176 research outputs found

    Analysis of the energy consumption of a rotary harrow

    Get PDF
    This paper shows the development and study of a FEM model of a rotary harrow. A proper use of a rotary harrow depends on its geometry and on the working parameters, such as: drag speed and angular speed. The aim of this work is to develop a rotary harrow model in the ANSYS environment in order to analyze and to optimize its geometric parameters. The model, validated through comparison with some experimental data, was then used to analyze the forces exchanged between the tines and the soil as a function of the drag speed, the angular speed and the working depth. Different tine orientations and three different types of terrain were considere

    Soft Pneumatic Actuators for Rehabilitation

    Get PDF
    Pneumatic artificial muscles are pneumatic devices with practical and various applications as common actuators. They, as human muscles, work in agonistic-antagonistic way, giving a traction force only when supplied by compressed air. The state of the art of soft pneumatic actuators is here analyzed: different models of pneumatic muscles are considered and evolution lines are presented. Then, the use of Pneumatic Muscles (PAM) in rehabilitation apparatus is described and the general characteristics required in different applications are considered, analyzing the use of proper soft actuators with various technical properties. Therefore, research activity carried out in the Department of Mechanical and Aerospace Engineering in the field of soft and textile actuators is presented here. In particular, pneumatic textile muscles useful for active suits design are described. These components are made of a tubular structure, with an inner layer of latex coated with a deformable outer fabric sewn along the edge. In order to increase pneumatic muscles forces and contractions Braided Pneumatic Muscles are studied. In this paper, new prototypes are presented, based on a fabric construction and various kinds of geometry. Pressure-force-deformation tests results are carried out and analyzed. These actuators are useful for rehabilitation applications. In order to reproduce the whole upper limb movements, new kind of soft actuators are studied, based on the same principle of planar membranes deformation. As an example, the bellows muscle model and worm muscle model are developed and described. In both cases, wide deformations are expected. Another issue for soft actuators is the pressure therapy. Some textile sleeve prototypes developed for massage therapy on patients suffering of lymph edema are analyzed. Different types of fabric and assembly techniques have been tested. In general, these Pressure Soft Actuators are useful for upper/lower limbs treatments, according to medical requirements. In particular devices useful for arms massage treatments are considered. Finally some applications are considered

    An Active Exoskeleton Called P.I.G.R.O. Designed for Unloaded Robotic Neurorehabilitation Training

    Get PDF
    The development of innovative robotic devices allows the design of exoskeletons for robotic neurorehabilitation training. This paper presents the active exoskeleton called pneumatic interactive gait rehabilitation orthosis (P.I.G.R.O.), developed by the authors. The main innovative characteristic of this prototype is its design for fully unloaded robotic neurorehabilitation training, specific for brain-injured patients. It has six degrees of freedom (DOF) in the sagittal plane, an active ankle joint (removable if it is required); a wide range of anthropometric regulations, both for men and for women; a useful human machine interface (HMI); and an innovative harness system for the patient for the unloaded training. It is realized using light and strong materials, and it is electropneumatically controlled. In particular the authors also studied and defined some innovative input control curves useful for the unloaded training. In this paper, the main characteristics and innovations of P.I.G.R.O. are presented

    PRELIMINARY STRUCTURAL ANALYSIS OF AN ACTIVE EXOSKELETON FOR ROBOTIC NEURO-REHABILITATION

    Get PDF
    In this paper the exoskeleton P.I.G.R.O. (Pneumatic Interactive Gait Rehabilitation Orthosis), developed in the Department of Mechanical and Aerospace Engineering (DIMEAS) Politecnico di Torino with the important co-operation with doctors, is presented. It was preliminary designed for a completely unloaded walking gait cycle in order to treat the first steps of the neurorehabilitation trainings. An initial FEM evaluation of P.I.G.R.O. structure is here presented. It underlines a lot of important aspects and techniques to analyse the structural characteristics of P.I.G.R.O. legs rigid parts using a commercial software but analysing both the actions of the pneumatic actuators and of the patients muscles and/or movements. The results obtained are good and allow to verify the P.I.G.R.O. legs structure and to establish a procedure to study its characteristics also with the presence of the patien

    A Combined Robotic and Cognitive Training for Locomotor Rehabilitation: Evidences of Cerebral Functional Reorganization in Two Chronic Traumatic Brain Injured Patients

    Get PDF
    It has been demonstrated that automated locomotor training can improve walking capabilities in spinal cord-injured subjects but its effectiveness on brain damaged patients has not been well established. A possible explanation of the discordant results on the efficacy of robotic training in patients with cerebral lesions could be that these patients, besides stimulation of physiological motor patterns through passive leg movements, also need to train the cognitive aspects of motor control. Indeed, another way to stimulate cerebral motor areas in paretic patients is to use the cognitive function of motor imagery. A promising possibility is thus to combine sensorimotor training with the use of motor imagery. The aim of this paper is to assess changes in brain activations after a combined sensorimotor and cognitive training for gait rehabilitation. The protocol consisted of the integrated use of a robotic gait orthosis prototype with locomotor imagery tasks. Assessment was conducted on two patients with chronic traumatic brain injury and major gait impairments, using functional magnetic resonance imaging. Physiatric functional scales were used to assess clinical outcomes. Results showed greater activation post-training in the sensorimotor and supplementary motor cortices, as well as enhanced functional connectivity within the motor network. Improvements in balance and, to a lesser extent, in gait outcomes were also found

    Bra.Di.P.O. and P.I.G.R.O.: Innovative Devices for Motor Learning Programs

    Get PDF
    Two mechatronics prototypes, useful for robotic neurotreatments and new clinical trainings, are here presented. P.I.G.R.O. (pneumatic interactive gait rehabilitation orthosis) is an active exoskeleton with an electropneumatic control. It imposes movements on lower limbs in order to produce in the patient’s brain proper motor cortex activation. Bra.Di.P.O. (brain discovery pneumatic orthosis) is an MR-compatible device, designed to improve fMRI (functional magnetic resonance imaging) analysis. The two devices are presented together because both are involved in the study of new robotic treatments of patients affected by ictus or brain stroke or in some motor learning experimental investigations carried out on healthy subjects
    corecore