Biomedical subjects

M C Carrozza

Publications and source records attributed to M C Carrozza.

5 recordsLinked to original sources

PubMed2006

Design of a cybernetic hand for perception and action.

Strong motivation for developing new prosthetic hand devices is provided by the fact that low functionality and controllability-in addition to poor cosmetic appearance-are the most important reasons why amputees do not regularly use their prosthetic hands. This paper presents the design of the CyberHand, a cybernetic anthropomorphic hand intended to provide amputees with functional hand replacement. Its design was bio-inspired in terms of its modular architecture, its physical appearance, kinematics, sensorization, and actuation, and its multilevel control system. Its underactuated mechanisms allow separate control of each digit as well as thumb-finger opposition and, accordingly, can generate a multitude of grasps. Its sensory system was designed to provide proprioceptive information as well as to emulate fundamental functional properties of human tactile mechanoreceptors of specific importance for grasp-and-hold tasks. The CyberHand control system presumes just a few efferent and afferent channels and was divided in two main layers: a high-level control that interprets the user's intention (grasp selection and required force level) and can provide pertinent sensory feedback and a low-level control responsible for actuating specific grasps and applying the desired total force by taking advantage of the intelligent mechanics. The grasps made available by the high-level controller include those fundamental for activities of daily living: cylindrical, spherical, tridigital (tripod), and lateral grasps. The modular and flexible design of the CyberHand makes it suitable for incremental development of sensorization, interfacing, and control strategies and, as such, it will be a useful tool not only for clinical research but also for addressing neuroscientific hypotheses regarding sensorimotor control.

Algorithms↗

PubMed2002

Control of multifunctional prosthetic hands by processing the electromyographic signal.

The human hand is a complex system, with a large number of degrees of freedom (DoFs), sensors embedded in its structure, actuators and tendons, and a complex hierarchical control. Despite this complexity, the efforts required to the user to carry out the different movements is quite small (albeit after an appropriate and lengthy training). On the contray, prosthetic hands are just a pale replication of the natural hand, with significantly reduced grasping capabilities and no sensory information delivered back to the user. Several attempts have been carried out to develop multifunctional prosthetic devices controlled by electromyographic (EMG) signals (myoelectric hands), harness (kinematic hands), dimensional changes in residual muscles, and so forth, but none ofthese methods permits the "natural" control of more than two DoFs. This article presents a review of the traditional methods used to control artificial hands by means of EMG signal, in both the clinical and research contexts, and introduces what could be the future developments in the control strategy of these devices.

Algorithms↗

PubMed2002

A two DoF finger for a biomechatronic artificial hand.

Current prosthetic hands are basically simple grippers with one or two degrees of freedom, which barely restore the capability of the thumb-index pinch. Although most amputees consider this performance as acceptable for usual tasks, there is ample room for improvement by exploiting recent progresses in mechatronics design and technology. We are developing a novel prosthetic hand featured by multiple degrees of freedom, tactile sensing capabilities, and distributed control. Our main goal is to pursue an integrated design approach in order to fulfill critical requirements such as cosmetics, controllability, low weight, low energy consumption and noiselessness. This approach can be synthesized by the definition "biomechatronic design", which means developing mechatronic systems inspired by living beings and able to work harmoniously with them. This paper describes the first implementation of one single finger of a future biomechatronic hand. The finger has a modular design, which allows to obtain hands with different degrees of freedom and grasping capabilities. Current developments include the implementation of a hand comprising three fingers (opposing thumb, index and middle) and an embedded controller.

Artificial Limbs↗

PubMed2000

A novel mechatronic tool for computer-assisted arthroscopy.

This paper describes a novel mechatronic tool for arthroscopy, which is at the same time a smart tool for traditional arthroscopy and the main component of a system for computer-assisted arthroscopy. The mechatronic arthroscope has a cable-actuated servomotor-driven multi-joint mechanical structure, is equipped with a position sensor measuring the orientation of the tip and with a force sensor detecting possible contact with delicate tissues in the knee, and incorporates an embedded microcontroller for sensor signal processing, motor driving and interfacing with the surgeon and/or the system control unit. When used manually, the mechatronic arthroscope enhances the surgeon's capabilities by enabling him/her to easily control tip motion and to prevent undesired contacts. When the tool is integrated in a complete system for computer-assisted arthroscopy, the trajectory of the arthroscope is reconstructed in real time by an optical tracking system using infrared emitters located in the handle, providing advantages in terms of improved intervention accuracy. The computer-assisted arthroscopy system comprises an image processing module for segmentation and three-dimensional reconstruction of preoperative computer tomography or magnetic resonance images, a registration module for measuring the position of the knee joint, tracking the trajectory of the operating tools, and matching preoperative and intra-operative images, and a human-machine interface that displays the enhanced reality scenario and data from the mechatronic arthroscope in a friendly and intuitive manner. By integrating preoperative and intra-operative images and information provided by the mechatronic arthroscope, the system allows virtual navigation in the knee joint during the planning phase and computer guidance by augmented reality during the intervention. This paper describes in detail the characteristics of the mechatronic arthroscope and of the system for computer-assisted arthroscopy and discusses experimental results obtained with a preliminary version of the tool and of the system.

Arthroscopes↗

PubMed1999

Development and in vitro testing of a miniature robotic system for computer-assisted colonoscopy.

In this article we present a new concept for computer-assisted colonoscopy based on a miniature robot capable of propelling itself semiautonomously along the colon. The miniature robot is designed to perform the same functions as current colonoscopy systems-i.e., visualization and tissue sampling for biopsy-and exploits an innovative inchworm-like locomotion principle based on adhering to the colon wall by vacuum suction. The miniature robot is connected by a thin and flexible umbilical cable to an external control unit; this unit provides pneumatic actuation signals in the appropriate sequence to the miniature robot, and information on the robot's functioning to the endoscopist, who can either teleoperate or directly supervise its operation. A prototype colonoscopy system using this robot has been fabricated and tested in vitro, with promising results. The proposed concept has strong potential for further development, since miniaturization and functional integration of instrumentation and tools, together with computer assistance, not only make colonoscopy more acceptable, but can also open up a wide range of new applications in endoluminal diagnosis, therapy, and surgery.

Animals↗