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![Human hand structure. The joints in the human hand and the relative DoFs. The carpometacarpal joint in the little finger is omitted. Numbers refer to the functional components as divided by Kapandji [6].](profile/Marco-Donati/publication/49627734/figure/fig3/AS:667797587755012@1536226760421/Human-hand-structure-The-joints-in-the-human-hand-and-the-relative-DoFs-The.jpg)
Human hand structure. The joints in the human hand and the relative DoFs. The carpometacarpal joint in the little finger is omitted. Numbers refer to the functional components as divided by Kapandji [6].
Source publication
This paper presents the preliminary design of a new dexterous upper-limb prosthesis provided with a novel anthropomorphic hand, a compact wrist based on bevel gears and a modular forearm able to cover different levels of upper-limb amputations. The hand has 20 DoFs and 11 motors, with a dexterous three fingered subsystem composed by a fully actuate...
Contexts in source publication
Context 1
... two groups accounting nineteen muscles each: the extrinsic and intrinsic muscles. The extrinsic muscles are the long flexors and extensors, and are called extrinsic because they are located on the forearm; the intrinsic muscles instead, are located in the palm. Kapandji divides the human hand into three functional components [6] (cf. numbers in Fig. 1): 1) The thumb, which by itself fulfils most of the functions of the hand because of its movement of opposition; 2) The index and the middle finger, which help the thumb to achieve precision grips; 3) The ring and the little fingers, which along with the rest of the hand, are essential for solidly grasping tool handles on the ulnar ...
Context 2
... of counterposition). Geometrically speaking, opposition of the thumb consists of bringing into contact the pulp of the thumb and the other finger so that they touch. In other words, the tangential planes of the two pulps merge in space at a single point. Five DoFs in three joints are used to achieve opposition and dexterity of the thumb (cf. Fig. 1 The knowledge of the human hand, is of fundamental importance for biomedical engineers, as it represents the benchmark to be targeted. Considering the application though, targeting the mechanical complexity of the natural hand would be a redundant approach, because of the limited performance offered by current (even sophisticated) ...
Citations
... Artificial hands benefit from hardware strategies that reduce the need for actuators and sensors. These strategies also enable passive adaptation to various object shapes and sizes [126]. Using this approach may restrict the hand's flexibility and fine motor skills, which may not match the user's desired movements or expectations [53]. ...
The human hand is a complex and versatile organ that enables humans to interact with the environment, communicate, create, and use tools. The control of the hand by the brain is a crucial aspect of human cognition and behaviour, but also a challenging problem for both neuroscience and engineering. The aim of this study is to review the current state of the art in hand and grasp control from a neuroscientific perspective, focusing on the brain mechanisms that underlie sensory integration for hand control and the engineering implications for developing artificial hands that can mimic and interface with the human brain. The brain controls the hand by processing and integrating sensory information from vision, proprioception, and touch, using different neural pathways. The user’s intention can be obtained to control the artificial hand by using different interfaces, such as electromyography, electroneurography, and electroencephalography. This and other sensory information can be exploited by different learning mechanisms that can help the user adapt to changes in sensory inputs or outputs, such as reinforcement learning, motor adaptation, and internal models. This work summarizes the main findings and challenges of each aspect of hand and grasp control research and highlights the gaps and limitations of the current approaches. In the last part, some open questions and future directions for hand and grasp control research are suggested by emphasizing the need for a neuroscientific approach that can bridge the gap between the brain and the hand.
... Each finger's length and range of motion are uniformly designed, as shown in Tables 2, 3, and Figure 6 respectively. The human hand contains at least 23 degrees of freedom (DOFs) [7]. Human fingers have 3 joints with 4 DOFs: 3 DOFs for flexion-extension movement and 1 DOF for adduction-abduction movement. ...
... This experiment is a test of the basic hand gestures and symbols that are chosen from frequently used in daily life. The robotic hand successfully posed 9 common gestures including high-five (1), peace (2), ok (3), index pointing (4), grasp (5), promise (6), love (7), check (8), and good job (9) as shown in Figure 28. The purpose of this robotic hand design does not focus on the adductionabduction movement but to reduce the number of motors. ...
... Physiological structure of the human hand[33]. ...
As the end execution tool of agricultural robots, the manipulator directly determines whether the grasping task can be successfully completed. The human hand can adapt to various objects and achieve stable grasping, which is the highest goal for manipulator design and development. Thus, this study combines a multi-sensor fusion tactile glove to simulate manual grasping, explores the mechanism and characteristics of the human hand, and formulates rational grasping plans. According to the shape and size of fruits and vegetables, the grasping gesture library is summarized to facilitate the matching of optimal grasping gestures. By analyzing inter-finger curvature correlations and inter-joint pressure correlations, we investigated the synergistic motion characteristics of the human hand. In addition, the force data were processed by the wavelet transform algorithms and then the thresholds for sliding detection were set to ensure robust grasping. The acceleration law under the interaction with the external environment during grasping was also discussed, including stable movement, accidental collision, and placement of the target position. Finally, according to the analysis and summary of the manual gripping mechanism, the corresponding pre-gripping planning was designed to provide theoretical guidance and ideas for the gripping of robots.
