An outline of the Advanced Robotic Technology Research Center, Kindai University Fundamental Technology for Next Generation Research Institute is given. The research activities of the Advanced Robotic Technology Research Center are classified into the following five fields, field robotics, medical and welfare robot, dynamics controlled robot, soft-robotics, and parallel link robot.

The study aims to develop automatic transplanting equipment for chain pot seedlings. We intend to practice the shaft tillage cultivation using an autonomous farming robot. We had developed an autonomous working vehicle and automatic transplanting equipment for plug seedlings used in shaft tillage cultivation. To reinforce the robot system’s versatility, we developed transplanting equipment for the chain pot seedlings. We experimentally investigated the transplanting performance. Approximately 84% of the seedlings were automatically transplanted using the developed equipment. Since the equipment was performed well in the failure samples, we assumed that the cause of such failures was attributed to seedling quality. In addition, we measured the power consumption of the equipment used to build an electrical power supply system. Consequently, we calculated the power requirements for each process. Compared with the plug seedling equipment developed in the previous study, the chain pot seedlings’ power requirement was lower because the conveying actions of seedlings were different. In the next stage of our research, to construct a fully automatic system, we will consider the seedling raising method in which seedlings can become uniformly high-quality and investigate the plant establishment performance using the developed equipment.

In recent years, different types of commercial rollators or gait-training devices have been widely used by elderly people, suffering from dementia, for their daily activities to avoid being bedridden. However, the effectiveness of most of these commercial devices has not been investigated thoroughly. In this study, a novel rollator with a freely rotating chest pad, integrated with two angular sensors and two load cells, was developed. Walk measurements were carried out on four young healthy subjects who performed walk tests using the developed rollator. To measure the motion of the lower limbs, two goniometers were attached to the exteriors of both the knees, and two more were attached to the exteriors of both the ankle joints of the subjects. The results of the pressing forces on the pad measured by the load cells, pad rotations, knee extensions, and ankle rotations were demonstrated. Frequency analyses were performed and correlation coefficients were computed for the obtained results. The relationship between the pad rotation and the motion of the lower limbs was investigated, and the effectiveness of the developed novel rollator in walk assistance was discussed.

In this study, an active exercise function was added to a continuous passive motion device, which is widely used in rehabilitation therapy for function enhancement. The objective is to reduce physical overwork on the part of physical therapists and promote self-rehabilitation in patients. Impedance control based on position control was applied to provide active exercise load. Various active exercise loads are required to reproduce daily life muscle activity. Accordingly, a friction load model was introduced in the impedance control system. The effects of increasing the types of active exercise loads were evaluated by analysis of muscle activity during experimental tests, and a new muscle activity that could not be attained by the conventional spring-mass-damper load model was confirmed.

This paper describes a fish-like robot with a deformable outer shell fabricated using a silicone mold. Based on the difference in the contact condition between the serial-link robot and the shell, the fabrication methods are classified into embedded type and skin type. This study analyzes the mechanical properties of embedded and skin-type underwater robots from the viewpoint of material mechanics. A low-torque motor can sufficiently drive the skin-type underwater robot if the friction coefficient and pressure between the skin and the link are appropriately selected. Furthermore, the outer skin of the fish-like robot can be easily fabricated by defoaming in the chamber of a vacuum-packaging machine. Finally, the performance of the skin-type robot in air and underwater was assessed through several experiments.

This paper presents a miniature motorcycle robot developed for the purpose of research on attitude control at the time of traveling and resting a motorcycle mobile body. The miniaturization has been achieved by developing a small board using MPU and FPGA as a controller. This motorcycle mobile robot has a mechanism featuring the use of an inertial rotor in addition to the steering mechanism of a common motorcycle. The use of the inertial rotor enables the balance to be maintained even at the time of rest. Using this function of being able to maintain balance even at the time of resting, we measured the effect of a steering operation on balance and successfully compared it with the theory. Furthermore, balanced traveling is achieved by using only an inertial rotor at a low speed and only steering at high speed.

