Novel Design of a Robotic Gripper Allowing for In-Hand Manipulation

2007 ◽  
Author(s):  
Philip A. Voglewede
Keyword(s):  
Vision System ◽  
End Effector ◽  
Different Types ◽  
Finger Gaiting ◽  
End Effectors ◽  
Anthropomorphic Hands ◽  
Self Motion ◽  
Novel Design

The design of robotic end effectors can be loosely classified into two different types: complex anthropomorphic hands which allow for manipulation and simple open/close grippers which do not. This article investigates a design of a simple, industrial feasible end effector that allows for in-hand manipulation of parts. This end effector can be utilized in conjunction with a vision system to eliminate parts feeders and be able to pick parts straight from bins. The design utilizes passive joints that, when in a particular configuration, align (a self-motion singularity) to allow in-hand manipulation without regrasping or finger gaiting. A prototype end effector was fabricated and tested to prove the concept.

scholarly journals Novel Design for a Simple and Affordable End-Effector for an Upper-Limb Prosthesis

2017 ◽  
Vol 12 (1) ◽  
pp. 62-73
Author(s):  
Shawn Jackson ◽  
Victoria Volk ◽  
Jodi Prosise
Keyword(s):  
Upper Limb ◽  
Primary User ◽  
Customer Requirements ◽  
End Effector ◽  
Total Cost ◽  
Upper Limb Prosthesis ◽  
Pvc Pipe ◽  
End Effectors ◽  
Novel Design ◽  
Limb Prosthesis

An affordable prosthetic arm was designed to be used in underprivileged areas to allow more upper-limb amputees to have access to prosthetics that can help them regain their independence. The primary user of the prosthesis will be the amputee(s) who receive the device; beneficiaries include the amputee’s family and the community involved in the manufacturing of future prostheses. The customer requirements include cost-effectiveness, the ability to withstand humidity, cleanability, low maintenance, long life, lightweight, and the ability to perform simple tasks independently. A new end-effector was created that meets the range-of-motion required for the user to perform his/her required tasks. The end-effector is comprised of a PVC cap, PVC coupling, wooden ball holding the tool, and two wooden stop rings. The device screws onto the forearm PVC pipe and locks into place. Four end-effectors were created: toothbrush, fork, spoon, and pen. A change-out station was created to allow the user to independently attach and detach the different end-effectors. The total cost of the device was $20.66.

The Role of the End-Effector in the Perception of Virtual Surfaces Presented via Force-Feedback Haptic Interfaces

1999 ◽  
Author(s):  
Janet M. Weisenberger ◽  
Michael J. Krier ◽  
Martha A. Rinker ◽  
Sandra M. Kreidler
Keyword(s):  
Force Feedback ◽  
Considerable Effect ◽  
Haptic Interface ◽  
Haptic Interfaces ◽  
End Effector ◽  
Sinusoidal Gratings ◽  
Different Types ◽  
Force Profile ◽  
End Effectors

Abstract Differences in the force profile delivered by different types of end-effectors suggest that the choice of end-effector for a haptic interface can have a considerable effect on the perception of the human user. In the present study two different end-effector types were evaluated for two different haptic interfaces. Conventional probe-stylus end-effectors were tested on the PHANToM 3-degree-of-freedom (DOF) force feedback haptic interface and for the Immersion IE2000 2-DOF force feedback joystick. These were compared to thimble-gimbal end-effectors into which the index fingertip is inserted (standard for the PHANToM and specially constructed for the IE2000). In a task in which subjects were asked to judge the orientation of virtual sinusoidal gratings, no significant differences in performance were observed. Results are discussed in terms of tasks in which the differential cues delivered by different end-effectors might influence performance.

Hybrid buffer‐based optical packet switch with negative acknowledgment for multilevel data centers

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sumit Chandra ◽  
Shahnaz Fatima ◽  
Raghuraj Singh Suryavanshi
Keyword(s):  
Data Centers ◽  
Web Applications ◽  
Optical Switch ◽  
Contention Resolution ◽  
Multilevel Data ◽  
All Optical ◽  
Optical Buffering ◽  
Different Types ◽  
Packet Switch ◽  
Novel Design

AbstractIn the present scenario, data centers serve many functionalities like storage, transfer of data, supporting web applications, etc. In data centers, various levels of hierarchy different types of switches are required; therefore, multifunctional data centers are desired. This paper discusses a novel design for optical switch which can be placed at various levels of hierarchy. In the proposed design, multifunctionality contention resolution schemes which consider electronic and optical buffering and all-optical negative acknowledgment (AO-NACK) are considered. In buffering technologies, contending packets are stored in either in electronic RAM or in fiber delay lines. In case of the AO-NACK scheme, contending packets are blocked, and a negative acknowledgment is sent back to the transmitting node and blocked packets are retransmitted. For various considered schemes, Monte Carlo simulation have been performed, results in terms of packet loss probability are presented, and it has been found that the performance of optical buffering is much superior to electronic buffering and AO-NACK schemes. It is found that, in the AO-NACK scheme, the numbers of retransmitted packets due to contention blocking are 33,304 which can be reduced to 7, by using a small amount of buffer at each node.

