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List of figure Figure Page No. 1.1 type of robot 5 1.2 A soldier preparing telerobot 6 1.3 AGV type robot 6 1.4 Industrial robot 7 3.1 Pin configuration of AT-89S52 13 3.2 18-PIN DTMF IC 13 3.3 16 –PIN L293D IC 14 5.1 block diagram of cell phone operated land rover 17 6.1 circuit diagram of cell phone operated land rover 19 7.1 capacitor 21 7.2 construction of capacitor 23 7.3 fixed value ceramic capacitor 24 7.4 resistor 25 7.5 diode 27 7.6 symbol of electric crystal 28 7.7 construction of quartz crystal 29 7.8 push button 30 7.9 geared dc motor 31 Page | 1 7.10 6v dc lead acid battery 33 7.11 18 pin DIP packing DTMF IC 35 7.12 AT-89S52 DIP packing 38 7.13 16-pin DIP packaging L293D motor driver IC 41 7.14 IC 74LS04 42 8.1 screen of the keil software new open 44 8.2 create project environment 45 8.3 select a device 46 8.4 write controller’s program in the source file 46 8.5 compilation of the program 47 8.6 debugging of the program 48 8.7 creating hex 49 8.8 wheels, motors, front wheels, motor clamps and bord 52 9.1 action performed corresponding to the keys pressed 53 Page | 2 ABSTRACT Conventionally, wireless controlled robots user circuits, which have a drawback of limited working range, limited frequency range and limited control. Use of mobile phones for robotic control can overcome these limitations. It provides the advantages of robust control, working range as large as the coverage area of the service provider, no interference with other controllers and up to twelve controls. Although, the apperanceand capabilities of robot vary vastly, all robots share the feature of a mechanical, movables structure under some form of control. The control of robot involves three distent phases: perception, processing, action. Generally, the preceptors are sensors mounted on the robot, processing is done by the on board microcontroller and the task is performed using motors or with some other actuators. In the project the robot is controlled by a mobile phone that makes a call to the mobile phone attached to the robot. In the course of a call, if any button is pressed a tone corresponding to the button pressed is heard at the other end called ‘Dual Tone Multiple frequency’ (DTMF) tone. The robot receives these tones with help of phone stacked in the robot. The received tone is processed by the microcontroller with the help of DTMF decoder ic cm8870 .these ic sends a signals to the the motor driver ic l293d which derives the motor forward, revarse…etc Page | 3 Chapter: 1 Introduction 1) What are the robots? A robot is a mechanical or virtual artificial agent, usually an electro-mechanical machine that is guided by a computer program or electronic circuitry. Robots can be autonomous or semiautonomous. By mimicking a life like appearance or automating movements, a robot may convey a sense of intelligence or thought of its own. Robotics is the branch of technology that deals with the design, construction, operation, and application of robots, as well as computer systems for their control, sensory feedback, and information processing. These technologies deal with automated machines that can take the place of humans in dangerous environments or manufacturing processes, or resemble humans in appearance, behavior, and/or cognition. Many of today's robots are inspired by nature contributing to the field of bio-inspired robotics. As mechanical techniques developed through the Industrial age, more practical applications were proposed by Nikola Tesla, who in 1898 designed a radio-controlled boat. Electronics evolved into the driving force of development with the advent of the first electronic autonomous robots created by William Grey Walter in Bristol, England in 1948. The first digital and programmable robot was invented by George Devol in 1954 and was named the Unimate. It was sold to General Motors in 1961 where it was used to lift pieces of hot metal from die casting machines at the Inland Fisher Guide Plant in the West Trenton section of Ewing Township, New Jersey. Robots have replaced human in the assistance of performing those repetitive and dangerous tasks which humans prefer not to do, or are unable to do due to size limitations, or even those such as in outer space or at the bottom of the sea where humans could not survive the extreme environments. Page | 4 1.1) Types of robots Fig. 1.1 types of robot 1) Mobile robots - telerobots\Military robots -Space probes -agv 2) Industrial robots 3) Service robots 4) Modular robots 1.1.1) Mobile robots Mobile robots\telerobots have the capability to move around in their environment and are not fixed to one physical location. An example of a mobile robot that is in common use today is the automated guided vehicle or automatic guided vehicle (AGV). An AGV is a mobile robot that follows markers or wires in the floor, or uses vision or lasers. Page | 5 Fig. 1.2 a soldier prepare telerobot for mission Fig. 1.3 an AGV type robot in exhibition Page | 6 Mobile robots are also found in industry, military and security environments. They also appear as consumer products, for entertainment or to perform certain tasks like vacuum cleaning. Mobile robots are the focus of a great deal of current research and almost every major university has one or more labs that focus on mobile robot research. 