Design of a Reconfiguration Mechanism for an Electric Stair-Climbing Wheelchair

Author(s):  
Giuseppe Quaglia ◽  
Walter Franco ◽  
Matteo Nisi

In this paper is described a new solution for a stair-climbing wheelchair: a device that allows disabled people to autonomously overcome architectural barriers. The paper presents the evolution of a project introduced in previous works. The aim is to obtain a wheelchair able to move both in structured and unstructured environments and overcome single steps or an entire staircase. The innovative aspect of this work is the introduction of a hybrid solution, with a locomotion system based on wheels and an idle track for the vehicle stability. The locomotion group permits to overcome obstacles through an original architecture based on an epicycloidal transmission. The control logic manages the motors that drive independently the two degrees of freedom of the transmission and allows to switch from an advancing mode to a climbing one. The wheelchair must be able to move in different environments, such as flat ground or stairs, which require different specifications, sometimes in contrast. For this reason the main part of the work regards the design of a reconfiguration mechanism able to prepare the wheelchair for different working conditions. First of all the relative positions between the elements that compose the wheelchair structure in different configuration are studied in order to optimize the performances especially in terms of regularity. Then several possible solutions for the reconfiguration mechanism are presented and qualitatively evaluated, in order to choose the one that satisfy the design specifications.

Author(s):  
Giuseppe Quaglia ◽  
Matteo Nisi ◽  
Walter Franco

The presence of architectural barriers in public or private buildings represents an important limit for the mobility of wheelchair users. Although norms promote barriers removal, often a complete accessibility cannot be guaranteed due to economic or technical reasons. In such cases, it is necessary to provide disable people with devices able to autonomously climb architectural barriers or obstacles. Referring to user needs, some requirements for the wheelchair can be defined. Firstly, the user must use it autonomously. Secondly, it should be easy to use, simple in the mechanical and control systems and with limited weight, dimensions, and cost. Finally, also the appearance of the wheelchair must be adequate to guarantee the user acceptability. In literature, several solutions of stair-climbing wheelchair are proposed. However, none of these completely satisfies the identified requirements. In this paper, the Wheelchair.q05, an innovative concept for a stair-climbing wheelchair, is presented. This idea has been developed through several years of researches and functional designs. In detail, this work presents the final design for a constructive and real scale prototype. The proposed wheelchair, thanks to a smart and hybrid locomotion system, is able to move on flat ground and to climb stairs and sidewalks. A triangular shaped frame with a wheel on each corner, connected through an internal epicyclical transmission system, constitutes the locomotion unit. This system provides the traction both for flat ground and stair motion. Moreover, the wheelchair has an idle track that represents the rear contact point during stair-climbing and guarantees only a stable and regular climbing motion. The wheelchair structure is thus constituted by the following functional elements: two locomotion units, the track, the seat and a couple of pivoting wheels connected to floating arms that represents the rear support during flat ground motion and during sidewalks overcoming. Through a kinematic synthesis, the optimal layout has been defined and the mechanisms that connect the functional elements with the frame have been designed. These mechanisms allow controlling the wheelchair reconfiguration that is necessary to adapt the vehicle to different working conditions. Moreover, attention has been paid to the user comfort. Thanks to the introduction of a mechanism that controls the seat orientation, the oscillations generated by the motion on stair are compensated and a regular trajectory is guaranteed for the user center of mass.


Machines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 10
Author(s):  
Luca Bruzzone ◽  
Mario Baggetta ◽  
Shahab E. Nodehi ◽  
Pietro Bilancia ◽  
Pietro Fanghella

This paper presents the conceptual and functional design of a novel hybrid leg-wheel-track ground mobile robot for surveillance and inspection, named WheTLHLoc (Wheel-Track-Leg Hybrid Locomotion). The aim of the work is the development of a general-purpose platform capable of combining tracked locomotion on irregular and yielding terrains, wheeled locomotion with high energy efficiency on flat and compact grounds, and stair climbing/descent ability. The architecture of the hybrid locomotion system is firstly outlined, then the validation of its stair climbing maneuver capabilities by means of multibody simulation is presented. The embodiment design and the internal mechanical layout are then discussed.


2021 ◽  
pp. 026858092199450
Author(s):  
Nicola Maggini ◽  
Tom Montgomery ◽  
Simone Baglioni

Against the background of crisis and cuts, citizens can express solidarity with groups in various ways. Using novel survey data this article explores the attitudes and behaviours of citizens in their expressions of solidarity with disabled people and in doing so illuminates the differences and similarities across two European contexts: Italy and the UK. The findings reveal pools of solidarity with disabled people across both countries that have on the one hand similar foundations such as the social embeddedness and social trust of citizens, while on the other hand contain some differences, such as the more direct and active nature of solidarity in Italy compared to the UK and the role of religiosity as an important determinant, particularly in Italy. Across both countries the role of ‘deservingness’ was key to understanding solidarity, and the study’s conclusions raise questions about a solidarity embedded by a degree of paternalism and even religious piety.


Author(s):  
Farong Zhu ◽  
Robert G. Parker

One-way clutches are frequently used in the serpentine belt accessory drives of automobiles and heavy vehicles. The clutch plays a role similar to a vibration absorber in order to reduce belt/pulley vibration and noise and increase belt life. This paper analyzes a two-pulley system where the driven pulley has a one-way clutch between the pulley and accessory shaft that engages only for positive relative displacement between these components. The belt is modeled with linear springs that transmit torque from the driving pulley to the accessory pulley. The one-way clutch is modeled as a piecewise linear spring with discontinuous stiffness that separates the driven pulley into two degrees of freedom (DOF). The harmonic balance method (HBM) combined with arc-length continuation is employed to illustrate the nonlinear dynamic behavior of the one-way clutch. HBM with arc-length continuation yields the stable and unstable periodic solutions for given parameters. These solutions are examined across a range of excitation frequencies. The results are confirmed by numerical integration and the widely used bifurcation software AUTO. At the first primary resonance, most of the responses are aperiodic, including quasiperiodic and chaotic solutions. At the second primary resonance, the peak bends to the left with classical softening nonlinearity because clutch disengagement decouples the pulley and the accessory over portions of the response period. The dependence on system parameters such as clutch stiffness, excitation amplitude, and inertia ratio between the pulley and accessory is studied to characterize the nonlinear dynamics across a range of conditions.


