Design and Performance of a Motor-Driven Mechanism to Conduct Experiments With the Human Index Finger

2015 ◽  
Vol 7 (3) ◽  
Author(s):  
Pei-Hsin Kuo ◽  
Jerod Hayes ◽  
Ashish D. Deshpande
Keyword(s):  
Index Finger ◽  
Human Subjects ◽  
Joint Stiffness ◽  
Viscoelastic Behavior ◽  
Neuromuscular Control ◽  
External Loading ◽  
Human Hand ◽  
Robotic Hands ◽  
Hand Biomechanics ◽  
Human Hands

Passive properties of the human hands, defined by the joint stiffness and damping, play an important role in hand biomechanics and neuromuscular control. Introduction of mechanical element that generates humanlike passive properties in a robotic form may lead to improved grasping and manipulation abilities of the next generation of robotic hands. This paper presents a novel mechanism, which is designed to conduct experiments with the human subjects in order to develop mathematical models of the passive properties at the metacarpophalangeal (MCP) joint. We designed a motor-driven system that integrates with a noninvasive and infrared motion capture system, and can control and record the MCP joint angle, angular velocity, and passive forces of the MCP joint in the index finger. A total of 19 subjects participated in the experiments. The modular and adjustable design was suitable for variant sizes of the human hands. Sample results of the viscoelastic moment, hysteresis loop, and complex module are presented in the paper. We also carried out an error analysis and a statistical test to validate the reliability and repeatability of the mechanism. The results show that the mechanism can precisely collect kinematic and kinetic data during static and dynamic tests, thus allowing us to further understand the insights of passive properties of the human hand joints. The viscoelastic behavior of the MCP joint showed a nonlinear dependency on the frequency. It implies that the elastic and viscous component of the hand joint coordinate to adapt to the external loading based on the applied frequency. The findings derived from the experiments with the mechanism can provide important guidelines for design of humanlike compliance of the robotic hands.

Transforming Human Hand Motion for Telemanipulation

1992 ◽  
Vol 1 (1) ◽  
pp. 63-79 ◽  
Author(s):  
Thomas H. Speeter
Keyword(s):  
Force Feedback ◽  
Robotic Manipulation ◽  
Human Hand ◽  
Robotic Hand ◽  
Robotic Hands ◽  
Automated Control ◽  
Functional Transformation ◽  
Hand Motion ◽  
Computationally Expensive ◽  
Human Hands

Manipulation by teleoperation (telemanipulation) offers an apparently straightforward and less computationally expensive route toward dextrous robotic manipulation than automated control of multifingered robotic hands. The functional transformation of human hand motions into equivalent robotic hand motions, however, presents both conceptual and analytical problems. This paper reviews and proposes algorithmic methods for transforming the actions of human hands into equivalent actions of slave multifingered robotic hands. Forward positional transformation is considered only, the design of master devices, feedforward dynamics, and force feedback are not considered although their importance for successful telemanipulation is understood. Linear, nonlinear, and functional mappings are discussed along with performance and computational considerations.

Design of a Motor-Driven Mechanism to Conduct Experiments to Determine the Passive Joint Properties of the Human Index Finger

2011 ◽  
Author(s):  
Pei-Hsin Kuo ◽  
Jerod Hayes ◽  
Ashish D. Deshpande
Keyword(s):  
Index Finger ◽  
Human Subjects ◽  
Human Hand ◽  
The Novel ◽  
Prosthetic Hands ◽  
Joint Properties ◽  
Driven System ◽  
New Generation ◽  
Novel Design

Our long term goal is to develop a new generation of robotic-prosthetic hands that will incorporate key anatomical features of the human hand, especially, the passive dynamics defined by the joint stifftness and damping properties. This paper presents a design of a mechanism that can measure the passive moment of the human hand joint. We designed a motor-driven system, integrating a noninvasive and infrared motion capture system, that can control and record the angle, angular velocity and passive forces of the metacarpophalangeal (MCP) joint in the index finger. A total of 19 subjects participated in the experiments. We conducted two experiments to estimate the total passive moments of the MCP joint from the human subjects. The results showed that the novel design of the mechanism collected the precise passive moments and kinematic data, thus allowing us to develop a comprehensive understanding of the passive properties of the human hand joints.

scholarly journals Correlation of Index Finger Length (2D) with Height, Weight and BMI in Adult Bangladeshi Male

