Stability Augmentation of a Semi-Autonomous Wheelchair

Download

index.pdf

Date

2004

Author

Ayık, H. Müjde

Metadata

Show full item record

Item Usage Stats

227
views

108
downloads

In this thesis, the dynamic modeling of a wheelchair-human system is performed, and the effects of steering action and sudden slope changes along the path on the system stability are analyzed for different road and driving conditions. For the cases where the wheelchair system is unstable three methods are proposed for stability augmentation. This study is performed to improve the stability of the wheelchair system under varying road conditions so as to increase the limit of independency for wheelchair users and enhance their life quality. Two separate mathematical models are obtained for the wheelchair driven on constant sloped and changing sloped roads. Matlab Simulink models are constructed with the obtained mathematical models and control structure. The stability of the system is analyzed by case studies and it is seen that the system is unstable in some of these cases. Three methods are used for enhancement of the stability. One is the speed reduction via joystick module during steep turns, by which the speed of the wheelchair is reduced automatically for a safe steering, but the wheelchair follows the desired course. The second method is the use of a shape filter in order to obtain a less jerky response for the speed. As a final method, the center of mass of the wheelchair-human system is shifted gently in a controlled manner to the side where the reaction force on the wheels decreases.

Subject Keywords

Research.

URI

http://etd.lib.metu.edu.tr/upload/12605377/index.pdf
https://hdl.handle.net/11511/14412

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Steering of redundant robotic manipulators and spacecraft integrated power and attitude control-control moment gyroscopes Altay, Alkan; Tekinalp, Ozan; Department of Aerospace Engineering (2005) In this thesis, recently developed Blended Inverse (B-inverse) steering law is applied to two different redundant actuator systems. First, repeatability of Binverse is demonstrated on a redundant robotic manipulator. Its singularity avoidance and singularity transition performance is also demonstrated on the same actuator system. It is shown that B-inverse steering law provides singularity avoidance, singularity transition and repeatability. Second, its effectiveness is demonstrated for an Integrated Power ...
Design of smart controllers for hybrid electric vehicles Özen, Ekin; Dölen, Melik; Department of Mechanical Engineering (2005) This thesis focuses on the feasibility of designing a commercial hybrid electric vehicle (HEV). In this work, relevant system models are developed for the vehicle including powertrain, braking system, electrical machines and battery. Based on these models ten different HEV configurations are assembled for detailed assessment of fuel consumption. This thesis also proposes a smart power management strategy which could be applied to any kind of HEV configuration. The suggested expert system deals with the exte...
Extraction of auditory evoked potentials from ongoing eeg Aydın, Serap; Gençer, Nevzat Güneri; Department of Electrical and Electronics Engineering (2005) In estimating auditory Evoked Potentials (EPs) from ongoing EEG the number of sweeps should be reduced to decrease the experimental time and to increase the reliability of diagnosis. The rst goal of this study is to demon- strate the use of basic estimation techniques in extracting auditory EPs (AEPs) from small number of sweeps relative to ensemble averaging (EA). For this purpose, three groups of basic estimation techniques are compared to the traditional EA with respect to the signal-to-noise ratio(SNR) ...
Implementation of a hazard rating system to the cut slopes along Kizilcahamam-Gerede segment of d750 highway Çiçek, Ceren; Doyuran, Vedat; Department of Geological Engineering (2009) The purpose of this study is to implement a rock fall hazard rating system to the cut slopes along Kızılcahamam-Gerede segment of D750 (Ankara-İstanbul) Highway. The rating system developed by the Tennessee Department of Transportation was assessed for thirty six cut slopes which were selected based on a reconnaissance survey along D750 highway, between Kurtboğazı Dam (50 km northwest of Ankara) and Aktaş village (15 km to Gerede town of Bolu province). The stages of the investigation consist of project con...
Assessing impacts of the European framework programme on Turkish participants: a case study on FP6 IST priorty Metin, Hüseyin; Çilingir, Canan; Erdil, Erkan; Department of Industrial Engineering (2010) This thesis aims to assess impacts of European Framework Programme for Research and Technological Development (FP) on Turkish participants, focusing on Sixth Framework Programme (FP6) Information Society Technologies (IST) priority. A two-sided approach was employed while assessing impacts. First, DELPHI method was used to quantify and prioritise expectations of the decision makers in key stakeholders; second, a survey was designed to measure additionalities and the level of achievements of program particip...

Citation Formats

H. M. Ayık, “Stability Augmentation of a Semi-Autonomous Wheelchair,” M.S. - Master of Science, Middle East Technical University, 2004.