Indonesian Journal of Electrical Engineering and Computer Science Vol. 30, No. 3, June 2023, pp. 1449~1457 ISSN: 2502-4752, DOI: 10.11591/ijeecs.v30.i3.pp1449-1457  1449 Journal homepage: http://ijeecs.iaescore.com Optimal sensor location for adaptive control system in tropical smart greenhouse Folkes Eduard Laumal 1,3 , Herry Suhardiyanto 2 , Mohamad Solahudin 2 , Slamet Widodo 2 1 Department of Mechanical and Biosystem Engineering, Graduate Study Program on Agricultural Engineering Science, IPB University, Bogor, Indonesia 2 Department of Mechanical and Biosystem Engineering, IPB University, Bogor, Indonesia 3 Department of Computer Engineering, Politeknik Negeri Kupang, Kupang, Indonesia Article Info ABSTRACT Article history: Received Sep 27, 2022 Revised Jan 20, 2023 Accepted Feb 4, 2023 The uniform control in greenhouse with technology capabilities is seemingly still difficult to be obtained due to the accuracy uncertainty of the data in certain locations. Considering this case, it is highly necessary to choose the right location for the sensor installation. This study aimed to determine sensor placement locations to support precision control activities, using an arch-type smart greenhouse measuring 8×24 m 2 as the research location. Air temperature was calculated from 12 locations and analyzed for all possible combinations to designate the best sensor point according to the number of sensors. The analysis was conducted using the error-based method to ascertain the number and location of sensors that represent the smart greenhouse. The best location and number of sensors are identified with performance value under 10% and recommended for developing an adaptive control system. Keywords: Adaptive control system Error based method Non-parametric test Sensor Smart greenhouse This is an open access article under the CC BY-SA license. Corresponding Author: Herry Suhardiyanto Department Mechanical and Biosystem Engineering Graduate Study Program on Agricultural Engineering Science, IPB University Bogor, West Java, Indonesia Email: herrysuhardiyanto@apps.ipb.ac.id 1. INTRODUCTION In general, greenhouses are developed in two ways: the traditional model, which relies on the natural climate to support plant growth, and the modern model, which involves various automatic control technologies to support control activity [1]–[3], which use IoT monitoring mechanisms [4], [5] or wireless technology for communication [6]. Several control technology systems for greenhouses have been carried out by Wan et al. [7], who developed an ESP8266-based temperature and humidity controller and placed it in the middle of the greenhouse to environment monitoring and remote control. Ardiansah et al. [8] developed a sensor-based automatic sustainable environment monitoring in greenhouses. Although control can be performed by systems developed for small greenhouses, improper placement of sensors in large greenhouses affects the uniformity and accuracy of control. Non-uniform control can impact the growth of plants inside the greenhouse. Several studies about the placement of sensors have been carried out by several researchers, including Ostachowicz et al. [9], Oleynik et al. [10], Yang et al. [11], Suryanarayana et al. [12], Chen and Gorle [13] and Jaya et al. [14]. These studies are an attempt to identify and determine the location of sensor placement for maximum control and productivity in cultivation. Hu et al. [15] succeeded in identifying sensor locations using an grey correlation degree method in a large-scale laying hen houses. This strategy not only meets the goal of accurately monitoring the hen house temperature, but also saves the hardware cost,