Vibrotactile feedback has long been used to improve the human motor learning process through information transfer. However, in most of the approaches described in the literature, only the joint angles of the limb are guided. To guide motions that involve multiple degrees of freedom (DOFs), the user needs to interpret multiple simultaneous vibrotactile cues (at least one cue per joint), which is difficult. In this letter, we guide the position of a user's wrist in space by producing a vibrotactile cue at any place around the wrist by using a vibrotactile illusion known as “Phantom Sensation” (PS). In a user study that involved 10 male participants, the vibrotactile cues produced by PS were reasonably accurately located with an average error of $\boldsymbol{7.9^\circ }$. To maintain consistency between the vibrotactile cue location and the global frame, we measured the user's wrist rotation and adjusted the position of the vibrotactile cue accordingly. When rotating their hand, the participants recognized the location of the vibrotactile cue with an average error of $\boldsymbol{9.3^\circ }$ . By using the proposed feedback paradigm, we guided users’ wrists in space under two conceptual mappings (“push” and “pull”). This experiment examined the participants’ motion path efficiency (ME), which measures the directness with which the user's wrist moves toward the desired position. The participants reached the desired positions under the vibrotactile feedback alone. The average MEs of the “push” and “pull” mappings were 44.3% and 52.4%, respectively. We will apply the proposed method under the “pull” mapping to guide real life tasks, such as book classification or rehabilitation.

In recent years, multiple navigation systems using vibrotactile feedback have been studied, due to their ability to convey information while keeping free the visual and auditory channels, besides eliciting rapid responses from users. In the current stage, most navigation systems with vibrotactile feedback in the literature focus on guiding users around space using a fixed number of vibrotactile cues, which are limited by the number of vibrators. In this paper, we present an approach to guide people around space using multidirectional vibrotactile feedback (MVF). The MVF can produce vibratory cues on the user's left lower leg with an average directional resolution of 15.35 for cases when the user is not moving, using only six vibration motors, by exploiting a vibrotactile illusion called Phantom Tactile Sensation (PTS). In a preliminary test of dynamic direction recognition experiment, users reported they tend to become less sensitive to vibration under long-time continuous vibration. As a result, besides offering users a continuous vibration to indicate directions, we also considered producing the cues during either the swing or stance phase to users in this experiment. The result of a direction recognition experiment while walking shows that the average recognition error for the cues when produced in the swing or stance phases are lower than the recognition error when the cues are continuously produced. We carried out a navigation experiment to test the feasibility of using the proposed direction display to guide people around an open area in real-time. In this experiment, users were able to reach the goal within the time limit guided only by the proposed feedback around 90% of the times for both gait phases.

Demographic changes in our society are putting a heavy burden on care facilities and health-care infrastructure. While the elderly population is steadily increasing, there is an acute shortage of caregiving experts and professionals. This problem is becoming more severe in superaging societies, namely, Japan. Hence, this urges new and practical solutions for welfare facilities to mitigate the burden on caregivers and human supporting partners by introducing robotics assistance through information and communication technology (ICT). In this work, we present a new multirobot cooperation and coordination framework at different intellectual computation levels for care facilities. The framework is developed to bring the health-care 4.0 concept one step closer to reality, under the ongoing project “Moonshot Research & Development,” in Japan. First, we present an Internet of Things (IoT) integration system that is designed to include different passive and active assistive robots. Then, we redesign robot systems and develop a semiautonomous platform that can perform tasks based on user/patient interaction in real-world care facility scenarios. Our framework provides human–robot interaction under shared autonomy between the user and assisting robots to improve the efficacy of the users in everyday tasks. Tohoku University’s new state-of-the-art Living Lab facility is used to prepare a real-world scenario, where we present our experimental results. We also discuss the open problems in future care and human assistance aspects.

In recent years, automation has significantly advanced the automobile manufacturing industry. However, many tasks still involve human intervention, so there is a demand for the development of robots to support workers. Additionally, as the human-centric approach, such as Industry 5.0, is gaining attention, it is expected that support robots like these will become necessary in the future. This study aims to develop a system that can support workers by utilizing robots that anyone can easily use and flexibly respond to various tasks. This system adopts a large language model (LLM) for work planning and generates tasks that robots can execute by making bidirectional and interactive suggestions and modifications through natural language dialogue in response to human demands, aiming to improve further productivity and the working environment in automobile manufacturing factories. The proposed system was tested in a simulated factory environment and then the performance was confirmed in an actual factory setting. And it was confirmed that various tasks can be executed by robot through work planning and dialogue with the LLM.

Robotic systems play a very important role in exploration, allowing us to reach places that would otherwise be unsafe or unreachable to humans, such as volcanic areas, disaster sites or unknown areas in other planets. As the area to be explored increases, so does the time it takes for robots to explore it. One approach to reduce the required time is using multiple autonomous robots to perform distributed exploration. However, this significantly increases the associated cost and the complexity of the exploration process. To address these issues, in the past we proposed a leader-follower architecture where multiple two-wheeled passive robots capable of steering are pulled by a leader robot. By controlling their relative angle with respect to the leader, the followers could move in arbitrary formations. The proposed follower robots used rubber tires, which allowed it to perform well in rigid ground, but poorly in soft soil. One alternative is to use lugged wheels, which increase the traction in soft soils. In this paper we propose a robot with shape-shifting wheels that allow it to steer in both rigid and soft soils. The wheels use a cam mechanism to push out and retract lugs stored on its inside. The shape of the wheel can be manipulated by controlling the driving torque exerted on the cam mechanism. Through experiments we verified that the developed mechanism allowed the follower robots to control their relative angle with respect to the leader in both rigid and soft soils.