Motion control of multi-legged machines

Naoya Okamoto,Yosuke Kurihara,Kajiro Watanabe 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

This paper describes a control strategy for stable walking by a robot with six legs. While walking, the robot always has three legs in contact with the ground. Walking motion is controlled so that the center of gravity of the robot is within the triangle formed by the three contact points. It was confirmed that the proposed strategy enabled stable walking on a flat plane and on a plane with steps.

Phase I/II prospective clinical trial for the hybrid of intracavitary and interstitial brachytherapy for locally advanced uterine cervical cancer

Naoya Murakami,Miho Watanabe,Takashi Uno,Shuhei Sekii,Kayoko Tsujino,Takahiro Kasamatsu,Yumiko Machitori,Tomomi Aoshika,Shingo Kato,Hisako Hirowatari,Yuko Kaneyasu,Tomio Nakagawa,Hitoshi Ikushima,Ken 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.3

Objective: The purposes of this trial were to demonstrate the feasibility and effectiveness of the hybrid of intracavitary and interstitial brachytherapy (HBT) for locally advanced cervical cancer patients in the phase I/II prospective clinical trial. Methods: Patients with FIGO stage IB2-IVA uterine cervical cancer pretreatment width of which was ≥5 cm measured by magnetic resonance imaging were eligible for this clinical trial. The protocol therapy included 30–30.6 Gy in 15–17 fractions of whole pelvic radiotherapy concurrent with weekly CDDP, followed by 24 Gy in 4 fractions of HBT and pelvic radiotherapy with a central shield up to 50–50.4 Gy in 25–28 fractions. The primary endpoint of phase II part was 2-year pelvic progression-free survival (PPFS) rate higher than historical control of 64%. Results: Between October 2015 and October 2019, 73 patients were enrolled in the initial registration and 52 patients proceeded to the secondary registration. With the median follow-up period of 37.3 months (range, 13.9–52.9 months), the 2- PPFS was 80.7% (90% confidence interval [CI]=69.7%–88%). Because the lower range of 90% CI of 2-year PPFS was 69.7%, which was higher than the historical control ICBT data of 64%, therefore, the primary endpoint of this study was met. Conclusion: The effectiveness of HBT were demonstrated by a prospective clinical study. Because the dose goal determined in the protocol was lower than 85 Gy, there is room in improvement for local control. A higher dose might have been needed for tumors with poor responses.

Experimental Results of Series or Parallel Changeover System using Battery with EDLC for Electric Vehicle

Kyungmin Sung,Naoya Watanabe,Kyohei Kawamura 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

In the study of an electric vehicle (EV), an energy storage system which combines a battery and an electric double layer capacitor (EDLC) has been proposed. Introducing of EDLCs to an EV drive system, energy management become more efficient in term of using regenerative braking energy and saving battery energy. In this study, we propose a series or parallel changeover system using a battery and an EDLC for a small EV. This system can change over the composition of electric sources which battery and the EDLC bank in series or parallel depending on the voltage level of EDLC bank. The operating voltage range of EDLC bank is expanded from maximum to zero by the proposed system. In order to confirm the merit of the proposed method, two prototype EVs that one has a conventional DC-DC converter system and the other has the proposed changeover system are prepared and measured on automobile racing circuit. The effectiveness of proposed changeover system be verified and presented by experimental results.

Development of a Test Method for Assisted Walking Trolleys

Yoichi Asano,Hiroyuki Jinbo,Naoya Watanabe 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

Manufacturers have recently been developing assistive walking devices with electric motors, based on rollators and walking trolleys, in Japan. These assistive devices have electric motors to assist walking on sloped surfaces. Furthermore, they have a function that automatically suppresses the speed on downhill slopes. Here a walking experiment was conducted to investigate the speed at which the suppression function needed to be applied in various walking conditions. The subjects in the experiment walked while leaning on the assistive device, applying forces of 37 (horizontal) and 204 N (vertical) on downhill slopes. Furthermore, an analysis of the walking data obtained from traditional walking trolleys revealed that 80% of the subjects walked at a speed of 2.5 km/h or more. Two experiments were conducted to develop a test method that analyzed the performance of the suppression function on downhill slopes. The proposed test method results yielded sufficient accuracy.

