scholarly journals The Development of a Hybrid Underwater Micro Biped Robot

2006 ◽  
Vol 3 (3) ◽  
pp. 143-150 ◽  
Author(s):  
S. Guo ◽  
Y. Okuda ◽  
W. Zhang ◽  
X. Ye ◽  
K. Asaka
Keyword(s):  
Degrees Of Freedom ◽  
Biped Robot ◽  
Input Voltage ◽  
Industrial Applications ◽  
Structure And Motion ◽  
Miniature Device ◽  
Micro Robot ◽  
Voltage Frequency ◽  
Ion Conducting ◽  
Ion Conducting Polymer

There has been a great demand, in the medical field and in industrial applications, for a novel micro biped robot with multiple degrees of freedom that can swim smoothly in water or in aqueous medium. The fish-like micro-robot studied is a type of miniature device that is installed with sensing and actuating elements. This article describes the new structure and motion mechanism of a hybrid type of underwater micro-robot using an ion-conducting polymer film (ICPF) actuator, and discusses the swimming and floating characteristics of the micro-robot in water, measured by changing the voltage frequency and the amplitude of the input voltage. Results indicate that the swimming speed of the proposed underwater micro-robot can be controlled by changing the frequency of the input voltage, and the direction (upward or downward) can be manipulated by changing the frequency of the electric current applied and the amplitude of the voltage.

scholarly journals Design and performance assessment of an underactuated hand for industrial applications

2011 ◽  
Vol 2 (1) ◽  
pp. 9-15 ◽  
Author(s):  
C. Meijneke ◽  
G. A. Kragten ◽  
M. Wisse
Keyword(s):  
Degrees Of Freedom ◽  
International Workshop ◽  
Input Voltage ◽  
Industrial Applications ◽  
Open Loop ◽  
Robotic Hand ◽  
Loop Control ◽  
Six Degrees Of Freedom ◽  
And Performance ◽  
Underactuated Robot

Abstract. The Delft Hand 2 (DH-2) is an underactuated robot hand meant for industrial applications, having six degrees of freedom (DoF), one actuator (DoA) and no sensors. It was designed to provide a cheap and robust hand to grasp a large range of objects without damaging them. The goal of this paper is to assess the design and performance of the DH-2, demonstrating how the design was optimized for its intended application area and how the hand was simplified to make it commercially attractive. Performance tests show that the DH-2 has a payload of 2 kg for an object range of 60 to 120 mm, it can close or open within 0.5 s, and it only uses open-loop control by means of the input voltage of the motor. The results demonstrate that the industrial need of a simple, cheap and effective robotic hand can be achieved with the principle of underactuation and the use of conventional components. This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.

DC-Modulated AC/AC Converters

2013 ◽  
Vol 341-342 ◽  
pp. 1317-1325
Author(s):  
Lin Luo Fang
Keyword(s):  
Output Voltage ◽  
Input Voltage ◽  
Voltage Regulation ◽  
Industrial Applications ◽  
The Novel ◽  
Novel Approach ◽  
Regulation Method ◽  
Input Side ◽  
Voltage Frequency ◽  
Ac Converters

Traditional methods of AC/AC converters have general drawbacks: output voltage is lower than input voltage, the input side THD is poor and output voltage frequency is lower than input voltage frequency by using voltage regulation method and cycloconverters. We introduce the novel approach - DC-modulated AC/AC converters in this paper, which successfully overcomes the drawbacks. Simulation and experimental results of the DC-modulated AC/AC converter are the evidences to verify our design. These methods will be very widely used in industrial applications.

Flame-retardant single-ion conducting polymer electrolytes based on anion acceptors for high-safety lithium metal batteries

2021 ◽  
Author(s):  
Kuirong Deng ◽  
Tianyu Guan ◽  
Fuhui Liang ◽  
Xiaoqiong Zheng ◽  
Qingguang Zeng ◽  
...  
Keyword(s):  
Solid State ◽  
Flame Retardant ◽  
Conducting Polymer ◽  
Polymer Electrolytes ◽  
Lithium Metal ◽  
Lithium Metal Batteries ◽  
Lithium Metal Anodes ◽  
Ion Conducting ◽  
Ion Conducting Polymer ◽  
Metal Anodes

Solid-state lithium metal batteries (LMBs) assembled with polymer electrolytes (PEs) and lithium metal anodes are promising batteries owing to their enhanced safeties and ultrahigh theoretical energy densities. Nevertheless, polymer electrolytes...

