RRT (rapidly-exploring random tree) with random sampling is an effective method for path planning, and is often used for robot manipulators. The RRT has many modified methods for applying various problems and conditions. Particularly, T-RRT (Transition-based RRT) one of those has advantage that it is able to adopt arbitrary evaluation function. In this paper, a novel path planning method based on the T-RRT is proposed for ensuring ”quality” of a generated path. Then, its effectiveness is evaluated via comparison with other sampling-based methods using simulation of the industrial robot having seven degrees of freedom.

  This paper discusses a robot teaching system for scraping motion in a sand molding robot system using a vertical articulated robot. Sand molding robot systems for making self-hardening molds are increasingly being developed in recent years. These robots are able to automatically build a variety of sand molds by teaching robot motion for the sand mold making work. However, the teaching work takes considerable time and effort as the user needs to make the path of the robot motion by numerical entry using a teaching pendant as an input device, which makes it difficult to apply this robot system to high-mix low-volume manufacturing processes. In this study, we therefore proposed a simplified teaching system using a touch panel in which the paths of the robot motion can be generated by tapping the desired paths and visualized on the touch panel. It is easy to teach the desired paths to the sand molding robot and teaching work can be performed in a short time. We also focused on developing the teaching system for the sand scraping motion in the sand molding robot. The efficacy of the proposed teaching system was verified through experiments on sand scraping motion using the vertical articulated robot.

In the Additive Manufacturing (AM) method of Fused Filament Fabrication (FFF), thermoplastic resin is extruded from a nozzle along a forming path generated from a 3D geometric model of the object. FFF software slices the object in a horizontal plane, and arranges support material during the fabrication process if needed. To reduce the support material, Robotic AM using a vertically articulated robot has been studied. Although Robotic AM realizes multi-directional access, its’ motion is affected by singularities. Since most cases of singularities can be avoided by changing the starting point of the work, in this study, a dual-arm robotic AM is proposed to increase possibility. An extrusion nozzle is attached to one arm, and a bed is attached to another arm. The position and orientation of the extrusion nozzle and the bed can have enough degrees of freedom. The best starting position and orientation will be optimized by simulations according to design of experiments. The behavior was confirmed by running the simulation and the actual machine.

Fused Filament Fabrication (FFF) in the Additive Manufacturing (AM) is a widely popular method in which thermoplastic resin is melted and extruded through a nozzle. However, it has issues such as anisotropy and the inability to produce smooth curved surfaces. Robotic AM, which uses a vertically articulated robot with more redundant degrees of freedom than conventional AM systems, has been investigated to fabricate curved surfaces while changing the orientation of the layers. One of the effective uses is conformal AM, in which curved layers are arranged along the original geometry. In addition, a method using two vertically articulated robots has been proposed for Robotic AM to avoid singularities. In this study, we propose FFF method for arbitrarily shaped curved surface deposition with avoiding singularities by simultaneously controlling the nozzle-side arm and bed-side arm of a dual arm robot. A system with redundant degrees of freedom was developed using ROS2, and the effectiveness of the method for winding continuous fibers without cutting them was confirmed.

A locally operated surgical support robot holding an endoscope is introduced in a sterile area for otologic surgery, and a surgeon can perform robot-assisted transcanal endoscopic ear surgery (TEES) with low physical load and view stabilization. We have developed a new locally operated endoscope manipulator with a pivot movable mechanism that can be used by the surgeon as the third arm. The pivot movable mechanism for the endoscope lens is with a passive gimbal mechanism driven by a linear guided DC motor for its inserting and removal motion, and with three passive linear guides of Cartesian coordinates and another passive gimbal mechanism for the endoscope camera motion. The endoscope camera is manipulated by a vertical articulated robot.