... The CMC and MCP joints have two DOFs, i.e., flexion/extension and abduction/adduction, respectively, while the IP joints have only one DOF, i.e., flexion/extension. The four fingers each contain the DIP, PIP, and MCP joints, while the thumb contains the IP, MCP, and CMC joints, and thus, each of the four fingers has three joints and four DOFs, and the thumb has three joints and five DOFs [20]. ...
... For example, the RoboRay Hand [29] has seven high payload motors in the forearm and five small motors in the palm for high-powered grasping and precise grasping. The bioinspired hand [20] used forearm-mounted motors to drive the MCP joints and palm-mounted motors to drive the coupled PIP and DIP joints. In general, IAP is chosen for better modularity of the robotic hands; EAP allows the use larger actuators for greater gripping force, while the remaining hand space can be spared to install more sensors; HAP is more suitable for the cases in which the convenience of installation and gripping force of different joints need to be considered. ...
Humanoid robotic upper limbs including the robotic hand and robotic arm are widely studied as the important parts of a humanoid robot. A robotic upper limb with light weight and high output can perform more tasks. The drive system is one of the main factors affecting the weight and output of the robotic upper limb, and therefore, the main purpose of this study is to compare and analyze the effects of the different drive methods on the overall structure. In this paper, we first introduce the advantages and disadvantages of the main drive methods such as tendon, gear, link, fluid (hydraulic and pneumatic), belt, chain, and screw drives. The design of the drive system is an essential factor to allow the humanoid robotic upper limb to exhibit the structural features and functions of the human upper limb. Therefore, the specific applications of each drive method on the humanoid robotic limbs are illustrated and briefly analyzed. Meanwhile, we compared the differences in the weight and payload (or grasping force) of the robotic hands and robotic arms with different drive methods. The results showed that the tendon drive system is easier to achieve light weight due to its simple structure, while the gear drive system can achieve a larger torque ratio, which results in a larger output torque. Further, the weight of the actuator accounts for a larger proportion of the total weight, and a reasonable external placement of the actuator is also beneficial to achieve light weight.
... movements are achieved by the coupled motion of two motors, where the supination-pronation axis is actuated when the motors rotate in the same direction, while the ulnar-radial deviation axis is actuated when the motors rotate in opposite direction. Controssi et al. [11] presented a prosthetic hand including a 2 DOF wrist, which is a differential mechanism with bevel gears and actuated by tendons attached to actuators placed next to the elbow. Another differential gear mechanism-based prosthetic device is presented in [12], and it can perform both the movements of flexion-extension and pronation-supination. Similarly, Kyberd et al. [13] proposed a 2-DOF prosthetic wrist with a differential gear mechanism, in which the movements of flexion-extension and pronation-supination can be also obtained by the couple motion of two motors. ...
This paper presents a new three-degrees-of-freedom spherical parallel manipulator, which is designed to be used as a prosthetic wrist. The inverse position problem is solved and a closed form equation is obtained. Afterward, using the screw theory approach, the mobility analysis is performed to demonstrate that the proposed mechanism performs spherical motion. The velocity analysis is carried out by means of screw theory, and an input–output velocity equation is obtained. Furthermore, a preliminary virtual design of the mechanism is presented and the workspace and analytical static analysis is performed. Finally, a set of dynamic simulations are carried out to demonstrate the three movements (i.e., pronation–supination, flexion–extension, and ulnar–radial deviation) of the wrist, and the simulation results show that the proposed mechanism is capable of performing the full range of motion required for daily living and the required actuation torques are obtained for the future development.
... A gearing system is also used by Controzzi et al. [53] however in this case a set of three bevel gears [52] are implemented. In contrast to the previous design, this arrangement results in a two DOF thumb as opposed to just one DOF however this system relies on being fully actuated in addition to being a bulkier and more complex solution. ...
This thesis presents an underactuated, anthropomorphic robot hand that can be used as a myoelectric prosthesis. The hand is both affordable and of low complexity when compared to existing commercial models. The prosthesis consists of four tendon-driven fingers and a thumb that are manufactured using the concept of hybrid deposition manufacturing. A set of antagonistic, elastic bands was used to implement the passive extension of the fingers offering increased performance and durability when compared with torsional springs that are typically used in pin joint based designs. A selectively lockable whiffletree differential mechanism was implemented in order to facilitate the execution of independent finger motions and of various everyday life grasps using a single actuator. The efficiency
and the performance of the proposed prosthetic hand were experimentally validated. The experiments performed focused on the repeatability of finger motions, the force exertion characteristics of the hand and its grasping and dexterous manipulation capabilities1. The total cost of the proposed prosthetic hand is $400 USD and the total weight is 530 g.