Generating real-time trajectories for a planar biped robot crossing a wide ditch with landing uncertainties

Robotica ◽  
2018 ◽  
Vol 37 (1) ◽  
pp. 109-140 ◽  
Author(s):  
V. Janardhan ◽  
R. Prasanth Kumar
Keyword(s):  
Real Time ◽  
Degrees Of Freedom ◽  
Dynamic Balance ◽  
Surface Friction ◽  
Biped Robot ◽  
Net Energy ◽  
Leg Length ◽  
Uncertain Environments ◽  
Novel Concept ◽  
Time Planning

SUMMARYDitch crossing is one of the essential capabilities required for a biped robot in disaster management and search and rescue operations. Present work focuses on crossing a wide ditch with landing uncertainties by an under-actuated planar biped robot with five degrees of freedom. We consider a ditch as wide for a robot when the ankle to ankle stretch required to cross it is at least equal to the leg length of the robot. Since locomotion in uncertain environments requires real-time planning, in this paper, we present a new approach for generating real-time joint trajectories using control constraints not explicitly dependent on time, considering impact, dynamic balance, and friction. As part of the approach, we introduce a novel concept called the point of feasibility for bringing the biped robot to complete rest at the end of ditch crossing. We present a study on the influence of initial posture on landing impact and net energy consumption. Through simulations, we found the best initial postures to efficiently cross a wide ditch of width 1.05 m, with less impact and without singularities. Finally, we demonstrate the advantage of the proposed approach to cross a wide ditch when the surface friction is not same on both sides of the ditch.

Quasi-human biped walking

Robotica ◽  
2005 ◽  
Vol 24 (2) ◽  
pp. 257-268 ◽  
Author(s):  
Hun-ok Lim ◽  
Sang-ho Hyon ◽  
Samuel A. Setiawan ◽  
Atsuo Takanishi
Keyword(s):  
Motion Control ◽  
Continuous Time ◽  
Degrees Of Freedom ◽  
Biped Robot ◽  
Humanoid Robots ◽  
Compensation Method ◽  
Biped Walking ◽  
Working Space ◽  
Physical Construction

Our goal is to develop biped humanoid robots capable of working stably in a human living and working space, with a focus on their physical construction and motion control. At the first stage, we have developed a human-like biped robot, WABIAN (WAseda BIped humANoid), which has a thirty-five mechanical degrees of freedom. Its height is 1.66 [m] and its weight 107.4 [kg]. In this paper, a moment compensation method is described for stability, which is based on the motion of its head, legs and arms. Also, a follow walking method is proposed which is based on a pattern switching technique. By a combination of both methods, the biped robot is able to perform dynamic stamping, walking forward and backward in a continuous time while someone is pushing or pulling its hand in such a way. Using WABIAN, human-fellow walking experiments are conducted, and the effectiveness of the methods are verified.

scholarly journals Modified Space Vector Modulated Z Source Inverter with Effective DC Boost and Lowest Switching Stress

2010 ◽  
Vol 7 (1) ◽  
pp. 70 ◽  
Author(s):  
S. Thangaprakash ◽  
A. Krishnan
Keyword(s):  
Control Algorithm ◽  
Degrees Of Freedom ◽  
Control Strategies ◽  
Input Voltage ◽  
Duty Ratio ◽  
Space Vector ◽  
Voltage Vector ◽  
Voltage Stress ◽  
Capacitor Voltage ◽  
Full Utilization

 This paper presents a modified control algorithm for Space Vector Modulated (SVM) Z-Source inverters. In traditional control strategies, the Z-Source capacitor voltage is controlled by the shoot through duty ratio and the output voltage is controlled by the modulation index respectively. Proposed algorithm provides a modified voltage vector with single stage controller having one degree of freedom wherein traditional controllers have two degrees of freedom. Through this method of control, the full utilization of the dc link input voltage and keeping the lowest voltage stress across the switches with variable input voltage could be achieved. Further it offers ability of buck-boost operation, low distorted output waveforms, sustainability during voltage sags and reduced line harmonics. The SVM control algorithm presented in this paper is implemented through Matlab/Simulink tool and experimentally verified with Z-source inverter prototype in the laboratory. 

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