مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

طراحی و پیاده‌سازی کنترلر یاری‌گر پسخور خروجی فازی برای یک ربات اسکلت خارجی زانو با عملگر الاستیک سری

نوع مقاله : پژوهشی اصیل

نویسندگان
دانشگاه صنعتی شاهرود
چکیده
استفاده از عملگرهای الاستیک سری در ربات­های اسکلت خارجی باعث افزایش سطح راحتی در کاربران شده است. در این مقاله برای یک ربات اسکلت خارجی زانو که مجهز به یک عملگر الاستیک سری است، کنترلری ارائه و پیاده­سازی شده است تا افراد دارای ضعف عضلانی بتوانند با استفاده از این ربات حرکات خود را بازیابی نمایند. هدف اصلی کنترلر ارائه شده اصلاح پاسخ دینامیکی سیستم کوپل انسان-ربات می­باشد. به عبارت دیگر، کنترلر ارائه شده رابطه بین گشتاور اعمال شده خالص توسط ماهیچه انسان و برآیند حرکت زاویه­ای زانو را به گونه­ای تنظیم می­کند تا یاری­گری موثر ایجاد شود. در این روش که مستقل از قصد بیمار است، سنسورهای کمتری نسبت به سایر روش­ها استفاده شده است. همچنین، ضرایب کمتری برای تنظیم دارد که این ضرایب با استفاده از منطق فازی نوع صفر تاکاگی-سوگینو-کانگ محاسبه می­شوند. عملکرد ربات ساخته شده اس­یو­تی-نی­اگزو (SUT-KneeExo) و کنترلر ارائه شده، بر روی یک فرد ارزیابی شده است. نتایج شبیه­سازی و ارزیابی عملی نشان می­دهد ربات اسکلت خارجی به خوبی توانسته است دامنه سیگنال­های الکترومایوگرافی را کاهش دهد که به معنی یاری­رسانی در حین حرکت است. همچنین، مقایسه الگوریتم ارائه شده با حالت­های غیریاری شده، کنترل یاری­گر بر مبنای شکل­دهی انتگرال ادمیتانس و کنترل یاری­گر فیدبک خروجی نشان می­دهد که الگوریتم ارائه شده عملکرد بهتری دارد. به عبارت دیگر، در الگوریتم ارائه شده دامنه ادمیتانس انتگرالی بیشتر و اختلاف فاز کمتر شده است.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Design and implementation of a fuzzy output feedback assistive controller for a series-elastic-actuator-driven knee exoskeleton

نویسندگان English

Mona Sadat Ashrafi
Mostafa Nazari
Naserodin Sepehry
Masoud Mahdizadeh Rokhi
Parsa Samimi
Matin Attarchi
Shahrood University of Technology
چکیده English

The series elastic actuators make more comfort in the use of assistive exoskeletons. In this paper, an assistive controller is designed for a series-elastic-actuator-driven knee exoskeleton to restore normative mobility of individuals with weak muscles. The main target of the proposed controller is to modify the dynamics performance of the coupled human-exoskeleton system. In other words, the proposed controller modifies the relationship between the net muscle torque exerted by the human and the resulting angular motion. There are fewer sensors in the proposed intent-independent method relative to other methods. Moreover, there are less controller coefficients to regulate where these coefficients are extracted from a type zero Takagi-Sugeno-Kang fuzzy system. The performance of the controller is evaluated by simulations and experiments. The amplitude of the EMG signals decreased in a healthy person worn the SUT-KneeExo. Moreover, the proposed algorithm has a better performance in comparison with integral admittance shaping mothed and output feedback assistive controller. In other words, the amplitude of the integral admittance is more and the phase lag is less than other methods.

کلیدواژه‌ها English

Exoskeleton Robot
Fuzzy output feedback control method
Assistive control
Integral admittance
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