2017 ◽  
Vol 7 (2) ◽  
pp. 90-94
Author(s):  
Karim Rezwan Hasan ◽  
Shamim Ara ◽  
Fakhrul Amin Mohammad Hasanul Banna
Keyword(s):  
Evolutionary Biology ◽  
Index Finger ◽  
Medical Science ◽  
Human Hand ◽  
Cross Sectional ◽  
Morphological Attributes ◽  
Medical College ◽  
Finger Length ◽  
Positive Correlations ◽  
Male Subjects

Background: Human hand is one of the most versatile parts of the human body which plays an important role in modern medical science and evolutionary biology. By virtue of evolution and genetic arrangements, digital lengths vary from person to person according to age, sex, races, occupation or even environmental influences. It has been found that the digital lengths and their ratios are not same in different sexes and even in both hands of same individual. Specially, index to ring digit lengths and their ratios which already have been proved to represent sexual dimorphism may differ in both hands of an individual and show positive correlations with other morphological attributes like height, weight and BMI.Objectives: To analyze the variation of index finger (2D) length and its correlation with height, weight and BMI in adult Bangladeshi male.Materials and Methods: This cross-sectional analytical study was conducted in the department of Anatomy, Dhaka Medical College, Dhaka from July 2012 to June 2013 on 100 male MBBS students (20?25 years of age). With the help of digital vernier caliper measurements of index finger length (2D) was recorded. Height and weight were measured by the stadiometer and weighing scale respectively. BMI was calculated from height and weight. Pearson’s correlation analysis was done to find out the correlation of index finger length with height, weight and BMI.Results: Significant correlation has been found between the lengths of index fingers (2D) and height (p<0.01), but there was no significant correlation of index finger length with weight and BMI (p>0.05).Conclusion: In this study, we found variation in index finger lengths of both hands of Bangladeshi male subjects, which needs further study and comparison.J Enam Med Col 2017; 7(2): 90-94

Evidence that low-threshold muscle afferents evoke long-latency stretch reflexes in human hand muscles

1991 ◽  
Vol 65 (5) ◽  
pp. 1089-1097 ◽  
Author(s):  
J. Noth ◽  
M. Schwarz ◽  
K. Podoll ◽  
F. Motamedi
Keyword(s):  
Index Finger ◽  
Angular Displacement ◽  
Metacarpophalangeal Joint ◽  
Muscle Afferents ◽  
Human Hand ◽  
Hand Muscles ◽  
Long Latency ◽  
M2 Response ◽  
Spinal Afferents ◽  
Wrist Flexors

1. The aim of the present study was to identify the type of spinal afferents involved in the generation of the long-latency response in intrinsic human hand muscles. Position-controlled extensions were imposed on the index finger or on the wrist of healthy subjects who were exerting a steady voluntary flexion force at the relevant joint. Averaged surface electromyographic (EMG) responses of the first dorsal interosseus muscle (FDI) or of the wrist flexors were evaluated with respect to latency and size. 2. Small transient angular displacements of the index finger (1 degree, as measured at the metacarpophalangeal joint), which are supposed to excite primary rather than secondary afferents, evoked two clearly discernible EMG responses with mean latencies of 32.3 ms (M1 response) and 54.7 ms (M2 response), respectively. The size of the M2 response exceeded the size of the M1 response by 60%. In the wrist flexors, transient stretch (1 degree) gave rise to a large M1 response (latency 22.8 ms) and a small, inconstent M2 response. 3. Small-amplitude vibration of the index finger elicited EMG responses in the FDI that were qualitatively and quantitatively similar to those seen in response to small transient stretches of the index finger. This was also true for fast ramp-and-hold stretches (stretch velocity 400 degrees/s, amplitude 5 degrees), whereas slow ramp-and-hold stretches (125 degrees/s, 5 degrees) elicited predominantly M2 responses. 4. In the FDI, the mechanical threshold of the M1 and M2 response to the transient angular displacement was approximately 0.15 degrees, with a tendency for the M2 response to appear at a lower threshold.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of muscle perfusion pressure on fatigue and systemic arterial pressure in human subjects

1999 ◽  
Vol 86 (3) ◽  
pp. 845-851 ◽  
Author(s):  
Julie R. Wright ◽  
D. I. McCloskey ◽  
Richard C. Fitzpatrick
Keyword(s):  
Blood Pressure ◽  
Perfusion Pressure ◽  
Human Subjects ◽  
Normal Subjects ◽  
Voluntary Contraction ◽  
Muscle Performance ◽  
Central Blood Pressure ◽  
Human Hand ◽  
Adductor Pollicis Muscle ◽  
Arterial Perfusion

