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Considering the increased importance of telework systems in economies affected by COVID-19, telexistence technologies for remote guidance and navigation in general human activities are widely expec...

Performing general human behavior by experts’ navigation is expected to be realized as wearable technologies and computing systems are further developed. We have proposed and developed the prototype of the advanced behavior navigation system (BNS) using augmented reality technology. Utilizing the BNS, an expert can guide a non-expert to perform a variety of tasks. The BNSs are useful in tasks to be performed in harsh and hazardous environments, such as factories, construction sites, and areas affected by natural disasters (e.g. earthquakes and tsunamis). In this paper, we present a BNS that is specifically designed to operate in harsh environments, with characteristics such as wet or dusty conditions. The implementation, experimental results, and evaluation of the BNS prototypes are presented.

With advances in wearable computing, wearable virtual reality and wearable robotics have become popular areas of research. This work focuses on task execution where traveling motion of a worker is required and the traveling instructions are provided to the worker by an instructor. The goal of this research is to develop the behavior navigation system that can provide work and traveling instructions through showing the instructions visually and intuitively. The worker is a person who executes a task at a work site according to visually presented instruction by the instructor. A graphical human model of the instructor which moves in the same manner as the instructor is presented to the worker to provide the work instruction. A traveling instruction is defined by the relative position and orientation based on the current position and orientation of the worker, graphically. The omnidirectional traveling instruction is realized by this relative traveling instruction. The effectiveness of the developed system has been verified by a number of experiments.

A robot is an important tool for collecting data such as camera images at a remote site. These camera images are also used for robot operation. In this paper our aim is to develop an information collection system that can collect environmental information efficiently and can reduce the operational load for controlling a robot by realizing reduction of a travelling distance without reducing amount of collected information. An omnidirectional camera unit is used to capture an omnidirectional image around a robot at a time. When we need to access information around the place where the robot has already passed by at least once, the robot does not need to return to the place to get the information but it can be collected from stored omnidirectional images by choosing the point of gaze and gaze direction that indicate the place where an operator wants to look at. The conducted experiments show effectiveness of the developed system.

PurposeThe purpose of this paper is to describe a standing style transfer system, ABLE, designed to enable a person with disabled lower limbs to do daily‐life activities without special infrastructure. Actually, ABLE is mainly intended for use by people who have spinal cord injuries and who cannot move hip joints and lower extremities: the level of spinal cord injury is L1.Design/methodology/approachABLE comprises three modules: a powered lower extremity orthosis, a pair of telescopic crutches, and a pair of mobile platforms. When traveling in a standing position, the user wears the powered lower extremity orthosis to fix his posture, and rides on the mobile platforms. The user uses crutches to keep his body stable. These telescopic crutches also play an important role of power assistance in standing‐up and sitting‐down motions, or going up/down a step. The user can enter narrow spaces, although stability is emphasized in wide spaces because it is possible to alter the contact points of the crutches freely.FindingsMotions are discussed in a standing position: traveling and rotating, and the chair and step motions. Experimental results related to these motions confirm the design's effectiveness. The authors improve previously developed mobile platforms for better operationality and stability. An ultrasonic motor was used for steering the mobile platform instead of the prior DC motor. The benefits of the ultrasonic motor enable the new platform to reduce its backlash in steering. A supporting plate and an active ankle joint attached to each mobile platform contribute stability when traveling in the standing position. The authors show the experimental results using new mobile platforms.Originality/valueThe paper demonstrates novelty and originality of ABLE in its composition, which enables a person with disabled lower limbs to travel in a standing position on a pair of small mobile platforms. This system is regarded as a biped‐type leg‐wheeled robot system that has high energy efficiency and good mobility for steps because of its wheels and legs; moreover, it has a pair of crutches for stability.

A standing style transfer system, ABLE, is designed to assist a person with disabled lower limbs to travel in a standing position, to stand up from and sit down in a chair, and to go up and down steps. The ABLE system comprises three modules: a pair of telescopic Lofstrand crutches, a powered lower extremity orthosis, and a pair of mobile platforms. In this paper, the telescopic Lofstrand crutch is mainly discussed. This crutch has no actuator, and its length is switched between two levels; it assists the person when standing up and sitting down in the short length state, while it maintains the body stability in a standing position when traveling in the long length state. The experimental results related to the traveling in the standing position and standing up motion confirm the design's effectiveness.

