Introduction to Robotics

Transcription

1 Two Day Hands on Workshop on Introduction to Robotics This workshop is aimed at Robotics hobbyists and students who wish to learn the art of building sophisticated robots. Building a robot is just the beginning; most people achieve this with moderate effort. What gives our design a winning edge is the ability to adapt to the environment and to make intelligent decisions. This is typically achieved by adding an on board microcontroller. The main challenge is to interface this processing unit with sensors and make our robot do things in the most efficient and reliable manner. This not only involves a good knowledge of sensors but requires sound programming fundamentals. The idea is to know our microcontroller well so we can plan robot design keeping in mind what, where, how and how many sensors/actuators can be interfaced. The workshop covers essential theory combined with hands on sessions to give a realistic view of what goes into building a successful robot. Participants get to implement the concepts learned on the SPARK IV platform, a state of the art mobile robotics research platform developed by IIT Bombay s Embedded & Real Time Systems Lab along with NEX Robotics for IIT s teaching requirements. At the end of the course, the participant is able to build microcontroller based applications, and have familiarity with hardware and robotic programming. Program Faculty Prof. Kavi Arya, Associate Professor, Computer Science & Engineering Dept.,IIT Bombay. Details of this program will be conducted by ERTS research staff who between them have extensive experience in designing robots for education and for competitions. Our lab has numerous years of experience in building robots, delivering industry projects, etc. Participants: This workshop is ideal for working professionals who wish to get an entry into programming robots, for teachers at school/college level who wish to add robot based assignments to motivate their students and for students who wish to equip themselves to develop robotic applications for interest or for participating in competitions. Hence we have oriented this program towards: Participants from academic institutes Practicing engineers from various private, public, government organizations and industries Scientists/engineers from R&D establishments and consultants Students

2 Pedagogy: Course based on lecture, hands on sessions and discussions Duration and Mode of Delivery Duration of the program is 2 days. Program Dates 16 th and 17 th October Venue The program will be conducted at IIT Bombay Batch Size Minimum number of participants required to offer the program is 40 and maximum number of participants is 60. Last date for Registration Nomination for the course will be accepted up to 14 October Registration Completed registration form along with Demand Draft or cheque for requisite amount drawn in favor of The Registrar, IIT Bombay,(CEP Account) payable at Mumbai. If payment is by a cheque, it should be payable at par at Mumbai. DD / Cheque should be sent to the Program Coordinator on or before the last date. Course Fee Course fee is Rs.5,000/ (rupees five thousand only).the course fees are inclusive of one set of course material, AVR development board, working lunch, tea/coffee and snacks (accommodation should be paid directly by the participant, please refer to form at the last page) Fees once paid are not refundable under any circumstances. In special cases, replacement of registered candidate by another eligible candidate may be permitted. Companies please note that the courses conducted by IIT are exempt from Income Tax and hence no TDS should be deducted. Lodging & Boarding Guest House facility in the campus is available for limited number of participants on twin sharing basis, on payment as per actuals. Please ensure to mark your request for accommodation in the IIT Guest House on the registration form.

3 PLEASE SEND THE REGISTRATION FORM ALONG WITH THE FEE SO AS TO REACH TO THE COURSE COORDINATOR ON OR BEFORE October 14, Registration form can be sent via also. Please address all communication to: Prof. Kavi Arya ERTS Lab, KReSIT bldg. (level 1) CSE Dept., IIT Bombay, Powai Mumbai Phone: (ERTS lab/ 9am 5pm) The workshop has two sessions: theory session and a lab session Fundamentals of robotics (Theory Session) Sensing Locomotion Motion Control Power Communication Location Determination Sensing This session covers how to interface sensors, interpret and analyze their signals. Apart from basic sensing, it is important to be able to do Sensor fusion which means to process signals received from multiple sensors and use them for high level decision making. We will also describe how to position these sensors in order to implement optimal sensing. This is followed by discussion on how to build our own customized sensors. Types of sensors covered Light Temperature Magnetic field Ultrasonic Position Direction Touch Infrared Image

4 Locomotion This session covers the design and implementation of the mechanism for the robot s movement. Different modes of locomotion are discussed with more emphasis on widely used wheel based and legged robots. A brief overview of locomotion mechanism for airborne, underwater and floating robots will be given. Concepts such as centre of gravity, balance, optimal power transfer, and optimal placement of actuators are explained. Motion Control This session explores ways in which robot s movements can be controlled. It involves topics such as, how to achieve good control on DC and stepper motors, fundamentals of closed loop control etc. A comparative study of DC motors vs. Stepper motors is done and pros and cons of control strategies involved are explained. Main constraints while designing robots locomotion is power consumption. Power optimized motion control and batteries involved will be discussed. Types of motors that can be used for locomotion: DC Motors Stepper Motors Servo Motors Power Power management and its importance Selection criteria for the batteries Charging methods for different types of the batteries Safety instructions for these batteries. Introduction to different batteries o NiCad o Lithium ion o Lead Acid Communication A communication module defines how a robot communicates with external entities. Primary aspects of designing a communications module involve communication protocols, modulation schemes, shielding, range and power consumption. Location Determination Once we get our robot running, we want to find out where it is located and what its orientation. This session describes methods that can be used for robot location determination. Position encoder based