The effects of changes in arterial perfusion across the physiological range on the fatigue of a working human hand muscle were studied in seven normal subjects. With the hand above heart level, subjects made repeated isometric contractions of the adductor pollicis muscle at 50% of maximal voluntary contraction in a 6-s on, 4-s off cycle. To assess fatigue, a maximal isometric twitch was elicited in each “off” period by electrical stimulation of the ulnar nerve. The experiment was repeated at least 2 days later with the hand at heart level. Five subjects showed faster fatigue with the arm elevated, and two subjects showed little difference in fatigue for the two conditions. Central blood pressure rose in proportion to fatigue for the subjects overall and returned quickly to its initial level afterwards. We conclude that human muscle fatigue can be increased by physiological reductions in perfusion pressure. Central blood pressure increases as the muscle fatigues, a response that may partially offset declining muscle performance.

PHASED MULTI-JOINT MOVEMENT OF THE INDEX FINGER DURING A FULL FLEXION CYCLE

2008 ◽  
Vol 20 (05) ◽  
pp. 303-312
Author(s):  
Wensheng Hou ◽  
Xiaoying Wu ◽  
Yingtao Jiang ◽  
Jun Zheng ◽  
Xiaolin Zheng ◽  
...  
Keyword(s):  
Angular Velocity ◽  
High Speed ◽  
Index Finger ◽  
Human Subjects ◽  
Joint Motion ◽  
Joint Movement ◽  
General Belief ◽  
Angular Velocities ◽  
Full Flexion ◽  
Five Phases

Flexion of the index finger is a fairly complex process requiring the coordination of different joints. This study is the first attempt to investigate how the angular velocity profile of the three right index joints (DIP, PIP, and MCP) varies with respect to time during the course of flexion. Ten right-handed subjects (healthy college students between 21 and 23 years old) were recruited to participate in the experiment. Each of these human subjects was instructed to perform a flexion task with his/her right hand. Five miniaturized (5-mm diameter) reflective markers were applied to each human subject: three placed at the DIP, PIP, and MCP joints of the index finger on the side close to thumb, and the rest at the predetermined landmarks on dorsum of thumb. A high-speed camera was used to record the motion of the index finger during a paced flexion, and the instantaneous angular velocity of each joint was determined by relating the marker displacement to the frame frequency (~5 ms between two consecutive frames). Opposite to the general belief that the speed is constant throughout a flexion cycle, to our best knowledge, this study, for the first time, has revealed that the speed of multi-joint movement actually varies with time. It has been identified that during one full flexion cycle, the angular velocity of the three joints of interest undergoes five distinguishable phases, referred as phases P1 (slow), P2 (fast), P3 (slow), P4 (fast), and P5 (slow), respectively. It has also been observed that duration of each of phases P1, P2, P4, or P5 accounts for approximately 10–15% of the whole flexion cycle, while P3 lasts for nearly half a cycle. Furthermore, although the flexions of DIP, PIP, and MCP joints cycle through the same five phases, the starts of their respective phases tend to vary. In P2 and P5, flexion of MCP takes place considerably later than those of PIP and DIP, whereas DIP flexes earlier than PIP in P2. The angular velocity of each joint reaches its peaks in P2 and P4; the peak velocity of DIP occurs earlier than that of PIP or MCP in P2, whereas peak of MCP is reached later than that of PIP. Moreover, the three joints of index finger flex with different angular velocities in each of the five phases: PIP moves significantly faster than MCP in P2, whereas DIP moves faster than MCP in P4. The results from our study indicate that the multi-joint motion of index finger is an uneven course, i.e. different joints flex with different angular velocities during the flexion. The temporal features of the velocity due to a single joint or multi-joint motion provide useful information to further clarify the dexterity of finger movement.

scholarly journals Design of Non-Anthropomorphic Robotic Hands for Anthropomorphic Tasks

2011 ◽  
Author(s):  
Edgar Simo-Serra ◽  
Francesc Moreno-Noguer ◽  
Alba Perez-Gracia
Keyword(s):  
Genetic Algorithm ◽  
Solution Space ◽  
Kinematic Chain ◽  
Human Hand ◽  
Dimensional Synthesis ◽  
Robotic Hands ◽  
Serial Chain ◽  
Finite Set ◽  
Numerical Solver ◽  
Local Optimizer