scholarly journals Force-Free Control for Direct Teaching of a Surgical Assistant Robot End Effector with Wire-Driven Bidirectional Telescopic Mechanism

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3498
Author(s):  
Youqiang Zhang ◽  
Cheol-Su Jeong ◽  
Minhyo Kim ◽  
Sangrok Jin
Keyword(s):  
Control Algorithm ◽  
Position Control ◽  
Friction Model ◽  
Surgical Instruments ◽  
Control Input ◽  
End Effector ◽  
Motor Current ◽  
Direct Teaching ◽  
End Effectors ◽  
Teaching Operation

This paper shows the design and modeling of an end effector with a bidirectional telescopic mechanism to allow a surgical assistant robot to hold and handle surgical instruments. It also presents a force-free control algorithm for the direct teaching of end effectors. The bidirectional telescopic mechanism can actively transmit force both upwards and downwards by staggering the wires on both sides. In order to estimate and control torque via motor current without a force/torque sensor, the gravity model and friction model of the device are derived through repeated experiments. The LuGre model is applied to the friction model, and the static and dynamic parameters are obtained using a curve fitting function and a genetic algorithm. Direct teaching control is designed using a force-free control algorithm that compensates for the estimated torque from the motor current for gravity and friction, and then converts it into a position control input. Direct teaching operation sensitivity is verified through hand-guiding experiments.

scholarly journals THE INFLUENCE OF DESIGN BRIEF INFORMATION ON CREATIVE OUTCOMES BY NOVICE AND ADVANCED STUDENTS

2021 ◽  
Vol 1 ◽  
pp. 3041-3050
Author(s):  
Georgios Koronis ◽  
Hernan Casakin ◽  
Arlindo Silva ◽  
Jacob Kai Siang Kang
Keyword(s):  
Design Education ◽  
Design Problems ◽  
Frame Design ◽  
Design Creativity ◽  
Abstract Representations ◽  
Advanced Students ◽  
Different Types ◽  
Fishbone Diagram ◽  
Design Expertise ◽  
Novel Design

AbstractThis study centers on using different types of brief information to support creative outcomes in architectural and engineering design and its relation to design expertise. We explore the influence of design briefs characterized by abstract representations and/or instructions to frame design problems on the creativity of concept sketches produced by novice and advanced students. Abstract representations of problem requirements served as stimuli to encourage associative thinking and knowledge transfer. The Ishikawa/Fishbone Diagram was used to foster design restructuring and to modify viewpoints about the main design drives and goals. The design outcomes generated by novice and advanced engineering/architecture students were assessed for their creativity using a pairwise experimental design. Results indicated that advanced students generated more novel design solutions while also contributing the most useful solutions overall. Implications for creativity in design education and professional practice are presented. Educational programs aimed at promoting creativity in the design studio may find it helpful to consider that the way design briefs are constructed can either promote or inhibit different aspects of design creativity.

scholarly journals Magnetic Driven Two-Finger Micro-Hand with Soft Magnetic End-Effector for Force-Controlled Stable Manipulation in Microscale

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 410
Author(s):  
Dan Liu ◽  
Xiaoming Liu ◽  
Pengyun Li ◽  
Xiaoqing Tang ◽  
Masaru Kojima ◽  
...  
Keyword(s):  
Magnetic Force ◽  
Force Feedback ◽  
Soft Magnetic ◽  
End Effector ◽  
Force Microscopy ◽  
System A ◽  
Atomic Force ◽  
Afm Probe ◽  
End Effectors ◽  
Fixed End

In recent years, micromanipulators have provided the ability to interact with micro-objects in industrial and biomedical fields. However, traditional manipulators still encounter challenges in gaining the force feedback at the micro-scale. In this paper, we present a micronewton force-controlled two-finger microhand with a soft magnetic end-effector for stable grasping. In this system, a homemade electromagnet was used as the driving device to execute micro-objects manipulation. There were two soft end-effectors with diameters of 300 μm. One was a fixed end-effector that was only made of hydrogel, and the other one was a magnetic end-effector that contained a uniform mixture of polydimethylsiloxane (PDMS) and paramagnetic particles. The magnetic force on the soft magnetic end-effector was calibrated using an atomic force microscopy (AFM) probe. The performance tests demonstrated that the magnetically driven soft microhand had a grasping range of 0–260 μm, which allowed a clamping force with a resolution of 0.48 μN. The stable grasping capability of the magnetically driven soft microhand was validated by grasping different sized microbeads, transport under different velocities, and assembly of microbeads. The proposed system enables force-controlled manipulation, and we believe it has great potential in biological and industrial micromanipulation.

scholarly journals Deviation Tolerance Performance Evaluation and Experiment of Picking End Effector for Famous Tea

