In recent years, robotic technology has been introduced to medical fields and many surgical robots have been presented. In this paper, an outer shell type 2 DOF bending manipulator using a spring-link mechanism is presented. The mechanism was developed for a surgical robot, which can implement various surgical treatment devices inside of the manipulator. The spring-link mechanism is a simple combination of a flat spring and a rigid link with a passive joint connection. The outer shell type 2 DOF bending manipulator incorporates four spring-link mechanisms. The most unique feature of the manipulator is that these four springs are interconnected in the kinematics. Therefore, it is possible to realize a robust and backlash-free motion by taking into account the interconnections of the springs such as an internal stress of the structure. In addition, by locating the four spring-link mechanisms around the manipulator, it is possible to place medical devices inside of the manipulator. This paper describes the kinematic model, analysis, prototype implementation and evaluation of the proposed mechanism.
In daily conversation, we sometimes observe a deictic interaction scene that refers to a region in a space, such as saying “please put it over there” with pointing. How can such an interaction be possible with a robot? Is it enough to simulate people's behaviors, such as utterance and pointing? Instead, we highlight the importance of simulating human cognition. In the first part of our study, we empirically demonstrate the importance of simulating human cognition of regions when a robot engages in a deictic interaction by referring to a region in a space. The experiments indicate that a robot with simulated cognition of regions improves efficiency of its deictic interaction. In the second part, we present a method for a robot to computationally simulate cognition of regions. Finally, our model is implemented as region referring system in the communication robot Robovie and the system's effectiveness is confirmed.
In this paper, we report a field trial with a network robot system in a shopping mall. Our network robot system consists of three components: environmental sensors, network robot platform and social robots. Multiple laser range finders are used as the environmental sensors to estimate people's positions. Position data is used to estimate such human walking behaviors as “stopping” or “idle walking,” to direct robots to provide appropriate tasks to appropriate people. By using this information, the network robot platform coordinates multiple social robots to provide efficient service to customers. It coordinates the tasks of robots based on their positions and people's walking behavior, the paths of robots, and the conversation-performance between two robots. Each social robot interacts with people to provide recommendation information about shops and route information of the mall. The system sometimes simultaneously uses two robots to lead people from one place to the specific shop. We conducted a field trial in a shopping mall, in which four robots interacted with 414 people. It demonstrated the effectiveness of the network robot system for guiding people around a shopping mall as well as increasing their interest.
This paper presents a shape transformation control method of a mobile robot with wheel-arms. The proposed method aims at transformation from a four-wheeled mode for high speed mobility to an inverted pendulum mode, which has advantages of high viewing position and small turning radius. The transformation starts with lifting up the wheel-arms to raise the center of gravity of the whole body. From such initial states, the body is lifted up and controlled to the target angle by partial linearization, while returning the arms to the initial angle. Then, the wheels are slowed down by properly changing the target pitch angle of the body. Stability analysis is carried out by taking into account the transient response of the body angle to the target value, which is neglected in existing work. The effectiveness of the proposed method is demonstrated by experiments.