... While this design places more mass distally, the compact design occupies less forearm volume, making it more suitable for amputees with distal amputations. A similar differential design is employed in the transradial prosthesis design of [65], though motors are placed within the forearm volume and a tendon drive is used to actuate the input bevel gears. In both of these cases, both motors may contribute to actuating the same DOF, potentially allowing for greater mechanical power input to each DOF, though only actuated one at a time. ...
... As active wrist prostheses are not often able to match the torque production capacity of the human wrist, differential mechanisms [64], [65] allowing synergistic actuation of a single DOF can result in higher torque production in a small package. The tradeoff between size and torque-production/robustness is the biggest challenge to address in these devices. ...
The human wrist contributes greatly to the mobility of the arm/hand system, empowering dexterity and manipulation capabilities. However, both robotic and prosthetic research communities tend to favor the study and development of end effectors / terminal devices (hands, grippers etc.) over wrists. Wrists can improve manipulation capabilities, as they can orient the end effector of a system without imparting significant translational motion. In this paper, we review the current state of the art of wrist devices, ranging from passive wrist prostheses to actuated robotic wrist devices. We focus on the mechanical design and kinematic arrangements of said devices and provide specifications when available.
... Many prosthetic hands and robotic grippers have been designed by using tendon-driven actuators (19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). To demonstrate the capabilities of our EPTs, we used them to fabricate a six-DOF tendon-driven prosthetic hand that displays an advantageous combination of gripping speed and strength at a low cost. ...
The force, speed, dexterity, and compact size required of prosthetic hands present extreme design challenges for engineers. Current prosthetics rely on high-quality motors to achieve adequate precision, force, and speed in a small enough form factor with the trade-off of high cost. We present a simple, compact, and cost-effective continuously variable transmission produced via projection stereolithography. Our transmission, which we call an elastomeric passive transmission (EPT), is a polyurethane composite cylinder that autonomously adjusts its radius based on the tension in a wire spooled around it. We integrated six of these EPTs into a three-dimensionally printed soft prosthetic hand with six active degrees of freedom. Our EPTs provided the prosthetic hand with about three times increase in grip force without compromising flexion speed. This increased performance leads to finger closing speeds of ~0.5 seconds (average radial velocity, ~180 degrees second ⁻¹ ) and maximum fingertip forces of ~32 newtons per finger.
... El adormecimiento y la debilidad en las manos suele surgir debido a daño o enfermedad en los nervios. De la anatomía de la mano se destacan el flexor y el extensor largo común de los dedos y los extensores y flexores del dedo pulgar, los cuales intervienen directamente en el movimiento de las falanges distales [1,2]. Entre las causas más comunes de adormecimiento y debilidad en manos están las neuropatías, neuropatías diabéticas, neuropatías alcohólicas, artritis reumatoide, distrofia muscular, síndrome de túnel del carpo, entre otras causas [3]. ...
El adormecimiento y debilidad en las manos son padecimientos perjudiciales para la salud que son tratados por especialistas en esta área. La medición de cambios en la fuerza constituye información importante para asistir terapias de rehabilitación. En este trabajo se diseñó un dispositivo electrónico que mide simultáneamente la fuerza de las cinco falanges distales de la mano, para ser empleado como apoyo en fisioterapia. Para ello se utilizaron sensores resistivos de fuerza, se diseñó una interfaz de visualización y un teclado táctil capacitivo. Se obtuvo un dispositivo que permite medir la fuerza ejercida por las cinco falanges distales de manera simultánea o selectiva en uno o más dedos de la mano, en tiempo real de acuerdo con el interés del especialista y proporciona para cada falange de la mano tres indicadores de desempeño: la fuerza promedio, la fuerza máxima y el déficit a partir del test de prensión mantenida.
... In [8] a three finger single actuator hand design is presented. In [9] a tendon-driven dexterous hand was developed. Much like in humans, the actuators(motors) were mounted in the forearm rather than the hand. ...
Developments in rapid prototyping using 3D printing technology has played a major role in this change. However, despite the reduced cost, the objective of a prosthesis- that of replacing a lost limb remains incomplete. The natural feedback control humans possess by virtue of their tactile sensors is not achieved even in these new prostheses. Thus, this project aims to extend the idea of low cost 3D printed prosthesis as well as add a feedback functionality to it, thus enabling more intuitive control for amputees. The idea stems from the fact that humans inherently learn to adapt to any type of feedback over time- quite naturally. Thus adding sensing and feedback functions to already available designs or new ones would enable a prosthesis to feel more like a part of the person's body. To provide for this versatility, the proposed feedback system is made independent from the designed soft prosthesis i.e it is a standalone subsystem. Thus, it can not only work with the designed hand, but also any other hand, even industrial with no or minor modifications in shape. The hand design principles of passive compliance and underactuation are validated for their feasibility of use, considering that they provide numerous advantages over conventional rigid and fully actuated systems. To account for the difficulty in integrating an invasive feedback mechanism with the biological control system, a non-invasive system is designed and fabricated.
Thus, the aim is to solve two real world problems- prosthetic "acceptance" into the human system and industrial grasping with one elegant technological implementation.
