experimental results showed that the i-CentiPot P could climb over or avoid some obstacles autonomously. The i-CentiPot P did not have active torso joints. Nevertheless, we observed that torso undulation emerged. This result indicates that interaction between the legs, the flexible and passive torso, and the ground provides the spontaneous undulation.

Flexible mono-tread mobile track with shelled structure: Performance tests using fields of RoboCup

We previously proposed a shelled structure of flexible mono-tread mobile track (FMT), a dual camera system, and an attitude display. In the report, we conducted performance tests for the latest FMT prototype, RT05-COBRA, using fields of RoboCup Rescue Summer Camp at Aichi Institute of Technology.