Author(s):  
Payman Joudzadeh ◽  
Alireza Hadi ◽  
Bahram Tarvirdizadeh ◽  
Danial Borooghani ◽  
Khalil Alipour

Purpose This paper aims to deal with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending. Design/methodology/approach For this purpose, a novel design of a mixture of motors and cables has been proposed for users to wear them easily and show the application of the system in stair climbing. Findings One of the prominences of this study is the provided robot design where four joints are actuated with only two motors; each motor actuates either the knees or ankles. Another advantage of the designed system is that with motors placed in a backpack, the knee braces can be worn under clothes to be concealed. Finally, the system performance is evaluated using electromyography (EMG) signals showing 28 per cent reduction in energy consumption of related muscles. Originality/value This investigation deals with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.


2013 ◽  
Vol 16 (2) ◽  
pp. 5-12
Author(s):  
Nghin Van Dang ◽  
Co Pham ◽  
Thong Hoang Pham ◽  
Phuc Dang Ho

This paper presents developing Alber principle for machine supporting wheelchair in climbing stairs. The designed machine can support wheelchair and disabled people with total weight 80 kg climb up and down most of stairs and with speed 10-15 stairs per minute. Moving wheelchair and disabled people need assistant person who will hold handle and control the machine. The machine is designed with a simple structure, manufactured with low cost and simple controlling. Therefore the machine can be upgraded and manufactured in future.


Author(s):  
Raj Desai ◽  
Anirban Guha ◽  
Pasumarthy Seshu

Long duration automobile-induced vibration is the cause of many ailments to humans. Predicting and mitigating these vibrations through seat requires a good model of seated human body. A good model is the one that strikes the right balance between modelling difficulty and simulation results accuracy. Increasing the number of body parts which have been separately modelled and increasing the number of ways these parts are connected to each other increase the number of degrees of freedom of the entire model. A number of such models have been reported in the literature. These range from simple lumped parameter models with limited accuracy to advanced models with high computational cost. However, a systematic comparison of these models has not been reported till date. This work creates eight such models ranging from 8 to 26 degrees of freedom and tries to identify the model which strikes the right balance between modelling complexity and results accuracy. A comparison of the models’ prediction with experimental data published in the literature allows the identification of a 12 degree of freedom backrest supported model as optimum for modelling complexity and prediction accuracy.


2019 ◽  
Vol 272 ◽  
pp. 01024 ◽  
Author(s):  
Feng YU ◽  
Jun XIE

Eight degrees of freedom vehicle model was established. Using the method of fuzzy control, the ABS control algorithm was designed based on slip ratio. Simulation analysis was done at speed of 15m/s, 20m/s, 25m/s under turning braking. The results show that the vehicle braking performance and vehicle stability at middle or low speed was improved by using the ABS controller, but qualitative analysis shows that phenomenon of vehicle instability was appeared at high-speed conditions. The turning braking stability under ABS controller was judged quantificationally by the stability judging formula. The results show that the requirements of stability control could not meet with only Anti-lock Braking System.


2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Koun-Tem Sun ◽  
Kai-Lung Hsieh ◽  
Syuan-Rong Syu

This study proposes a home care system (HCS) based on a brain-computer interface (BCI) with a smartphone. The HCS provides daily help to motor-disabled people when a caregiver is not present. The aim of the study is two-fold: (1) to develop a BCI-based home care system to help end-users control their household appliances, and (2) to assess whether the architecture of the HCS is easy for motor-disabled people to use. A motion-strip is used to evoke event-related potentials (ERPs) in the brain of the user, and the system immediately processes these potentials to decode the user’s intentions. The system, then, translates these intentions into application commands and sends them via Bluetooth to the user’s smartphone to make an emergency call or to execute the corresponding app to emit an infrared (IR) signal to control a household appliance. Fifteen healthy and seven motor-disabled subjects (including the one with ALS) participated in the experiment. The average online accuracy was 81.8% and 78.1%, respectively. Using component N2P3 to discriminate targets from nontargets can increase the efficiency of the system. Results showed that the system allows end-users to use smartphone apps as long as they are using their brain waves. More important, only one electrode O1 is required to measure EEG signals, giving the system good practical usability. The HCS can, thus, improve the autonomy and self-reliance of its end-users.


2009 ◽  
Vol 24 (08n09) ◽  
pp. 1764-1776
Author(s):  
WELITON M. SOARES ◽  
THIERRY PASSERAT DE SILANS ◽  
MARCOS ORIÁ ◽  
MARTINE CHEVROLLIER

The dipolar interaction between neutral atoms and non-resonant surfaces results in attractive potentials.We describe here techniques to probe these interactions, particulary focussing in mechanisms to selectively prepare adsorption quantum states. The control of the external degrees of freedom of atoms very close to a surface allows one, in the one hand, to get values for the parameters of the potentials between neutral atoms and solid surfaces and, on the other hand, to develop schemes to explore matter behavior at low dimensionality. As an application for the 2D confined atomic matter-wave we consider Bloch oscillation for atoms in a periodic surface potential.


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