scholarly journals Simulation analysis of thrusts and joint torques during underwater dolphin kick

2008 ◽  
Vol 32 (2) ◽  
pp. 90-97 ◽  
Author(s):  
Seiji SUGIMOTO ◽  
Motomu NAKASHIMA ◽  
Hiroshi ICHIKAWA ◽  
Takeo NOMURA
Keyword(s):  
Simulation Analysis ◽  
Joint Torques ◽  
Dolphin Kick

scholarly journals Optimal grasp planning for a dexterous robotic hand using the volume of a generalized force ellipsoid during accepted flattening

2017 ◽  
Vol 14 (1) ◽  
pp. 172988141668713 ◽  
Author(s):  
Peng Jia ◽  
Wei li Li ◽  
Gang Wang ◽  
Song Yu Li
Keyword(s):  
Simulation Analysis ◽  
Internal Force ◽  
Planning Method ◽  
Robotic Hand ◽  
Grasp Planning ◽  
Joint Torques ◽  
Contact Points ◽  
Generalized Force ◽  
Internal Forces ◽  
Dexterous Hand

A grasp planning method based on the volume and flattening of a generalized force ellipsoid is proposed to improve the grasping ability of a dexterous robotic hand. First, according to the general solution of joint torques for a dexterous robotic hand, a grasping indicator for the dexterous hand—the maximum volume of a generalized external force ellipsoid and the minimum volume of a generalized contact internal force ellipsoid during accepted flattening—is proposed. Second, an optimal grasp planning method based on a task is established using the grasping indicator as an objective function. Finally, a simulation analysis and grasping experiment are performed. Results show that when the grasping experiment is conducted with the grasping configuration and positions of contact points optimized using the proposed grasping indicator, the root-mean-square values of the joint torques and contact internal forces of the dexterous hand are at a minimum. The effectiveness of the proposed grasping planning method is thus demonstrated.

A calculation method of the reaction force and moment for a Delta-type parallel link robot fixed with a frame

Robotica ◽  
2009 ◽  
Vol 27 (4) ◽  
pp. 579-587 ◽  
Author(s):  
Jangho Hong ◽  
Motoji Yamamoto
Keyword(s):  
Simulation Analysis ◽  
Virtual Work ◽  
Reaction Force ◽  
Parallel Robot ◽  
Euler Method ◽  
Experimental Results ◽  
Joint Torques ◽  
Serial Robots ◽  
Delta Type ◽  
Parallel Link

SUMMARYThe paper presents a method of reaction force and moment calculation for a 3-RSS pure translational parallel link robot (Delta-type parallel robot), in which the inverse and forward kinematics of the parallel link robot are directly analyzed according to kinematic structure of the parallel robot. For dynamic analysis, the parallel robot is imaginarily parted into three serial ones, and their actual joint torques are determined by the virtual work principle. To obtain the reaction force and moment of the parallel robot acting on the base, which is the composition of the reaction forces and moments of the three serial robots, the Newton–Euler Method is adopted. To show the validity of the presented method, the simulation analysis and experimental results are given, the experimental results tally with the calculation value.

scholarly journals The effects of plantar flexion angle increment on the performance during underwater dolphin kick using simulation analysis

2008 ◽  
Vol 53 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Seiji Sugimoto ◽  
Motomu Nakashima ◽  
Hiroshi Ichikawa ◽  
Takahiro Miwa ◽  
Tsuyoshi Takeda ◽  
...  
Keyword(s):  
Simulation Analysis ◽  
Plantar Flexion ◽  
Flexion Angle ◽  
Dolphin Kick

scholarly journals Optimal Limb Length Ratio of Quadruped Robot Minimising Joint Torque on Slopes

2009 ◽  
Vol 6 (3-4) ◽  
pp. 259-268 ◽  
Author(s):  
Tadayoshi Aoyama ◽  
Kosuke Sekiyama ◽  
Yasuhisa Hasegawa ◽  
Toshio Fukuda
Keyword(s):  
Simulation Analysis ◽  
Slope Angle ◽  
Quadruped Robot ◽  
Working Environment ◽  
Joint Torque ◽  
Limb Length ◽  
Optimal Structure ◽  
Length Ratio ◽  
Leg Length ◽  
Joint Torques

This paper aims to determine an optimal structure for a quadruped robot, which will allow the robot’s joint torque sum to be minimised. An animal’s characteristic limb length ratio is a vital part of its overall morphology and the one that enables it to travel easily through its environment. For the same reason, a robot’s structure needs to be suitably designed for locomotion in its working environment. Joint torques are necessary to maintain the posture of the robot and to accelerate joint angles during walking motion, hence, minimisation of joint torques reduces energy consumption. We performed a numerical simulation in which we analysed the joint torques for various limb lengths and slope angles in order to determine the optimal structure of a robot walking on a slope. Our investigation determines that the optimal Ratio of Rear Leg Length (RRL) can be derived by the use of a simulation designed to determine the physical structure of quadruped robot. Our analysis suggests that joint torque will increase as the slope angle becomes steeper if the rear legs of the robot are shorter than its forelegs, and that joint torque will decrease as the slope angle declines if the robot’s forelegs are shorter than its rear legs. Finally, experimental results validated our simulation analysis.

Computer simulation study about the dependence of amorphous silicon photonic waveguides efficiency on the material quality

2020 ◽  
Vol 90 (3) ◽  
pp. 30502
Author(s):  
Alessandro Fantoni ◽  
João Costa ◽  
Paulo Lourenço ◽  
Manuela Vieira
Keyword(s):  
Amorphous Silicon ◽  
High Throughput Screening ◽  
Simulation Analysis ◽  
Low Cost ◽  
Deposition Process ◽  
Large Area ◽  
Sidewall Roughness ◽  
Sensing Applications ◽  
Fabrication Defects ◽  
The Impact

Amorphous silicon PECVD photonic integrated devices are promising candidates for low cost sensing applications. This manuscript reports a simulation analysis about the impact on the overall efficiency caused by the lithography imperfections in the deposition process. The tolerance to the fabrication defects of a photonic sensor based on surface plasmonic resonance is analysed. The simulations are performed with FDTD and BPM algorithms. The device is a plasmonic interferometer composed by an a-Si:H waveguide covered by a thin gold layer. The sensing analysis is performed by equally splitting the input light into two arms, allowing the sensor to be calibrated by its reference arm. Two different 1 × 2 power splitter configurations are presented: a directional coupler and a multimode interference splitter. The waveguide sidewall roughness is considered as the major negative effect caused by deposition imperfections. The simulation results show that plasmonic effects can be excited in the interferometric waveguide structure, allowing a sensing device with enough sensitivity to support the functioning of a bio sensor for high throughput screening. In addition, the good tolerance to the waveguide wall roughness, points out the PECVD deposition technique as reliable method for the overall sensor system to be produced in a low-cost system. The large area deposition of photonics structures, allowed by the PECVD method, can be explored to design a multiplexed system for analysis of multiple biomarkers to further increase the tolerance to fabrication defects.

Sign in / Sign up

Export Citation Format

Share Document