In this paper, we explore the idea of designing non-anthropomorphic multi-fingered robotic hands for tasks that replicate the motion of the human hand. Taking as input data a finite set of rigid-body positions for the five fingertips, we develop a method to perform dimensional synthesis for a kinematic chain with a tree structure, with five branches that share three common joints. We state the forward kinematics equations of relative displacements for each serial chain expressed as dual quaternions, and solve for up to five chains simultaneously to reach a number of positions along the hand trajectory. This is done using a hybrid global numerical solver that integrates a genetic algorithm and a Levenberg-Marquardt local optimizer. Although the number of candidate solutions in this problem is very high, the use of the genetic algorithm allows us to perform an exhaustive exploration of the solution space to obtain a set of solutions. We can then choose some of the solutions based on the specific task to perform. Note that these designs match the task exactly while generally having a finger design radically different from that of the human hand.

An Optimization Approach to Teleoperation of the Thumb of a Humanoid Robot Hand: Kinematic Mapping and Calibration

2014 ◽  
Vol 136 (9) ◽  
Author(s):  
Lei Cui ◽  
Ugo Cupcic ◽  
Jian S. Dai
Keyword(s):  
Input Device ◽  
Human Hand ◽  
Optimization Approach ◽  
Robotic Hand ◽  
Kinematic Structure ◽  
Robotic Hands ◽  
Data Glove ◽  
Minimax Algorithms ◽  
Kinematic Mapping ◽  
And Control

The complex kinematic structure of a human thumb makes it difficult to capture and control the thumb motions. A further complication is that mapping the fingertip position alone leads to inadequate grasping postures for current robotic hands, many of which are equipped with tactile sensors on the volar side of the fingers. This paper aimed to use a data glove as the input device to teleoperate the thumb of a humanoid robotic hand. An experiment protocol was developed with only minimum hardware involved to compensate for the differences in kinematic structures between a robotic hand and a human hand. A nonlinear constrained-optimization formulation was proposed to map and calibrate the motion of a human thumb to that of a robotic thumb by minimizing the maximum errors (minimax algorithms) of fingertip position while subject to the constraint of the normals of the surfaces of the thumb and the index fingertips within a friction cone. The proposed approach could be extended to other teleoperation applications, where the master and slave devices differ in kinematic structure.

Dexterous Gripper Synthesis From Modular Finger Approach

2017 ◽  
Author(s):  
Nahian Rahman ◽  
Carlo Canali ◽  
Darwin G. Caldwell ◽  
Ferdinando Cannella
Keyword(s):  
Mathematical Formulation ◽  
Degree Of Freedom ◽  
Human Hand ◽  
Soft Or ◽  
Rigid Material ◽  
Human Hands

Dexterous gripper requirements, such as in-hand manipulation is a capability on which human hands are unique at; numerous number of sensors, degree of freedom, adaptability to deal with plurality of object of our hand motivate the researchers to replicate these abilities in robotic grippers. Developments of gripper or grasping devices have been addressed from many perspectives: the use of materials in the gripper synthesis, such as rigid or flexible, the approach of control, use of under-actuated mechanism and so on. Mathematical formulation of grasp modeling, manipulation are also addressed; however, due to the presence non-holonomic motion, it is difficult to replicate the behaviors (achieved in model) in a physical gripper. Also, achieving skills similar to human hand urge to use soft or non rigid material in the gripper design, which is contrary to speed and precision requirements in an industrial gripper. In this dilemma, this paper addresses the problem by developing modular finger approach. The modular finger is built by two well known mechanisms, and exploiting such modular finger in different numbers in a gripper arrangement can solve many rising issues of manipulation.

scholarly journals Grasp Stiffness Control in Robotic Hands Through Coordinated Optimization of Pose and Joint Stiffness

2018 ◽  
Vol 3 (4) ◽  
pp. 3952-3959 ◽  
Author(s):  
Virginia Ruiz Garate ◽  
Maria Pozzi ◽  
Domenico Prattichizzo ◽  
Nikos Tsagarakis ◽  
Arash Ajoudani
Keyword(s):  
Joint Stiffness ◽  
Robotic Hands ◽  
Coordinated Optimization ◽  
Stiffness Control
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