This paper newly proposes a multi-fingered robot hand with a common rotational axis shared by all base joints of finger. By focusing on a manipulation around such a particular axis, finger motion planning drastically becomes simple. In order to generate the common rotational axis, we introduce the dual turning mechanism where two and two other fingers can independently turn along the inner and the outer circles with the common center axis, respectively. Due to this mechanism, the developed hand is good at twisting motion based tasks, for example opening a cap from a bottle, within one hand, while it is generally hard for human or conventional robot hands to execute the same task quickly. We show a couple of experiments for confirming our basic idea.
When humans interact in a social context, there are many factors apart from the actual communication that need to be considered. Previous studies in behavioral sciences have shown that there is a need for a certain amount of personal space and that different people tend to meet the gaze of others to different extents. For humans, this is mostly subconscious, but when two persons interact, there is an automatic adjustment of these factors to avoid discomfort. In this paper we propose an adaptation mechanism for robot behaviors to make human-robot interactions run more smoothly. We propose such a mechanism based on policy gradient reinforcement learning, that reads minute body signals from a human partner, and uses this information to adjust interaction distances, gaze meeting, and motion speed and timing in human-robot interaction. We show that this enables autonomous adaptation to individual preferences by the experiment with twelve subjects.
To create a more efficient environment in which to perform remote maintenance, the authors propose a novel collaboration concept, called robot-supported cooperative work (RSCW) . In RSCW a maintenance robot assists a cooperation work between an on-site human worker and another skilled human operator at a remote support center. By emphasizing the intentions of the remote supporter through robot functions that cannot be imitated by humans, RSCW can provide effective support for the on-site worker. In the present study, as the first manifestation of RSCW, featuring the projection capability of a maintenance robot, a prototype remote-collaboration system named SCOPE (sight collaboration by projection effect) was developed. This system consists of a projector unit with a camera, a multiple control unit (MCU) for video/voice communications, and PCs connected via a network. It has three key functions: creating a shared field of view between a remote supporter and an on-site worker, keeping metainformation related to objects in real space, and projecting meta-information onto the objects. The effectiveness of these functions was evaluated by experiments on two fundamental tasks—“comprehending a target object”and“transmission of instruction details”—involved in a typical maintenance operation. The experimental results show that each function is effective in shortening the time taken to perform the maintenance operation.
This paper describes a modularized inchworm-type robot that we developed and used for searching for victim. The robot we called AIT-ReBol has two types of modules, one is the head module that is equipped at the terminal of the robot's body with small wireless camera and wireless network functions to communicate with outside, another module is the joint that has two rotational and a linear driven degree of freedom with the decentralized controller module and energy source in a compact form. We pay attention to moving mechanism and realized the motion patterns such as moving straight, side and rotational by the progressive wave in body without any wheel or crawler. This robot has already successfully debut at the AICHI EXPO 2005 and stably played for about one month.
Ultrasonically activated scalpels are used clinically to provide hemostatic cutting in endoscopic surgery. To assist the physician during endoscopic surgery, we develop an ultrasonically activated bending scalpel constructed of super elasticity alloy (SEA) . We analyzed the vibration characteristics of the probe in the bending state by the finite element method. And the proposed active bending mechanism is prototyped. Moreover the vibration characteristics were measured to examine its effectiveness. Also, a cutting experiment was conducted. We demonstrate the ultrasonic vibration of the proposed scalpel is possible using a conventional vibration controller, since the change of the natural frequency due to the bend is negligible. In the prototyping, we realized the bending mechanism by using a linkage. The range of the bending angles varies from 0 [deg] to 60 [deg] .
A 6 legged walking vehicle composed of a pair of leg units each of which has three expandable soles and has an ability to make rotational and traversable motion among the leg units is made. It is developed to realize a solid and reliable walking vehicle for practical uses in the near future with spread mechanical elements used in usual hydraulic construction machines. It weighs about 80 [kg] with all aluminum (including honeycomb frame) structure. Owing to mounted 24 [V] /12 [Ah] battery unit and wireless control system, it has no umbilical cord for power supply, control and communication. It is shown by the experiments that the vehicle can walk continuously over 1 hour, crossing many obstacles those maximum height is about 0.9 [m], and many irregular soil terrain.
In this paper, we propose an online recognition method for daily actions, such as walking and standing. The proposed method has following characteristics: (1) simultaneous recognition that is able to output multiple action names when human act more than one action, such a situation ashuman is waving hand on standing, (2) modeling action classifiers with kernel methods, (3) effective optimization for the parameters of the recognition system with margin-based query learning. The characteristic (2) unifies the process for modeling and learning the classifiers, and makes us easy to incorporate prior knowledge about action. The characteristic (3) reduces the burden of process for annotating action, which is an inevitable task for supervised learning. The experimental results using real motion capture data show that the proposed margin-based query learning is very effective to achieve high performance of the recognition system with very small sized query and annotation process.
A feature of soft object manipulation in free space is coupling of motion and deformation of the soft object. Herein, we formulate simultaneous control of position and deformation of a viscoelastic object. We show that the stability of the system depends not only on control laws and parameters but also on physical parameters of the object, and that positive feedback gain within a certain range stabilizes PID controlled systems; outside this range, the object cannot be stably controlled since the object is movable. We also validate the stability of the system for control inputs and mapped manipulated and positioned points. The positioned points converge to their desired positions using the mapping based on closest relationship between the positioned and manipulated points. We show that both the viscosity of a soft object and the damping component of the control law are essential for stability when a force is used as a control input.
One of the most graceful phenomena widely observed in nature is self-assembly; living systems spontaneously form their body structure through the developmental process. While this remarkable phenomenon still leaves much to be understood in biology, the concept of self-assembly becomes undeniably indispensable also in artificial systems as they increase in size and complexity. Based on this consideration, this paper discusses the realization of selfassembly with the use of a modular robot. The main contributions of this paper are twofold: the first concerns the exploitation of emergent phenomena stemming from the interplay between the control and mechanical systems; the second is related to the implementation of different adhesiveness among the modules. Here, form generation by self-assembly is considered as the result of time evolution toward the most dynamically stable state. Owing to this, the proposed method also satisfies significant ability of self-repair. Preliminary simulation results show that stable and spontaneous self-assembly is achieved irrespective of the initial positional relationship among the modules. To our knowledge, this is a first study that deals with self-assembly in the field of modular robots by explicitly exploiting the interplay between control and mechanical systems.