著者
Shunichi Sakurai Seiichiro Katsura
出版者
The Institute of Electrical Engineers of Japan
雑誌
IEEJ Journal of Industry Applications (ISSN:21871094)
巻号頁・発行日
pp.23003740, (Released:2023-12-08)

Parallel robots with closed-loop kinematic chains have been used in industrial applications. They exhibit superior precision, stiffness, and operating speed than serial robots owing to their mechanical architecture. However, parallel robots demonstrate static singularity unique to parallel mechanisms, which further impede their application. Static singularity is caused by passive joints included in the mechanism. In this study, a 3-leg 6-DOF spatial parallel robot with actuation redundancy and its statics are analyzed. The analysis indicates that static singularity does not occur if actuation redundancy is properly introduced. This analysis is based on the decomposition of force transmission in the robot. Experimental results show that precise trajectory tracking and stable contact are achieved by virtue of the actuation redundancy. This study opens new avenues for the application of parallel robots.
著者
Issei Takeuchi Seiichiro Katsura
出版者
The Institute of Electrical Engineers of Japan
雑誌
IEEJ Journal of Industry Applications (ISSN:21871094)
巻号頁・発行日
vol.11, no.5, pp.643-649, 2022-09-01 (Released:2022-09-01)
参考文献数
32
被引用文献数
2

In order to improve control performance in various control fields, it is important to model the controlled object accurately. In this case, the quality of the model is considerably influenced by the structure of the model determined by the engineer. An element description method is a method that can optimize not only parameters but also the structure of the model. Therefore, it is possible to search over a wide range without being restricted by human design. However, this considerably increases the search space, and it is easy to fall into a local solution. In this study, the artificial bee colony algorithm is combined with the element description method to improve its search ability. The artificial bee colony algorithm is known to be effective for high-dimensional and multimodal problems. The performance of the proposed method is validated using a heat sealing system in packaging machinery. The proposed method is evaluated in comparison with the genetic algorithm, which is a conventional method. Experiments confirm that the local solution avoidance performance of the artificial bee colony algorithm is significantly better than that of the genetic algorithm.
著者
Hiroki Kurumatani Yuuki Inoue Satoshi Nishimura Masahiko Isaka Ryo Shimane Takuya Tanaka Seiichiro Katsura
出版者
The Institute of Electrical Engineers of Japan
雑誌
IEEJ Journal of Industry Applications (ISSN:21871094)
巻号頁・発行日
vol.8, no.4, pp.576-585, 2019-07-01 (Released:2019-07-01)
参考文献数
18

High-speed and high-precision weighing is required in industrial and medical fields. Recently, medical services have improved rapidly and the demand for medicines have increased. Because improper medication can lead to life-threatening symptoms, precise filling and weighing all medicines are vital processes. On the other hand, there are requirements from suppliers to increase production volume. For this problem, Reduction the time by applying vibration-suppression control for a weighing cell is presented. The weighing cell exhibits oscillating responses as it has vibration mechanism inside. This vibration increases the weighing time and then reflected-wave rejection is introduced to suppress the vibration. Because reflected-wave rejection is a phase-stabilizing method, the controller attains a robustness against modeling errors. As a result, the weighing cell did not vibrate regardless of existence of a load. In addition, lift-up operations of vial bottles with water by the weighing cell were also conducted. The water surface did not fluctuate and immediately settled. Reflected-wave rejection certainly contributes to reducing the time for weighing.