International Conference on Mechanical, Industrial and Materials Engineering 2017 (ICMIME2017) 28-30 December, 2017, RUET, Rajshahi, Bangladesh. Paper ID: RT-70 A proposal for an autonomous robotic model ship for continuous measurement of turbidity using wireless network system and GPS Maqsood Mansur 1 , Preetom Kumar Sarker 2 , Md. Safwan Ahsanullah 1 , Md. Kamruzzaman Prodan 3 , Kaustuv Brohmachary 1 , Sakib Noor 1 and Doyal Kumar Sarker 1 1 Department of Naval Architecture and Marine Engineering, Bangladesh University of Engineering and Technology, Dhaka-1000, Bangladesh 2 Department of Civil Engineering, Bangladesh University of Engineering and Technology, Dhaka- 1000, Bangladesh 3 Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology, Dhaka-1000, Bangladesh E-mail: maqsoodmansur@outlook.com, 211bondhonpksb@gmail.com, safwanahsanullah@gmail.com, kamruzzaman.2301@gmail.com, kaustuv036@gmail.com, sakib9493@gmail.com, doyalkumar94@gmail.com Abstract Turbidity is a measure of haziness of water body. The measurement of turbidity is an important test to determine water quality. We propose a schematic for an autonomous vessel that will measure turbidity at prescribed locations using wireless networking and GPS tracking systems, thereby, presenting opportunity for continuous measurement of turbidity in real time with minimum human supervision. An autonomous model ship should be designed and fitted with wireless network system and GPS. A simple turbidimeter with necessary modifications should be mounted inside this vessel with provisions for collecting water samples directly from the water body using pumps and other necessary accessories. The vessel will be provided with preloaded sets of co-ordinates of locations where water quality test should be carried out. Using GPS the vessel will collect sample from each prescribed location. At regular intervals the turbidity test will be carried out and the results will be sent back. Keywords: turbidity, autonomous robotic model ship, wireless network system, GPS, real-time data. 1. Introduction Turbidity refers to the cloudiness of a fluid medium and is quantified by the intensity of light scattered by particles suspended in the medium [1] . For the purposes of water quality monitoring, the American Water Works Association defines turbidity as a nonspecific measure of the amount of particulate material in water including clay, silt, finely divided organic, and inorganic matter [2] . The suspended colloid-sized particles (with diameters roughly between one nanometer and one micrometer) are chiefly responsible for turbidity in water. The particles may have high specific surface area. The term suspended solids refers to particles that typically range from 10 to 100 microns in diameter. These particles often represent the majority of chemical contamination in a water supply as they can adsorb water quality contaminants such as heavy metals or pesticides [3] . Apparently such particles provide microscopic refuges for pathogens, absorb and scatter ultraviolet light (rendering UV light less effective as a disinfectant), and often have a high fraction of natural organic matter, which can consume the oxidizing power of chemical disinfectants such as chlorine and ozone and may form toxic by-products in the process [4] .The effectiveness of disinfection processes for drinking water treatment can be significantly impaired by these particles causing turbidity. Moreover, the suspended particles absorb heat from sunlight, thus warming the turbid waters, as a result of which the concentration of oxygen in the water gets reduced. The suspended particles scatter the light, decreasing the photosynthetic activity of plants and algae and reducing the concentration further. Turbidity is therefore recognized, both in the engineering literature and in regulations set by the Environmental Protection Agency (EPA), as an important indicator of the cleanliness, drinkability and usability of water [5–7] . According to Bangladesh Environment Conservation Rules (1997), acceptable turbidity for drinking water is considered to be 10 NTU (Nephelometric Turbidity Unit). Turbidity measurement is a qualitative parameter for water but its traceability to a primary standard allows the measurement to be applied as a quantitative measurement. When used as a quantitative measurement, turbidity is typically reported generically in turbidity units (TU’s). The primary standard for thi s parameter is a polymer compound known as formazin and this standard provides the traceable means for all other turbidity standards and is used to calibrate all types of turbidity meters. The developed polymer was matched to a gravimetric mass