This paper presents a communication robot system with a simple LED display for representing timing for turn-taking in human-robot interaction. Human-like conversation with non-verbal information, such as gestures, facial expressions, tone of voice, and eye contact enables more natural communication. If the robots could use such verbal and non-verbal communication skills, it would establish a social relation between a robot and human. Timing and time interval for turn-taking in human communication are important non-verbal cues to efficiently convey messages and to share opinions with each other. In this study, we present some experimental results to discuss the effect of response timing for turn-taking in communication between a person and a robot.

Water depth is an important piece of information for the ship navigator when entering the port. However, the depth is not always accurate as indicated in the chart due to tides and sedimentation. This study aimed to develop an underwater robot to easily measure water depth. To measure the water depth at the place where the ship is moored at the quay, this paper proposed the method of measuring the water depth by submerging an underwater robot under the moored ship. Actual sea area experiments indicated the effectiveness of the underwater robot.

In this paper, we proposed a distributed controlled gait rehabilitation and locomotion support system through human-robot cooperative control, and combination of two cane-type walking support robots (left and right) and one wheelchair robot to support the walking and locomotion of a person in need of walking assistance. The proposed system can realize five types of motion support from gait training to daily motion support, using three types of motion support modes with a distributed robot control system comprising up to three robots to support the user’s independence for walking and moving. The cane-type walking support robot moved in response to the manipulation force applied to the robot by the user, and can realize walking/movement support in all directions through the omnidirectional traveling part. In addition, the height of the robot can be adjusted according to the user’s physique, and the motion characteristics can be set according to the user’s walking ability. The wheelchair robot has a seat that can be raised, lowered, and tilted to provide standing assistance for the user and mobility support as an electric wheelchair. In this study, we developed a prototype of the proposed system and demonstrated its feasibility for five types of assistive actions in experiments with healthy subjects.

We are currently facing a “labor crisis,” particularly in the field of logistics, because of reductions in the labor force. Therefore, industries must make their logistics more efficient by utilizing autonomous mobile robotics technologies. This paper proposes a hierarchized map concept that makes unmanned delivery tasks which use multiple autonomous robots more efficiently. Using our proposed concept, an autonomous mobile robot can move automatically on a more efficient path than using current methods. In addition, the management platform for autonomous robots can be used to prevent accidents such as collisions or deadlocks between autonomous robots.

The aim of this study was to propose a tread swing mechanism for lower-limb strength training devices and to confirm its effects. In the standing position and for training the lower limbs, if the tread-surface angle is inappropriate, the posture of the knee joints gets affected, and knee adduction/valgus moments, which result in knee stress, get generated. The target training exercises are the front-back leg scissors and open-close leg triangle exercises. With regard to the swing of the tread, it is necessary to realize a pitch/yaw rotation and a roll/yaw rotation for the former and the latter exercises, respectively. As a result, knee joint stress can be reduced by moving the center of pressure (COP). The proposed mechanism has a further differential mechanism that utilizes the difference between the pulley diameters. The translational movement force of the tread is transmitted as the torque of the swing motion for the pitch, roll, and yaw through the effects of a differential mechanism. The rate of the swing angle can be changed by adjusting the pulley diameter. As a result of evaluating the effect of exercises using a manufactured device, it was confirmed that the tread performed a predetermined swing motion. It was also confirmed that the COP position changed. Therefore, it is expected that knee joint stress will reduce. Rehabilitation and strength training that result in small knee joint stresses and generate large muscle load are in great demand for people experiencing knee joint failure.

For autonomous navigation, localization in an environment is a fundamental capability. In this regard, it is necessary for robots to have environmental maps. The environmental maps are, in general, built beforehand through SLAM. On the other hand, the authors have focused on cadastral data including road and building information. In this paper, we propose a localization method using an environmental map based on the cadastral data. The robot is assumed to be equipped with 3D LiDAR. However, the cadastral data does not include natural objects, such as trees. Moreover, the position of a building in the cadastral data is sometimes different from its actual position in the environment. For data association between the sensor measurements and environmental map, we describe point cloud processing. Furthermore, we use an RGB-D camera to obtain a dense point cloud. In the navigation experiments, we show that the robot is able to move towards the destination autonomously through the localization in the map.