Comparison of Dose Accuracy between Film and Two-dimensional Detectors in Intensity-modulated Radiation Therapy

Yuichi Onishi,Shinichi Nakayama,Shinsaku Watanabe,Souichirou Kaneshige,Hajime Monzen,Kenji Matsumoto,Naoya Shintani,Takeshi Kamomae 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.67 No.1

We constructed seven intensity-modulated radiation therapy (IMRT) treatment plans for prostate cancer (49 irradiation fields which contained seven randomly-sampled patients and seven fields) and evaluated the dose distributions by using a radiochromic film (EBT3 film) and a 2D detector. We superposed the calculated dose distribution of the IMRT treatment plan on EBT3 film and the 2D detector results and then compared those with the -analysis pass rate. The relative positions of the beam and the detector were varied; the results of the analysis of the superior-inferior (SI) direction potentially differed, depending on the detector position, under an irradiation beam with the same fluence map. The detector was moved over a range of ±8 mm in the SI direction in 1-mm step increments, measurement were made at each position, and the results were analyzed. The -analysis compared the dose distributions from EBT3 film and the radiation treatment planning system (RTPS) for each patient and field; the pass rate with the -analysis from 98 to 100% was 2.04%. When we compared the dose distributions of the 2D detector and the RTPS, the pass rate from 98 to 100% was 63.2%. The mean values for the -analysis pass rates for EBT3 film and the 2D detector were 94.2 and 97.6%, respectively. Volume averaging of the data indicated a mean pass rate and standard deviation of 98.6 and 0.91%, respectively, and a pass rate of more than 96% for all positions. A 2D detector can, therefore, be used as an alternative apparatus for IMRT dose verification.

Removal of fine particle fraction from municipal solid waste incineration bottom ash by open channel classification

( Teppei Komiya ),( Takuma Maeda ),( Yuki Kajino ),( Hirofumi Nakayama ),( Takayuki Shimaoka ),( Takayuki Hirao ),( Shuji Watanabe ),( Makoto Takemoto ),( Naoya Maeda ),( Akiyuki Ukai ),( Fumihiro Kas 한국폐기물자원순환학회(구 한국폐기물학회) 2019 한국폐기물자원순환학회 심포지움 Vol.2019 No.1

Approximately 20% of solid waste in Japan is disposed of at coastal landfill sites. It is an issue that it takes long-term to stabilize coastal landfill sites. Municipal solid waste incineration bottom ash (BA) is one of main wastes landfilled at coastal landfill sites. It is known that finer particles contain more contaminants in BA1), and it was demonstrated that the removal of finer particles from BA produced the lowering pH of leachate as well as the increase of permeability of the landfilled waste layer2). In this study, open channel (OC) classification was focused on as a feasible technique to remove finer particles from BA on a coastal landfill site, and its demonstrational experiment was carried out in order to clarify if the fine particle fraction (d<0.425mm) (FPF) could be removed from BA by OC classification and the settling characteristics of BA in OC. Fig. 1 shows the experimental apparatus. The sea water in a coastal landfill site was pumped up and flowed in OC, and BA is supplied on the surface of the flowing water. After completions of the settling and outflow of BA, saucers on the bottom of OC was collected, and the dry weight and particle size distribution of the BA sediment in each saucer were measured. Table 1 shows the experimental condition. The settling section means the part of OC from the BA supply point to the end of OC. Fig. 2 shows the removal ratio of FPF by OC classification, which is the ratio of the dry weight of FPF in the BA sediment to that in the BA supplied. The largest removal ratio was 61% in Case 3 with the largest water flow velocity and the shortest length of settling section. Fig. 3 shows the median of the settling velocity of BA in OC (MSV) compared with the theoretical settling velocity by Allen’s and Newton’s laws (TSV). The MSV of BA particles greater than 3mm was almost 50% of TSV, and MSV became closer to TSV as BA’s particle size became smaller. The MSV of BA particles with a diameter of 0.425mm was approximately 80% of TSV.