By using a tether (cable) to link the ground station and the space station at 36,000[km] altitude, a space elevator is envisioned where transportation is achieved by a climber that ascends and descends the tether. In anticipation of industrial applicability near the ground, a climber for a rope-type tether (rope-type climber) was developed in this study. Compared with a climber for a belt-type tether, the rope-type climber has a small contact area between the tether and the roller, leading to problems with slippage and roller deterioration. Accordingly, here the contact area between the rope and roller was increased by using four drive wheels, and synchronized velocity control was accomplished with two drive motors for two drive wheels. Also the rope-type climber has more difficulty maintaining its orientation and is easily rotated around the tether by wind and other factors, so a control moment gyro (CMG) unit was developed that can be applied to the climber. An optimal servo system using a disturbance observer was applied to a rope-type climber with the developed CMG unit to achieve lift stabilization control. Then the effectiveness of the developed system was verified in lift experiments at the 25[m] outdoor test site of Kanagawa University and in a 1.2[km] lift experiment at the Space Elevator Challenge.
Participation in collaborative projects is regarded to be one of the necessary activities for universities and colleges. Furthermore, participation of students in such projects is expected to be effective from the view of an engineering design education and social implementation education. Collaborative projects are usually carried out by several stakeholders, and they are required to be managed properly based on their interests. However, they tend to be managed by trial and error, because each stakeholder has different circumstances and different purposes. In this paper, stakeholder analysis was introduced and applied to two social implementation education projects that were carried out in the author's college. One is a management of a lecture where a speaker was invited from another college, and the other is a management of developing a mascot robot for a regional festival. The results from the stakeholder analysis and the author's cognition were compared. As a result, it was confirmed that the stakeholder analysis has a potential capability of a management of projects of social implementation education.
Octopus suction cup has the micro bumps or trenches. These micro structure will be effective for a performance of adhesion. We reported the vacuum gripper imitating an adhesion principle of octopus. This gripper can grasp the rigid object with flat, curved, and uneven surface. In this paper, we evaluated the effect of micro bumps using the octopus-bioinspired vacuum griper added the bumps which is 2[μm] in diameter and 4[μm] in pitch. The adhesion force of gripper with micro bumps was higher than that of gripper without micro bumps, since the friction force between gripper and object was increased by bumps. Moreover, the shear force of peering was increased by adding micro bumps to gripper.
Recently, about 60% of worker suffers from low back pain in Japan. Hard working such as lifting and carrying provides a load to waist joint, and worker gets low back pain. So, we developed a power assist suit to reduce the load of waist joint. This assist suit has various futures; endoskeleton, high output and flexibility, because this device moves using two pneumatic actuators. This device generates active and passive assistive force. These forces can assist human motions according as situations. First of all, we analyzed the human motion by motion capturing software. The analysis results are substituted into human link model, and load of human body is estimated. Thus, we decided design and operation method of the assist suit using analysis results and a static assist suit model. The motion of wearer is “lifting up motion” and “carrying motion” in evaluation experiments, because these motions are frequently performed in manufacturing plant work. Each assistive force assists these motions, and effectiveness of assist suit was confirmed from decrease of electromyography (EMG) in wearing.
In this paper, we propose a new control method which realizes “well-organized” crossing motion of multiple swarms of robots. Although there are several researches which realize crossing motion of multiple swarms of robots without collision, the transient state is not considered. To realize “well-organized” crossing motion, we define what “well-organized” crossing is in this study, and then propose the crossing motion planning method which consists of an offline path planning, an online follow-up control and online collision avoidance. Especially, in the offline path planning, which is based on model predictive control, a trajectory without disorder of the formation is generated. Furthermore we show the validity of the proposed mothod by some simulations and experimental results.