Surveying of Underwater Robot for Marine Exploration

Transcription

1 IJSTE - International Journal of Science Technology & Engineering Volume 2 Issue 09 March 2016 ISSN (online): X Surveying of Underwater Robot for Marine Exploration D. S. Vidhya Puja S Patil Assistant Professor Rishwesh Dalvi Sunny Cardozo Abstract This paper describes a small underwater robot designed for marine exploration, with sensors and XBee for wireless transmission. The robot is based on the Arduino platform, which is used extensively as an experimental testbed. The movement of the robot will be controlled by wirelessly transmitting commands via Xbee. The components and construction of the robot are described. Preliminary tests of ph measurement, pressure measurement and temperature measurement are analysed and reported. Keywords: wireless transmission, Xbee, arduino testbed, ph sensor, temperature sensor, pressure sensor I. INTRODUCTION Earth is roughly 71% covered in water and a large portion of it is unexplored. This underwater robot is a low-cost tele-robotic submarine built with the goal of making underwater exploration affordable. It has the ability to collect valuable data like temperature, pressure, ph value and species monitoring at different depths. Based on the paper on robot operating to sense water resources i.e., sea animals behaviour, sand level, water gravity [1], XBee communication, an enhanced wireless system is used for data transmission wirelessly. In this prototype, we introduce a new idea of wireless robot control system which is used as a tool to perform wireless control of the robot while it measures the parameters underwater. XBee is used for wireless transmission of the data. Arduino is used for interfacing sensors and motors. It is an open-source platform used for building electronics projects. Arduino consists of both a physical programmable circuit board (often referred to as a microcontroller) and a piece of software, or IDE (Integrated Development Environment) that runs on your computer, used to write and upload computer code to the physical board. In recent trends the robots are working in vast applications, if our concept is adopted, it will enhance and increasing monitoring function done by the robot underwater. II. ROBOTS ELECTRONIC MODULE The electronic module covers all of the electronic components required for the functioning of the ROV i.e. sensors, microcontrollers etc. Fig. 1: All rights reserved by 220

2 Xbee Communication For Xbee to transmit and receive data two Xbees are need one of which works as a transmitter and the other works as a receiver. Xbee can work either in AT mode or API mode. In AT mode is used when the network required isn t complex and only point to point connections are required. API mode is used for much complex networks where a central Xbee acts as a coordinator and the others act as end points. Xbee is connected to the PC using an interface that enables the use of an USB cable. Fig. 2: For communication to take place between 2 Xbees, one has to be configured as a router and the other as a coordinator, and to configure the Xbees a serial terminal program is used. For Xbees to communicate with each other, the three of the most important XBee settings PAN ID, MY address, and destination address have to be specified. PAN ID: Personal area network ID: The network ID is a hexadecimal value between 0 and 0xFFFF. XBees can only communicate with each other if they have the same network ID My Address: Each XBee in a network should be assigned a 16-bit address which is referred to as MY address or the source address. -DESTINATION ADDRESS: The destination address, determines which source address an XBee can send data to. For one XBee to be able to send data to another, it must have the same destination address as the other XBee s source Software XCTU: XCTU is a free multi-platform application designed to enable developers to interact with Digi RF modules through a simple-touse graphical interface. It includes new tools that make it easy to set-up, configure and test XBee RF modules. Arduino IDE:The open-source Arduino Software (IDE) makes it easy to write code and upload it to the board. It runs on Windows, Mac OS X, and Linux. The environment is written in Java and based on Processing and other open-source software Temperature Sensor - DS18B20 DS18B20 is a Digital Sensor. Measures Temperatures from-55 C to +125 C, ±0.5 C Accuracy from -10 C to +85 C.In DS18B20, Each DS18B20 has a unique 64-bit serial code, which allows multiple DS18B20s to function on the same 1-Wire bus,so information is sent to/from the sensor over a 1-Wire interface, so that only one wire (and ground) needs to be connected from a central microprocessor to a DS18B20.The resolution of the DS18B20 is configurable (9, 10, 11, or 12 bits), Fig. 3:DS1B20 sensor All rights reserved by 221

3 Fig. 4: Interfacing DS18B20with Arduino with 12-bit readings the factory default state. This equates to a temperature resolution of 0.5 C, 0.25 C, C, or C. ph Sensor ph sensor is made up of ph electrode and a ph meter. The analog ph meter, specially designed for Arduino controllers and has built-in simple, convenient and practical connection and features. Fig. 5: It has an LED which works as the Power Indicator. A BNC connector and PH2.0 sensor interface. To use it, just connect the ph sensor with BNC connector, and plug the PH2.0 interface into the analog input port of any Arduino controller. It gives a voltage reading for every corresponding ph value. The ADC of the Arduino takes in input as analog and gives the output in digital form Pressure sensor DSSPD015Bhybrid The hybrid series MEMS made piezo resistive pressure sensors provides a convenient way to use Surface mount technology with a flexible way of air connection. Due to the production process these sensors are ideal for high volume applications and automated assy. Two kind of air connections are available, a cap with hole and a cap using 1/8 tube connection. Fig. 6: All rights reserved by 222

4 Electrical Specifications Circuit Connection Of Pressure Sensor. Fig. 7: III. ROBOTS NAVIGATION MODULE Servo Motors Fig. 8: A servomotor is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity and acceleration. It is used as a rudder to control the direction of the Aquabot. All rights reserved by 223

5 Specification of the servo motor used- Modulation: Anaog. Torque: 4.8V: 25.0 Oz-in Speed: 4.8V:0.12 sec/60 Servo motor is used as a rudder Brushless Dc Motor Brushless DC electric motor (BLDC motors, BL motors) also known as electronically commutated motors (ECMs, EC motors) are synchronous motors that are powered by a DC electric source via an integrated inverter/switching power supply, which produces an AC electric signal to drive the motor. It is used for depth control and forward movement of Aquabot. Specification of the brushless dc motor used- Voltage: v RPM/V(Kv): 1200 At 10v rpm is approximately 12,000 Electronic Speed Controller Fig. 9: An electronic speed control or ESC is an electronic circuit with the purpose to vary an electric motors speed, its direction and possibly also to act as a dynamic range. ESCs are often used for brushless motors essentially providing an electronically generated three-phase electric power low voltage source of energy for the motor. IV. CONCLUSION As things stand, underwater exploration is a relatively new and expensive field. We aim to change that and make it easily accessible to individuals. This report outlines the fundamentals of the prototype of a marine ROV. The operation of the arduino and its programming has been studied so far. Interfacing the temperature sensor, brushless dc motor and the servo motor with the arduino has been successfully implemented. REFERENCES [1] Vitaly Bokser, Carl Oberg, Gaurav S. Sukhatme, and Aristides Requicha, A SMALL SUBMARINE ROBOT FOR EXPERIMENTS IN UNDERWATER SENSOR NETWORKS, [2] Govindarajan.R, Arulselvi.S, Thamarai.P, Underwater Robot Control Systems, 1 April 2013, International Journal of Scientific Engineering and Technology [3] Yufeng Wei, Fang Liu, Fei Hu, Fanrang Kong, The structure design of the mini underwater robot, School of Engineering Science, University of Science and Technology of China [4] HOWARD H.WANG,STEPHEN M. ROCK, The Design and Development of an Intelligent Underwater Robot, Aerospace Robotics Laboratory Department of Aeronautics and Astronautics, Stanford University Stanford All rights reserved by 224