This paper investigates balance maintenance for the quadruped-wheeled robot MELEW-3 under three legs supporting scenarios. Strategies were explored for both static and dynamic postures to stabilize the center of mass (CoM) after one leg is being lifted or locked, including adjusting the height of CoM and the horizontal position of the remaining legs. The effect of the inertia force on the CoM was also analyzed in dynamic posture. Theoretical verification through position calculations supports these adjustments.

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This study explores the design methodology for planar linkage mechanisms through topology optimization of a two-layer elastic body model. The application of topology optimization to mechanisms is expected to enable the creation of energy-efficient and high-stiffness mechanical systems; however, the approach remains unexplored. In this study, a planar linkage mechanism is approximately modeled using two elastic body layers connected by springs, allowing for the simultaneous optimization of link structures and joint placements through topology optimization. To obtain an optimal structure that functions appropriately as a mechanism, an optimization problem considering the degrees of freedom of the mechanism is formulated. The effectiveness of the proposed method is validated through numerical examples.

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Weight reduction in robots contributes to lower energy consumption and enhances safety by reducing impact forces in the event of a collision. This study uses additive manufacturing to design and fabricate a lightweight robotic link through topology optimization. Specifically, a grayscale representation achieved by varying the infill density relaxes manufacturing constraints and enables a higher-performance structure. Beams with different levels of relaxed constraints were subjected to compression tests using a press machine, and their stiffness was evaluated. Simulations showed an approximate 31% improvement in strength, whereas experimental tests confirmed a decline of approximately 44%.

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We investigate an inverse optimal control problem in which both some inequality constraints and the weights of a linear combination of cost terms are unknown. To understand the locally optimal behavior of the observed trajectories under these unknown parameters, we employ the Karush-Kuhn-Tucker (KKT) conditions. However, enforcing KKT conditions for both constraints and objective weights simultaneously introduces bilinear couplings, making the problem difficult to solve directly. To enhance tractability, we approximate the unknown inequality constraints with a convex hull to relax bilinear form. Given approximate constraints, we minimize the L2 norm of the stationarity and complementary slackness correcting deviations stemming from the convex hull approximation, to recover objective function from locally-optimal demonstrations. We validate our approach on a 2-DOF robotic arm, explicitly testing its performance with noisy data. Numerical results show that our method reliably recovers both the constraint set and objective-weight parameters under noise perturbations and supports effective planning of new constraint-satisfying trajectories in robotic control applications.

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For factory automation, a new concept of a reconfigurable robot hand is proposed, which is suitable for handling an object with a complex shape such as aircraft engine parts. This hand has fingers which transform into two different shapes, one is cylindrical for inserting a narrow space in a partition in containers, which is designed to avoid collision between workpieces for quality control, and the other is L-shape for supporting the weight of the object to ensure that it cannot drop. In this report, the concept and design of the proposed hand mechanism is clarified.

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In a versatile robotic assembly system in manufacturing, robots need to handle various parts, including flexible parts such as round belts and cables. In this paper, we present a method for grasping a round belt and installing it onto a pulley using a versatile robotic hand with telescopic parallel stick fingers. Targeting the round belt installation of a belt drive unit designed for the World Robot Summit 2018, we experimentally validate the feasibility of achieving the desired tasks with the proposed method.

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The instability of surface electromyography (sEMG) signals leads to significant burdens on the use of traditional prosthetic hands. This research aims to achieve six common prosthetic grasping actions by using computer vision to recognize the key characteristics of the objects to be grasped. Prosthesis wearers only need to install two-channel sEMG sensors and perform five easily recognizable gestures as control commands to enable functions such as system judgment, revision of inappropriate grasping actions, and rapid recognition of grasping actions. Additionally, haptic feedback is added to the prosthetic hand fingers to adapt to grasping objects of different sizes and shapes. These methods demonstrate the potential to improve the stability and flexibility of prosthetic hand control, effectively reducing the difficulty of using prosthetic hands to grasp various daily necessities.

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This research develops a center of gravity (COG)-based estimation algorithm to determine the grasping position of Japanese bento without requiring additional sensors or prior grasping trials, thereby enhancing automated production efficiency in the food industry. A large vision model (LVM) and YOLO11 are employed for initial bento detection and dish classification, followed by COG estimation using color thresholding and weight averaging based on pixel areas and dish density. Experimental validation using an actual manipulator UR3 demonstrates its effectiveness in accurately grasping. These results emphasize the importance of COG in object grasping and provide valuable insights into food production automation.

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This paper presents a novel helical locomotion-based soft crawling robot for in-pipe inspection. In robotics, helical locomotion is a mechanism that enables a crawling robot to move forward. This is particularly evident for wave-like robots that exploit the actuation of one or more helical shafts to generate a propulsive wave. This mechanism may potentially be suitable for pipeline inspection because it features a compact design along the pipe’s transverse section, and it can adapt to the structural variations of the pipes thanks to the flexibility achievable by modifying the shaft geometry. However, the pipeline environment is inherently affected by some factors, such as oil, sediment, and rust, that can compromise the robot's locomotion, and the robot itself may contaminate the external environment. The core idea of the paper is to enable the robot to perform its inspection operations while remaining isolated from the surrounding environment through a compliant tube that encloses it.

