دانشگاه تبریز نشریه مکانیزاسیون کشاورزی 2383-126X 11 2 2026 09 21 Development and Implementation of Electro Pneumatic Control Systems for Mechanized Operation of Combine Harvester Functional Units راه‌اندازی تقسیم کمباین به‌صورت برقی و بادی برای کنترل مکانیزه‌ی اجزای عملکردی 1 13 22313 10.22034/jam.2026.71682.1353 FA اسماعیل یارمطاقلو گروه مهندسی بیوسیستم، دانشکده کشاورزی، دانشگاه بوعلی سینای همدان، همدان، ایران. مجتبی جابری معز گروه مهندسی بیوسیستم، دانشکده کشاورزی، دانشگاه بوعلی سینای همدان، همدان، ایران. Journal Article 2026 02 23 <em>Introduction</em><br />Grain harvesters, as one of the most complex agricultural machines, have numerous subsystems whose precise control plays a decisive role in reducing harvest losses, increasing crop quality, and improving operator ergonomics. In many conventional combines, parts such as the platform, real, thresher, and grain discharge mechanism are controlled mechanically or hydraulically, reduce control accuracy. Advances in pneumatic and electrical systems have made it possible to control these parts with higher accuracy, greater safety, and more appropriate automation capabilities. The purpose of this paper is to present a comprehensive structure for the setup and evaluation of a combined electric-pneumatic system in wheat harvesters. In recent years, advanced mechanization in harvesting machines, especially grain combines, has become one of the central issues in increasing productivity and reducing cost per unit area. Currently, many domestic combines use traditional mechanical or hydraulic systems to perform the operations of raising and lowering the harvesting platform, controlling the reals, and discharging straw and wheat, which have limitations such as response delay, oil leakage, high energy consumption, and increased component wear.<br /><em>Materials and Methods</em><br />In this study, a hybrid electric-pneumatic control system was designed, simulated, and implemented for four key parts of the combine harvester: 1- platform raising and lowering, 2- fork control (horizontal and vertical movement), 3- straw control, and 4- wheat discharge through the outlet pipe. In the present design, the electric control circuit is combined with a PLC control unit and pneumatic actuators including solenoid valves and double-way cylinders to achieve accurate and fast control of movements. The system was modeled in MATLAB/Simulink software and tested in a practical environment with position and pressure sensors. This system was designed and manufactured at the Sabzabad Hegmataneh Combine Harvester Factory in Hamadan (New Iran) and field tested in the wheat fields of Shurin village, Hamadan city. The proposed system consists of an electrical control circuit and a pneumatic power circuit. The control circuit consists of an industrial PLC unit, cabin control switches, relays, and a 24V power supply module. The pneumatic circuit consists of an air compressor, a storage tank, a air monitoring unit (FRL), 5/2 solenoid valves, and two-way cylinders.<br /><em>Results and Discussion</em><br />The results of this study demonstrated that the proposed electro-pneumatic control system significantly improved the dynamic and operational performance of the combine harvester. Field experiments showed that the average response time of the controlled mechanisms was reduced to less than 0.8 s, representing a considerable improvement compared to conventional hydraulic systems. MATLAB/Simulink simulations confirmed the faster transient response and higher stability of pneumatic actuators under PLC-based control. Energy consumption measurements indicated a reduction of approximately 23% relative to the hydraulic counterpart. Furthermore, positioning accuracy was enhanced, with a maximum error below 3%. Vibration analysis revealed a reduction of nearly 30%, leading to lower mechanical stress and extended component lifespan. The overall system reliability reached 0.93, exceeding that of typical domestic combine harvesters. These results confirm the feasibility of electro-pneumatic systems as an effective solution for upgrading conventional harvesting machines and enabling future intelligent control applications.