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 128
Author(s):  
Yingpeng Zhu ◽  
Chuanyu Wu ◽  
Junhua Tong ◽  
Jianneng Chen ◽  
Leiying He ◽  
...  
Keyword(s):  
Success Rate ◽  
Negative Pressure ◽  
Evaluation Method ◽  
Orthogonal Experiment ◽  
Spatial Position ◽  
End Effector ◽  
Significance Level ◽  
Growth Environment ◽  
End Effectors ◽  
Average Success Rate

Accurately obtaining the posture and spatial position of tea buds through machine vision and other technologies is difficult due to the small size, different shapes, and complex growth environment of tea buds. Therefore, end effectors are prone to problems, such as picking omission and picking error. This study designs a picking end effector based on negative pressure guidance for famous tea. This end effector uses negative pressure to guide tea buds in a top-down manner, thereby correcting their posture and spatial position. Therefore, the designed end effector has deviation tolerance performance that can improve the picking success rate. The pre-experiment is designed, the tip of apical bud is referred to as the descent position, and the negative pressure range is determined to be 0.6 to 0.9 kPa. A deviation tolerance orthogonal experiment is designed. Experimental results show that various experimental factors are ranked in terms of the significance level of the effect on the average success rate, and the significance ranking is as follows: negative pressure (P) > pipe diameter (D) > descent speed (V). An evaluation method of deviation tolerance performance is presented, and the optimal experiment factor-level combination is determined as: P = 0.9 kPa, D = 34 mm, V = 20 mm/s. Within the deviation range of a 10 mm radius, the average success rate of the negative pressure guidance of the end effector is 97.36%. The designed end effector can be applied to the intelligent picking of famous tea. This study can provide a reference for the design of similar picking end effectors for famous tea.

Self-Motion of a Camphanic Acid Disk on Water with Different Types of Surfactants

2006 ◽  
Vol 110 (42) ◽  
pp. 21131-21134 ◽  
Author(s):  
Satoshi Nakata ◽  
Junko Kirisaka ◽  
Yoshie Arima ◽  
Toshio Ishii
Keyword(s):  
Different Types ◽  
Self Motion ◽  
Camphanic Acid

scholarly journals Stiffness Modeling of Robotic-Manipulators Under Auxiliary Loadings

2012 ◽  
Author(s):  
Alexandr Klimchik ◽  
Anatol Pashkevich ◽  
Stéphane Caro ◽  
Damien Chablat
Keyword(s):  
Robotic Manipulators ◽  
Computationally Efficient ◽  
End Effector ◽  
Efficient Procedure ◽  
Stiffness Modeling ◽  
Cartesian Stiffness Matrix ◽  
Different Types ◽  
Mapping Equation ◽  
Linear Force ◽  
Cartesian Stiffness

The paper focuses on the extension of the virtual-joint-based stiffness modeling technique for the case of different types of loadings applied both to the robot end-effector and to manipulator intermediate points (auxiliary loading). It is assumed that the manipulator can be presented as a set of compliant links separated by passive or active joints. It proposes a computationally efficient procedure that is able to obtain a non-linear force-deflection relation taking into account the internal and external loadings. It also produces the Cartesian stiffness matrix. This allows to extend the classical stiffness mapping equation for the case of manipulators with auxiliary loading. The results are illustrated by numerical examples.

scholarly journals Theory and practice of hydrostatic lysimeters for direct measurement of net seepage in a patterned mire in north Scotland

2001 ◽  
Vol 5 (4) ◽  
pp. 693-709 ◽  
Author(s):  
H. A. P. Ingram ◽  
A. M. Coupar ◽  
O. M. Bragg
Keyword(s):  
Electrical Power ◽  
Theory And Practice ◽  
Moisture Distribution ◽  
Water Tables ◽  
Different Types ◽  
Hydraulic Mechanism ◽  
Pool System ◽  
Novel Design ◽  
Soil Moisture Distribution ◽  
Design Construction

Abstract. A novel design of lysimeter for use in mires (peatlands) with shallow water tables is described. It employs an hydraulic mechanism for the automatic equilibration of soil moisture distribution between the outside and the inside of the lysimeter tank but uses no electronic components or electrical power; and it can be installed with minimal disturbance in surfaces with poor load-bearing capacity. The system was deployed on a mire in northern Scotland to investigate the distribution of shallow seepage associated with catenary arrays of different types of surface (microtopes). During the three-year period 15 November 1988 to 19 November 1991, the fraction of rainfall dispersed as seepage was 52% in a pool system; 62% in ridge-furrow microtopography; and 59-67% in unpatterned sloping mire. The data provide preliminary confirmation of the hypothesis of K. E. Ivanov that different microtopes within the same mire differ in their hydrological norms; and suggest that the range of ecohydrological differences at the study site may be similar to those obtained by Ivanov in western Siberia. Details of lysimeter design, construction, installation and operation are appended together with a discussion of the theory of the lysimeter. Keywords: acrotelm, blanket mire, ecohydrology, evapotranspiration, pool system, valleyside flowe, water balance

Sign in / Sign up

Export Citation Format

Share Document