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This paper presents the laboratory validation of the ASSIST-FEEv3, a cable-driven elbow-assisting device that is designed to facilitate flexion and extension assisted movements. The proposed device is a lightweight and portable solution, ensuring user accessibility in both home and clinical settings. The validation process includes operational performance through controlled exercise tests according to a properly designed protocol. The evaluation involves a series of motion trials, during which data acquisition and real-time monitoring give the characterization of the device effectiveness. This assisting device has the potential to expand exercise opportunities beyond clinical settings, even into domestic environments for elderly people.

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This paper addresses the methodology of thermal monitoring through the use of thermal camera. This process makes several preliminary experimental tests with the thermal camera with the qualitatively proposed object, where the distance between the sensor and the object is suitable for the sensor's capture ability of the object temperature. The purpose of this procedure is to use the new technology for specific applications in cultural heritage sites by DIMEG Heritage Drone. This paper has been organized in several sections. In the first section, we present the DIMEG Heritage drone and present the procedure of thermal monitoring for inspection in built heritage site. And in the second section, we describe the thermal inspection and internal functionality of the thermal sensor. Finally, we conduct several experiments by using the thermal camera to detect thermal images (water seepage and corrasion) of the object. This experiment is considered a preliminary test in our work to prepare the next stage of our work, which is to integrate the thermal camera with a drone and run thermal monitoring mode for inspection in the heritage site.

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Telemanipulators are devices that consist of two main components: a control part (master) and an execution part (slave). They are widely used in various fields where remote control is necessary to manipulate objects or tools within a specific work area. The efficiency of a telemanipulator is often assessed by its degrees of freedom. In this study, starting from a telemanipulator featuring 3 degrees of freedom of pure spherical motion (previously presented by the authors), we propose three different mechanisms—both parallel and serial, spatial and planar—that, when appropriately combined with the spherical telemanipulator, can significantly expand the overall system's workspace. This expansion enhances efficiency and comfort for the operator. Finally, we compare the various systems based on their mechanical characteristics.

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This work proposes a new haptic mouse concept utilizing a pseudo-force effect. The haptic mouse proposed in this work elicits virtual force sensations by pressurizing the palm using an internal stimulator embedded in the mouse. Although no external force acts on the mouse, the user supposedly feels a virtual external force through the pressurization, which is provided in synchronization with the user’s operation on the computer. This paper reports on a prototype mouse with a one-degree-of-freedom stimulator. The stimulator is driven by a brushless DC motor installed within the mouse and provides stimulation to the thenar and hypothenar regions of the palm. The paper also reports on some demonstration applications that were designed to explore the potential of this mouse concept. These applications are designed to provide haptic sensations such as snapping, resistance, and inertia.

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This paper presents SensHB.Q, a cost-effective force-torque sensitive interface designed to control omnidirectional motorized systems such as mobile robots, industrial trolleys, and electric-powered wheelchairs. Force-torque-sensitive interfaces are considered more intuitive to use with respect to joysticks since they mimic the way we interact with objects. The main characteristic of SensHB.Q is the fact that measures three components of the applied wrench using only uniaxial load cells, avoiding the adoption of expensive multi-axis force-torque sensors. This work focuses on the executive design of this interface to understand the improvements that can be achieved by using flexure hinges instead of conventional revolute joints in terms of measurement accuracy.

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This paper presents a hands-free interface for controlling an omnidirectional electric wheelchair, designed to enhance mobility for individuals with motor impairments. The system utilizes multiple cameras to track face and torso movements, enabling natural and non-invasive driving system. A vision-based Intention Estimator integrates input from both the rider and caregiver, allowing for shared control. The proposed method ensures smooth navigation in confined indoor spaces, improving user experience. Experimental results demonstrate the feasibility of the approach, though challenges remain, particularly in addressing lighting conditions that affect facial landmark detection. Future work will focus on enhancing drivability and solving illumination issues to ensure reliable operation.

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Ability mining is a research field that aims to discover unknown human abilities by having people work under conditions that differ from their everyday lives. As part of research into ability mining, this study investigated the possibility of manipulating a virtual object using lower limb movement under rate control method. We conducted an experiment on situations where a virtual object is manipulated diagonally, and quantitatively evaluated the ability to manipulate using lower limb in terms of clear time, path length ratio, and subjective operability.

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This study proposes a soft robotic manipulator capable of multidirectional bending by actively controlling material extensibility using the solid-liquid phase transition of low-melting-point alloys (LMPAs). A stretchability control unit was developed by embedding LMPAs and heating elements, resulting in a significant increase in elongation upon heating. Additionally, capacitive proximity sensors were fabricated to detect contact direction, enabling responsive actuation. The final manipulator achieved four-directional bending with angles up to 10.3° at 25 kPa. The integrated system demonstrated adaptive behavior based on object interaction, showing promise for applications in safe and flexible human-robot interaction.

