ﮐﻨﺘﺮل ﺗﻄﺒﯿﻘﯽ ﻋﺼﺒﯽ ﭘﺎﻧﮑﺮاس ﻣﺼﻨﻮﻋﯽ ﺑﺮاي ﺑﯿﻤﺎران دﯾﺎﺑﺖ ﻧﻮع ﯾﮏ ﺑﺎ در ﻧﻈﺮ ﮔﺮﻓﺘﻦ ﻣﺤﺪودﯾﺖ در ﻧﺮخ اﻧﺴﻮﻟﯿﻦ ﺗﺰرﯾﻘﯽ

Neural Adaptive Control of an Artificial Pancreas for People with Type 1 Diabetes Under Saturated Insulin Injection Rate

ﭼﮑﯿﺪه: ﮐﻨﺘﺮل ﻣﺘﻐﯿﺮﻫﺎي ﺣﯿﺎﺗﯽ در اﻓﺮاد ﺑﯿﻤﺎر ﮐﻪ ﺳﯿﺴﺘﻢ ﮐﻨﺘﺮل ﻃﺒﯿﻌﯽ آنﻫﺎ ﺑﻪ دﻻﯾﻠﯽ ﺑﺎ ﻣﺸﮑﻞ ﻣﻮاﺟﻪ ﺷﺪه، اﻣﺮي ﺿﺮوري اﺳﺖ. ﯾﮑﯽ از اﯾﻦ ﻣﺘﻐﯿﺮﻫﺎي ﺣﯿﺎﺗﯽ ﺳﻄﺢ ﮔﻠﻮﮐﺰ ﺧﻮن اﺳﺖ و ﻣﺘﺎﺳﻔﺎﻧﻪ در اﻓﺮادي ﮐﻪ دﭼﺎر ﺑﯿﻤﺎري دﯾﺎﺑﺖ )ﺑﯿﻤﺎري ﻗﻨﺪ ﺧﻮن( ﻫﺴﺘﻨﺪ ﺗﻨﻈﯿﻢ ﺳﻄﺢ ﮔﻠﻮﮐﺰ ﺧﻮن ﺑﻪدرﺳﺘﯽ ﺻﻮرت ﻧﻤﯽﮔﯿﺮد. در ﺟﻬﺖ ﺟﺒﺮان اﯾﻦ ﻓﻘﺪان، در ﺳﺎلﻫﺎي ﮔﺬﺷﺘﻪ ﺗﺤﻘﯿﻘﺎت و ﺗﻼشﻫﺎي ﻣﺘﻌﺪدي ﺟﻬﺖ ﺳﺎﺧﺖ و ﺑﻬﺒﻮد ﻋﻤﻠﮑﺮد ﭘﺎﻧﮑﺮاس ﻣﺼﻨﻮﻋﯽ ﺑﻪ ﺟﻬﺖ ﮐﻨﺘﺮل ﻗﻨﺪ ﺧﻮن اﻧﺠﺎم ﮔﺮﻓﺘﻪ اﺳﺖ. وﺟﻮد ﻋﻮاﻣﻠﯽ ﻣﺎﻧﻨﺪ ﻧﺎﻣﻌﯿﻨﯽﻫﺎي ﻣﺘﻌﺪد ﮐﻪ ﻧﺎﺷﯽ از ﺗﻔﺎوتﻫﺎي ﻓﯿﺰﯾﻮﻟﻮژﯾﮑﯽ در اﺷﺨﺎص، ﻓﻌﺎﻟﯿﺖﻫﺎي ﮔﻮﻧﺎﮔﻮن در ﻃﻮل روز، اﺛﺮﮔﺬاري ﺑﺎ ﺗﺎﺧﯿﺮ ﮐﺮﺑﻮﻫﯿﺪراتﻫﺎ در ﻣﯿﺰان ﻗﻨﺪ ﺧﻮن ﺑﺪن، اﺳﺘﺮس و ورزش، ﮐﻨﺘﺮل ﭘﺎﻧﮑﺮاس ﻣﺼﻨﻮﻋﯽ را ﺑﻪ ﻣﻮﺿﻮﻋﯽ ﭘﺮ ﭼﺎﻟﺶ ﺗﺒﺪﯾﻞ ﮐﺮده اﺳﺖ. اﻣﺎ ﯾﮑﯽ از ﭼﺎﻟﺶﻫﺎي ﻣﻬﻢ در اﯾﻦ ﺣﻮزه ﮐﻪ ﮐﻤﺘﺮ در ﺗﺎرﯾﺨﭽﻪ ﺑﻪ آن ﭘﺮداﺧﺘﻪ ﺷﺪه اﺳﺖ، وﺟﻮد ﻣﺤﺪودﯾﺖ در دز ﻣﺠﺎز ﺗﺰرﯾﻖ اﻧﺴﻮﻟﯿﻦ در ﭘﺎﻧﮑﺮاس ﻣﺼﻨﻮﻋﯽ ﺑﺮاي ﺑﯿﻤﺎران دﯾﺎﺑﺖ ﻧﻮع ﯾﮏ اﺳﺖ. از ﺳﻮﯾﯽ ﺗﺰرﯾﻖ دز ﺑﺎﻻ ﻣﯽﺗﻮاﻧﺪ ﻣﺸﮑﻼﺗﯽ ﻣﺎﻧﻨﺪ ﻫﺎﯾﭙﺮﮔﻠﯿﺴﻤﯽ را در ﺑﯿﻤﺎران ﺑﻪ وﺟﻮد آورد و از ﺳﻮي دﯾﮕﺮ ﺗﺰرﯾﻖ دز ﻣﻨﻔﯽ اﻧﺴﻮﻟﯿﻦ ﺑﯽﻣﻌﻨﺎ اﺳﺖ. در اﯾﻦ ﻣﻘﺎﻟﻪ ﭘﺲ از اﻧﺘﺨﺎب ﻣﺪل ﺑﺮﮔﻤﻦ و در ﻧﻈﺮ ﮔﺮﻓﺘﻦ وﺟﻮد اﺷﺒﺎع ﻧﺎﻣﺘﻘﺎرن در ﻋﻤﻠﮕﺮ، از روش ﮐﻨﺘﺮل ﮔﺎم ﺑﻪ ﻋﻘﺐ و ﺗﻠﻔﯿﻖ آن ﺑﺎ ﺗﮑﻨﯿﮏ ﺗﻄﺒﯿﻘﯽ ﺑﺮاي ﺑﻬﺒﻮد ﻋﻤﻠﮑﺮد ﮐﻨﺘﺮلﮐﻨﻨﺪه اﺳﺘﻔﺎده ﺷﺪه و ﭘﺎﯾﺪاري ﺳﯿﺴﺘﻢ ﺣﻠﻘﻪﺑﺴﺘﻪ ﺗﻀﻤﯿﻦ ﻣﯽﮔﺮدد. در اﻧﺘﻬﺎ ﺑﺎ ﮐﻤﮏ ﻧﺘﺎﯾﺞ ﺷﺒﯿﻪﺳﺎزي ﻧﺸﺎن داده ﻣﯽﺷﻮد ﮐﻪ ﺑﺎ وﺟﻮد اﻏﺘﺸﺎش ﭘﻠﻪاي ﺑﺰرگ، دز اﻧﺴﻮﻟﯿﻦ ﺗﺰرﯾﻘﯽ در ﻣﺤﺪوده ﻣﺠﺎز ﺑﯿﻦ ﺻﻔﺮ ﺗﺎ 20 ﻣﯿﻠﯽ واﺣﺪ ﺑﺮ دﻗﯿﻘﻪ ﺑﺎﻗﯽ ﻣﺎﻧﺪه و ﺳﻄﺢ ﮔﻠﻮﮐﻮز ﺧﻮن از ﻣﺤﺪوده ﻣﻨﺎﺳﺐ 130 ﻣﯿﻠﯽﮔﺮم ﺑﺮ دﺳﯽﻟﯿﺘﺮ ﻓﺮاﺗﺮ ﻧﻤﯽرود.

It is essential to control vital variables in patients whose natural control system has been compromised for some reason. One of these vital variables is blood glucose levels. Unfortunately, in people with diabetes (blood sugar), blood glucose levels are not regulated properly. To compensate for this lack, in recent years, several studies and efforts have been made to build and improve the function of the artificial pancreas to control blood sugar. The presence of factors such as multiple uncertainties due to physiological differences in individuals, various activities during the day, delayed effects of carbohydrates on blood sugar levels, stress and exercise make controlling the artificial pancreas a challenging system. But one of the most important challenges in this area, which has not been less addressed in the literature is the limitation on the allowable dose of insulin injected into the artificial pancreas for patients with type 1 diabetes. On the one hand, injecting a high dose of insulin can cause problems such as hyperglycemia issues and on the other hand, injecting a negative dose of insulin is meaningless. In this paper, after selecting the Bergman model and considering the existence of asymmetric saturation in the actuator, the back-stepping control method is used and it is combined with an adaptive technique to improve the controller performance. Finally, simulation results depict that in the presence of large step disturbance, the insulation rate remains in the allowed band of zero to 20 mU/min, and the blood glucose level does not exceed the appropriate level 130mg/dl.