Over the last few years, numerous robotic ankle-foot orthoses have been developed to help stroke patients optimize gait rehabilitation. In this paper, we present a study on the effects of assistance on dorsiflexion-restricted gait. Our high-dorsiflexion assistive system aims to provide full assistance to realize passive training of dorsiflexion during the swing phase and prevent compensatory movements. This system, which includes a McKibben-type artificial muscle and an air source, is lightweight and provides a high-dorsiflexion torque. The device could help boost overground gait rehabilitation in stroke patients. With this system, we conducted an experiment on five healthy participants whose dorsiflexion movements were restricted, and the extent of their compensatory movements differed. The results of the processed surface electromyography data differed significantly when dorsiflexion movement was assisted by our system. The spatial parameters also showed significantly improved compensatory movement inclination with sufficient assistance. These results indicate the potential of our system to assist in passive training of ankle dorsiflexion movements and to prevent incorrect gait in patients with low dorsiflexion abilities.

A two-wheeled vehicle using bimetal sheets that travels on a hot horizontal surface by using only thermal energy is proposed herein. Each wheel is wrapped with a bimetal sheet, and the deformation of the sheet causes the wheel to roll. The rolling motion is investigated based on a simple physical model to provide insights into the rolling principle and its characteristics. Subsequently, by comparing several different wheel structures, the optimal wheel structure for the vehicle is selected. The performance of the developed vehicle is tested on a hot plate whose surface temperature is 100°C higher than the ambient air temperature. It is discovered experimentally that the vehicle can travel at a speed of approximately 60 mm/s when no load is applied. The vehicle can travel by supporting a load of approximately 400 g, which is almost double its weight.

The pointing operation using a mouse is widely implemented as a method for an operator to intuitively operate a pointer on a display. However, the dynamic characteristics of the pointing operation and pointer movement, such as inertia and viscosity, cannot be adjusted using ordinary pointing devices. As an alternative to a mouse pointing system, in this study, we propose a novel haptic pointing system in which the dynamic characteristics of the pointing operation and pointer movement can be adjusted using a robot manipulator under mechanical variable admittance control. The dynamic characteristics of the robot motion and pointer movement are varied sequentially during the pointing operation by varying the inertial and viscosity parameters of the proposed admittance control strategy using a mechanical device attached to the robot manipulator. The experiment was conducted to reveal the effectiveness of adjusting the pointer movement dynamics by modifying the pointer movement control loop and the ratio of the operating force with respect to the amount of pointer movement. The experimental results demonstrated that the performance of the pointing operation was improved by appropriately adjusting the pointer movement dynamics.

We describe here our design and implementation of a cyborg insect, called CameraRoach, with onboard camera feedback that can be navigated via remote control providing a first-person view. The camera pack is mounted on the Madagascar hissing cockroach, which is small enough to fit into crevices but also can carry a printed circuit boards with power, communication, and sensor components (visual camera). For navigating the cockroach, we implemented a unique electronic backpack neural stimulator, which allows the cockroach to be maneuvered on a desired path with a joystick. A high-resolution wireless camera, also included in the backpack, sends live images via a WiFi (Wireless Fidelity) network. We present the results of an evaluation experiment with the CameraRoach and compare it with the other state of the art systems like the Beetle-Cam.

In this study, the authors conduct an operational test of a small weeding robot in paddy fields, and classify its behavioral incapacitations into two groups. Furthermore, the authors propose a leg structure for overcoming a sudden increase in water depth, one of the main causes of incapacitation. The robot is a two-wheeled vehicle with balance floats in the front and rear of the body, and the proposed structure enables the wheels to reach the ground by deforming the legs holding the wheels (variable-leg). The variable-leg robot is compared with a fixed-leg robot via a water tank experiment. It is verified that the variable-leg model can run at water depths of up to 180 mm, whereas the fixed-leg model can only run at water depths of approximately 80 mm. Furthermore, the variable-leg robot can adapt to dynamically changing water depths, as demonstrated by running over a hole.

Wheelchair users require the assistance of station staff when boarding trains due to step differences and the gap between the platform and train. Therefore, they feel stressed in the movement with the train. In addition, the burden on station employees is increasing with the increasing number of wheelchair users at railway stations. In this study, an assistance device is proposed to address these challenges. This device can be used with any existing wheelchair, platform, and train and does not require external power sources, such as electricity. Using this device, a wheelchair user can board a train independently without assistance.