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Grape thinning is an important manual process that farmers remove low-quality grapes from each bunch of grapes before the ripeness of grapes. For example, undersized grapes or grapes with scars on their surface, and so on. However, grape thinning is an agricultural technique that needs experienced farmers for this manual work. In addition, Yamanashi Prefecture is an extremely crucial agricultural region of grapes in Japan, and Shine Muscat is one of the main agricultural products in this area. As a result, a robotic handling system for automated grape thinning targeting at Shine Muscat is being originally developed in this study.

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This paper proposes a thin linear electromagnetic actuator that utilizes a magnet sheet as its slider. The magnet sheet is actuated as a slider over a printed circuit board (PCB) that functions as a stator. Driven by a set of three sinusoidal currents with a phase shift of 𝜋/3, the prototype actuator achieved a synchronous motion with a thrust force density of 29.5 N/m2. With a flexible magnet sheet and a thin PCB, the proposed actuator demonstrated flexibility, which allows the actuator to be installed on a curved surface.

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To optimize the irradiation conditions of ultrasound for medical applications, a system that enables real-time observation of cellular responses to ultrasound is required. This study hypothesizes that cells exhibit frequency-dependent responses to ultrasound and aims to verify this. We propose a system with a cylindrical structure for real-time observation and an amplitude-enhancing mechanism that accommodates multiple driving frequencies. Using the fabricated system, we applied ultrasound at two different frequencies to cells and observed calcium influx. The results suggest that the vibration velocity at which calcium influx occurs may depend on the ultrasound frequency.

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This paper presents a morphological tensegrity wheel driven by thin McKibben muscles. Through driving experiments, we demonstrate that the tensegrity module is capable of functioning as a wheel with a variable diameter.

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Because of the potential shortage of energy resources in the future, it is essential to improve the efficiency of the induction motor. Induction motors have a challenge with efficiency in high temperatures. Applying CNT yarn to the secondary conductor can improve efficiency as the temperature rises. However, due to differences in electrical conductivity, the maximum torque decreases. In this study, we aimed to increase the maximum torque by designing the rotor structure of an induction motor with CNT yarn applied to the secondary conductor through size optimization using electromagnetic field analysis. The obtained structure achieved an improvement in maximum torque.

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Building a system that supports enhancing communication understanding by presenting both verbal and non-verbal information accurately and in real-time through various tools is crucial for improving communication quality. Particularly for foreigners and individuals with disabilities, gestures and facial expressions containing non-verbal information can manifest uniquely, making them difficult to interpret. Therefore, this study examines the effects of conveying non-verbal information by displaying the emotions of the conversation partner as if an "aura" were emanating from them on devices such as tablets and wearable monitors. The results confirm that using the aura expression on a tablet is especially effective, and these findings are reported here.

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Vibration-induced kinesthetic illusions occur when vibratory stimulation is applied to muscles through the skin, creating the perception of movement in a body part. A key factor in successfully inducing the illusion is the efficient transmission of vibratory energy to the target muscles. This requires appropriate design of the contact parts between the vibration actuator and the human skin. This study examines prior work on vibration-induced kinesthetic illusions, with a focus on the mechanical design of contact parts in vibration stimulation devices. We analyze the shapes and dimensions of contact parts used in earlier research. Our review found that existing designs prioritize user comfort by employing shapes and flexible materials that minimize discomfort in the skin tactile sensation. Additionally, contact surfaces have been selected to facilitate efficient transmission of vibration to tendons or muscle bellies without stimulating unrelated tissues. Based on these findings, we identified some directions as important for future development of contact interfaces optimized for kinesthetic illusion induction.

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In TR (Tokyo-Rome) Ankle Assisting Device, 4 bar linkage mechanism is used to transmit motor power to assisting link. The use of spring to assist motor power of this linkage is discussed in this work. The possible candidates of spring location are presented by topology search method. The effect of the use of spring is discussed in a case study.

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This paper presents an integrated system designed to translate Japanese industrial sign language into robotic commands, addressing significant accessibility challenges within manufacturing environments. We introduce a foundational dataset specifically tailored for Japanese industrial sign language and develop a real-time recognition system based on a bidirectional LSTM, architecture, enhanced by MediaPipe, landmark extraction, achieving an accuracy of 92% for single commands. The architecture of our AI agent, leverages large language models to convert recognized signs into semantically structured instructions, which are subsequently transformed into precise robot arm coordinates through our Vision-Language Model (VLM) calibration methodology. This system lays the groundwork for natural and accessible human-robot interaction via sign language, promoting workplace inclusion for hard-of-hearing individuals while ensuring operational efficiency in industrial settings. This paper emphasizes the sign language recognition methodology, highlighting its crucial role in facilitating accessible human-machine interfaces.

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