<br /><em>Conclusion</em><br />The results show that integrating electro-pneumatic actuators with PLC-based control effectively addresses key limitations of conventional hydraulic systems in combine harvesters. Faster response times are mainly due to the lower inertia of pneumatic actuators and direct on–off solenoid valve control, which removes delays from fluid compressibility and hydraulic pump circuits. Good agreement between MATLAB/Simulink simulations and field measurements confirms the validity of the dynamic model and the accuracy of the proposed control architecture. Overall energy consumption is reduced by eliminating continuously running hydraulic pumps and leakage losses. The electro-pneumatic system also improves positioning accuracy through closed-loop control with position sensors and reduces vibration by providing smoother motion, lowering impact loads and extending component service life. With a reliability index of 0.93 and successful real-world testing, the system is technically feasible and suitable for industrial use. Overall, it is a promising, cost-effective alternative for modernizing domestic combine harvesters and supports future intelligent, sensor-based control and IoT applications.<br /><em>Acknowledgement</em><br />Thanks to the staff and personnel of New Iran Combine Harvester Company (Sabzabad Hegmataneh).  <strong>در سال‌های اخیر، مکانیزاسیون پیشرفته در ماشین‌های برداشت به‌ویژه کمباین‌های غلات، به یکی از موضوعات محوری در افزایش بهره‌وری و کاهش هزینه‌ در واحد سطح تبدیل‌شده است. در شرایط فعلی، بسیاری از کمباین‌های داخلی از سیستم‌های مکانیکی یا هیدرولیکی سنتی برای انجام عملیات بالا و پایین کردن پلتفرم برداشت، کنترل چنگالی، تخلیه‌ی کاه و گندم استفاده می‌کنند که دارای محدودیت‌هایی چون تأخیر در پاسخ، نشت روغن، مصرف بالای انرژی و افزایش سایش اجزا هستند. در این پژوهش، یک سامانه‌ی کنترل ترکیبی برقی</strong><strong>–</strong><strong>بادی برای چهار بخش کلیدی کمباین طراحی، شبیه‌سازی و اجرا شد: ۱- بالا و پایین کردن پلتفرم، 2- کنترل چنگالی (حرکت افقی و عمودی)، 3- کنترل کاه کوب و 4- تخلیه‌ی گندم از طریق لوله‌ی خروجی. در طراحی حاضر، مدار فرمان الکتریکی با واحد فرمان </strong><strong>PLC</strong><strong> و عملگرهای بادی شامل شیرهای سلونوئیدی و سیلندرهای دوطرفه ترکیب‌شده است تا کنترل دقیق و سریع حرکت‌ها حاصل شود. سیستم در نرم‌افزار </strong><strong>MATLAB/Simulink</strong><strong> مدل‌سازی و در محیط عملی با حسگر موقعیت و فشار آزمایش شد.</strong> <strong>این سامانه در کارخانه کمباین سازی نیوایران (سبزآباد هگمتانه) همدان طراحی و ساخته شد و در مزارع گندم روستای شورین از توابع شهرستان همدان مورد آزمون میدانی قرار گرفت. نتایج آزمایش‌­ها نشان داد که سامانه پیشنهادی ازنظر زمان پاسخ، مصرف انرژی، دقت کنترلی و قابلیت اطمینان عملکرد، به‌طور معناداری نسبت به سیستم‌های هیدرولیکی متداول برتری دارد</strong><strong>.</strong><strong> زمان پاسخ کمتر از 8/0 ثانیه، مصرف انرژی کل سیستم در مقایسه با مدار هیدرولیکی مشابه ۲۳</strong><strong>٪</strong><strong> کاهش و راندمان کلی عملکرد مکانیزم‌ها ۱۷</strong><strong>٪</strong><strong> افزایش یافت. ضریب قابلیت اطمینان به 93/0 رسید که نسبت به میانگین کمباین‌های تولید داخلی (74/0) بهبود قابل‌ملاحظه‌ای را نشان داد و افزایش دقت موقعیت تا سطح خطای کمتر از ۳</strong><strong>%</strong><strong> نسبت به سیستم هیدرولیکی سنتی به دست آمد. نتایج تجربی همچنین بیانگر کاهش محسوس لرزش و افزایش طول عمر اجزای مکانیکی تا ۳۰</strong><strong>%</strong><strong> بود.</strong> https://jam.tabrizu.ac.ir/article_22313_d70862ab92688d5140b845231cac1c2c.pdf