40 research outputs found
Powered exoskeleton for trunk assistance in industrial tasks
L'abstract è presente nell'allegato / the abstract is in the attachmen
Comparison of IMU set-ups for the estimation of gait spatio-temporal parameters in an elderly population
The increasing average age emphasizes the importance of gait analysis in elderly populations. Inertial Measurement Units (IMUs) represent a suitable wearable technology for the characterization of gait by estimating spatio-temporal parameters (STPs). However, the location of inertial sensors on the human body and the associated algorithms for the estimation of gait STPs play a fundamental role and are still open challenges. Accordingly, the aim of this work was to compare three IMUs set-ups (trunk, shanks, and ankles) and correspondent algorithms to a gold standard optoelectronic system for the estimation of gait STPs in a healthy elderly population. In total, 14 healthy elderly subjects walked barefoot at three different speeds. Gait parameters were assessed for each IMUs set-up and compared to those estimated with the gold standard. A statistical analysis based on Pearson correlation, Root Mean Square Error and Bland Altman plots was conducted to evaluate the accuracy of IMUs. Even though all tested set-ups produced accurate results, the IMU on the trunk performed better in terms of correlation (R ≥ 0.8), RMSE (0.01-0.06 s for temporal parameters, 0.03-0.04 for the limp index), and level of agreement (-0.01 s ≤ mean error ≤ 0.01 s, -0.02 s ≤ standard deviation error ≤ 0.02 s), also allowing simpler preparation of subjects and minor encumbrance during gait. From the promising results, a similar experiment might be conducted in pathological populations in the attempt to verify the accuracy of IMUs set-ups and algorithms also in non-physiological patterns
Il settore SE delle Terme Centrali: da quartiere residenziale a pars publica
Since 2001, the archaeological excavation of the University of Milan has been taking place in the so-called “E Area”, in the central area of the ancient Nora. This area shows a complex stratigraphic sequence with public buildings (the most important is the so-called Central Baths) and private houses. After the first analysis, the late roman city (after 450 AD) has been discovered: many houses (domus) dated at II-III century AD, with polychrome marbles, and big publics buildings with decorated floor have been individuated. Since 2008, the excavations have been taking place in the complex of the Central Baths, focusing in particular on the public accesses of the Severian Baths, analyzing also the previous phases characterized by a private use of the complex.Lo scavo dell’Università di Milano interessa dal 2001 l’area E, corrispondente al quartiere centrale della città di Nora. L’area presenta una complessa stratificazione insediativa connotata da edifici a carattere pubblico, di cui il più significativo è il complesso delle c.d. Terme Centrali, e altri a connotazione privata di vario tenore. Le prime indagini hanno consentito la ricostruzione della città tardoantica (post 450 d.C.), nonché la definizione della fase in cui alcune domus di II-III secolo, ricche di pavimentazioni in mosaici policromi, vengono ad accostarsi a grandi edifici pubblici parimenti decorati. L’attività archeologica degli ultimi cinque anni si è concentrata invece sul complesso delle Terme Centrali, dove si sono cercati gli accessi al complesso termale di età severiana e si sono analizzate le fasi precedenti (e di natura privata) alle terme
Gait Phases Detection in Elderly using Trunk-MIMU System
The increasing interest towards wearable Magnetic Inertial Measurement Units (MIMUs) for gait analysis is justified by their low invasiveness, confirmed repeatability and complete independence from laboratory constraints. However, some crucial doubts about the identification of a suitable sensor set-up and algorithm in different gait conditions and populations still exist. In this context, the principal aim of the present study was to investigate the effect of different walking conditions on the accuracy of gait phases detection with a trunk-MIMU system. Eleven healthy elderly subjects performed gait trials in four different walking conditions (fast speed, normal speed, slow speed and normal speed with dual-task). A stereophotogrammetric system was adopted as gold standard. The accuracy of the estimation of stance and swing phases was evaluated from the comparison of trunk-MIMU to the stereophotogrammetric system. Mean error values smaller than 0.03 s confirmed the accuracy of the tru nk-MIMU algorithm for an elderly population. Consequently, trunk-MIMU system can be considered suitable for the characterization of gait phases in elderly subjects regardless of walking conditions
Standardized Biomechanical Investigation of Posture and Gait in Pisa Syndrome Disease
Pisa syndrome is one of the possible postural deformities associated with Parkinson's disease and it is clinically defined as a sustained lateral bending of the trunk. Some previous studies proposed clinical and biomechanical investigation to understand the pathophysiological mechanisms that occur, mainly focusing on EMG patterns and clinics. The current research deals with the assessment of a standardized biomechanical analysis to investigate the Pisa syndrome postural effects. Eight patients participated in the experimental test. Both static posture and gait trials were performed. An optoelectronic system and two force plates were used for data acquisition, while a custom multi-segments kinematic model of the human spine was used to evaluate the 3D angles. All subjects showed an important flexion of the trunk superior segment with respect to the inferior one, with a strong variability among patients (range values between 4.3 degrees and 41.0 degrees). Kinematics, ground reaction forces and spatio-temporal parameters are influenced by the asymmetrical trunk posture. Moreover, different proprioception, compensation and abilities of correction were depicted among subjects. Considering the forces exchanged by the feet with the floor during standing, results highlighted a significant asymmetry (p-value = 0.02) between the omo and contralateral side in a normal static posture, with greater load distribution on the same side of lateral deviation. When asked to self-correct the posture, all patients demonstrated a reduction of asymmetry, but without stressing any statistical significance. All these aspects might be crucial for the definition of a PS patients' classification and for the assessment of the efficacy of treatments and rehabilitation