5 Grid based Infrared based Acoustics based Image based Inertial based Lab session All of the above concepts are implemented by students on the SPARK IV robotic platform. SPARK IV is a universal robotic research platform used in IIT Bombay to teach concepts of embedded systems. This session starts with an introduction to (IDEs) Integrated Development Environments used to program the AVR series of microcontrollers such as ICC AVR and AVR Studio. Using this environment we teach students to program the microcontroller on the SPARK IV platform while interfacing it with its peripherals. I/O Port Programming Position and Velocity Control LCD Interfacing Robot Sensor Interfacing Serial Communication Wall Hugging White Line Following Adaptive Cruise Control I/O Port Programming To start off with the basics, we guide the students through configuring the ports as input or output ports. A simple program to turn ON and OFF a buzzer is written, downloaded onto the Fire Bird and executed. Then programming the ports to read input from the bump sensors, we would program the buzzer to beep every time the bump sensor is pressed. Position and Velocity Control Next we move onto evoking the actuators on the robot. We have two DC geared motors on board which we would program to move the robot forward, backward, left and right using differential drive configuration. But, simply motion of the robot isn t enough. How would we control the distance it needs to travel or the degree it needs to turn? That brings us to the notion of a closed loop system. A feedback loop would be required to control the exact position of the robot. This is achieved by using shaft/position encoder. These shaft encoders give their feedback to the interrupts on the microcontroller thus providing the system with a closed loop control. In this session participants will also learn concept of pulse width modulation (PWM), Interrupts.

6 LCD Interfacing We now move onto interfacing the LCD with the microcontroller. LCD is one of the most essential part of mobile robot for robot human interaction. Writing code for the LCD for the first time is often a tedious job. Programming the LCD requires lengthy and intricate codes. In this session we will teach how to program the LCD. This is made simple through our libraries which would be available to the students. The tricks and simplified methods for LCD interfacing would be taught to the students. This would be used ahead to display various sensor values and other parameters required for proper functioning of the robot. Robot Sensor Interfacing SPARK IV carries a large array of sensors like IR proximity sensor, SHARP IR range finder, White line sensors, Directional light intensity sensors and two position encoders. Most of these sensors give out analog values as their outputs, which are converted to digital data by the inbuilt analog to digital converter of the microcontroller. In this session we learn how to acquire sensor values and process them and display it on the LCD. Serial Communication We learn how to control the robot using serial port of the robot. This gives students a clear idea of the fundamentals of serial communication and explains the intricacies involved in working with the serial port, which we use for several other applications of control and data acquisition. Wall Hugging Our next step is to integrate all these acquired skills to combine sensing, intelligence, and actuation. By giving intelligence to the robots they can react intelligently to surrounding environment. For this experiment we use Infrared Proximity sensors. As each sensor is activated we control the motion of the robot. This is our first step to giving intelligence to the robot. White Line Following To guide the robot to follow a path i.e. to define its motion on the go, depending upon the road ahead would be a great asset. We do this by using a closed loop control. The analog values we get from the white line sensors are used as input to controlling the robot. The robot is put into a continuous loop where it scans sensor values and makes its own decision to traverse forward following the white line on the ground. From here, we come to the concepts of localization i.e. navigating the robot on a grid of white lines. These are among the problem statements of various competitions like ROBOCON and inter collegiate Techfests. The mission being to program an autonomous robot to navigate through a grid and perform required tasks. We ask it to detect nodes i.e. intersections using white line sensors and take turns depending upon the route chosen at the n th node as decided. These decisions could also be made with respect to the obstacles detected by bump sensors and further processed to give the robot a well defined and accurate control.

7 Adaptive Cruise Control Combining the above programs we wish to perform a challenging task to teach our robot to cruise on its own maintaining a safe distance and following a specified route. In this experiment we will use the distance acquired from the SHARP sensors for maintaining the safe distance from the front robot, while the white line sensors will be used to follow white line. This workshop gives us a clear idea on how to use the different sensors and even construct a few sensors on our own. These sensors when compounded may be used to do several complex tasks as per requirement which is the actual basis of this entire workshop i.e. to move robotics to the next level, a step ahead from the traditional wired and wireless robots which are becoming obsolete to something looking towards the future. Prerequisites: Familiarity with C programming Familiarity with Microcontroller/Microprocessor architecture Previous exposure to building simple wheeled platforms will be an added advantage

8 REGISTRATION FORM Two day CEP Course on Introduction to Robotics October 16 17, 2008 NAME (PRINT) : Gender: M / F DESIGNATION: ORGANIZATION: MAILING ADDRESS : TELEPHONE : (O) (R) FAX: MOBILE: QUALIFICATIONS : EXPERIENCE : Yrs. IIT Guest House accommodation required?* YES / NO PAYMENT: D.D. No. Date Rs. 5,000/= Drawn on [Demand draft should be drawn in favour of "The Registrar, IIT Bombay (CEP A/c)"] Date: Signature of Applicant *Guest House bill to be paid directly by the participant. (XEROX ADDITIONAL COPIES OF THIS FORM, IF NEEDED)