Rescue robots have proved to be an extremely useful work partner for urban search and rescue (USAR) missions. Human rescuers who carry out these missions frequently enter dangerous zones to search for survivors; however, due to the unstable nature of collapsed buildings or objects, their lives may also be threatened. For this reason, in order to reduce life-threatening risks, rescue robots are deployed to carry out the job instead. Rescuers can now operate the robots at a safe place while the missions are carried out. When the robots have gathered enough information about the location of the victims and data about their physical conditions, rescuers can then enter the disaster site with enough knowledge to avoid harm and rescue the victims in the shortest time possible. In this paper, we introduce examples of 'effective multiple robot cooperative activities' and 'a study of the number of robots and operators in a multi-robot team' from our experiences gained from participating in RoboCup Rescue competitions.

Motion planning for coupled rigid bodies in a horizontal plane is investigated. The rigid bodies are serially connected by passive revolute joints. The dynamic constraints on the system are second-order nonholonomic constraints. We attempted to control those n coupled rigid bodies by the translational acceleration inputs at the first joint. If each rigid body is hinged at the center of percussion, it is possible to compose a positioning trajectory by connecting rotational and translational trajectory segments. Each rigid body can be rotated about its center of percussion one after another. When all of the rigid bodies are aligned on a straight line, they can be translated. The algorithm for positioning is presented. Simulations show that the coupled planar rigid bodies can reach the desired configuration by the constructed inputs.

Cooperative transportation of an object by two or more mobile robots requires each robot to exert an appropriate force to support and move the object, to move along the object, and to maintain the robot's attitude stably. Studies of cooperative transportation by multiple robots so far have scarcely considered the stability of the robot's attitude influenced by the force from the object. To take part in cooperative transportation, a mechanically unstable robot, such as a wheeled inverted pendulum, needs to control the force and follow the object while standing stably against the force in an integrated manner. We call this "cooperative behavior". To realize this behavior of a mechanically unstable robot, we built a control system to estimate the external force, maintain standing, and exert a specified force. Experiments were conducted on cooperative transportation between a human and the robot.

Control of a manipulator with a passive joint which has neither an actuator nor a holding brake is investigated. The manipulator has three degrees of freedom in a horizontal plane, with the third joint being passive. The dynamic constraint on the free link is shown to be second-order nonholonomic. Controllability of the system is proved by constructing examples of the input trajectories from arbitrary initial states to arbitrary desired states, considering the motion of the center of percussion of the link. Trajectories for positioning are composed of simple translational and rotational trajectory segments. The trajectory segments are stabilized by nonlinear feedback control. Simulations and experimental results show the effectiveness of the planned trajectory and the feedback control law.

Feedback control of a manipulator with a passive joint which has neither an actuator nor a holding brake is in-vestigated. The manipulator has three axes in a horizontal plane, with the third joint being passive. The dynamic constraint on the free link is 2nd-order nonholonomic. A trajectory for positioning is composed of simple transla-tional and rotational trajectory segments. The trajectory segments are stabilized by nonlinear feedback, considering the motion of the center of percussion of the free link. Simulations and experimental results show the effectiveness of the feedback control law.

Head Mounted Displays (HMDs) are the most popular devices for virtual reality, telexistence/telepresence humanoid operation, and remote behavior navigation. Telexistence/telepresence robot operation is an advanced teleoperation, enabling a human operator to perform remote dexterous manipulation tasks while having the feeling of being present in the remote environment. Behavior navigation is a novel technology that allows an expert to navigate a remote unskilled cooperator to perform general tasks. Since it is difficult to realize a large field of view (FOV) with an HMD, this has led to the development of immersive surround display systems. However, the fact that the operator's arms sometimes conceal the screen image of the surround display presents a serious drawback. To improve the performance of robot operation or remote behavior navigation in unknown environments, we propose the simultaneous utilization of a slimline HMD for central vision and a surround display for peripheral vision. Users of this novel display system can see the relatively high-resolution image on the display screens of the HMD, and their arms do not conceal the HMD image. In addition, users can see the large FOV image on the surround display around the HMD, although this may still be concealed by the user's arms. This enables full utilization of the natural and large FOV image. In this paper, we present the concept of a hybrid head mounted/surround display system, describe the configuration of a prototype setup, and present the results of a preliminary experiment.