1.1.1) Industrial robot Industrial robots usually consist of a jointed arm (multi-linked manipulator) and an end effector that is attached to a fixed surface. One of the most common type of end effector is a gripper assembly. The International Organization for Standardization gives a definition of a manipulating industrial robot in ISO 8373: "An automatically controlled, reprogrammable, multipurpose, manipulator programmable in three or more axes, which may be either, fixed in place or mobile for use in industrial automation applications." Fig. 1.4 an industrial robot working into the casting company Page | 7 This definition is used by the International Federation of Robotics, the European Robotics Research Network (EURON) and many national standards committees. 1.1.3) Service robots Most commonly industrial robots are fixed robotic arms and manipulators used primarily for production and distribution of goods. The term "service robot" is less well-defined. The International Federation of Robotics has proposed a tentative definition, "A service robot is a robot which operates semi- or fully autonomously to perform services useful to the well-being of humans and equipment, excluding manufacturing operations." 1.1.4) modular robots Modular robots are a new breed of robots that are designed to increase the utilization of the robots by modularizing the robots. The functionality and effectiveness of a modular robot is easier to increase compared to conventional robots. These robots are composed of a single type of identical, several different identical module types, or similarly shaped modules, which vary in size. Their architectural structure allows hyper-redundancy for modular robots, as they can be designed with more than 8 degrees of freedom (DOF). Creating the programming, inverse kinematics and dynamics for modular robots is more complex than with traditional robots. Modular robots may be composed of L-shaped modules, cubic modules, and U and H-shaped modules. ANAT technology, an early modular robotic technology patented by Robotics Design Inc., allows the creation of modular robots from U and H shaped modules that connect in a chain, and are used to form heterogeneous and homogenous modular robot systems. These “ANAT robots” can be designed with “n” DOF as each module is a complete motorized robotic system that folds relatively to the modules connected before and after it in its chain, and therefore a single module allows one degree of freedom. The more modules that are connected to one another, the more degrees of freedom it will have. L-shaped modules can also be designed in a chain, and must become increasingly smaller as the size of the chain increases, as payloads attached to the end of the chain place a greater strain on modules that are further from the base. ANAT H-shaped modules do not suffer from this problem, as their design allows a modular robot to distribute pressure and impacts evenly amongst other attached modules, and therefore Page | 8 payload-carrying capacity does not decrease as the length of the arm increases. Modular robots can be manually or self-reconfigured to form a different robot, that may perform different applications. Because modular robots of the same architecture type are composed of modules that compose different modular robots, a snake-arm robot can combine with another to form a dual or quadra-arm robot, or can split into several mobile robots, and mobile robots can split into multiple smaller ones, or combine with others into a larger or different one. This allows a single modular robot the ability to be fully specialized in a single task, as well as the capacity to be specialized to perform multiple different tasks. Page | 9 Chapter-2 Problem Definition 2) Problem definition To operates a land rover( which is simple car in our project) remotely in very wide area. 2.1) Detailed problem definition In this world we live in era of fast growing and people of this era want to decreases human working. They want to be protected from any dangerous situation. 2.2) What is need of this cell-phone operated land rover? Conventionally, wireless-controlled robots use RF circuits,which have the drawbacks of limited working range, limited frequency range and limited control. Use of a mobile phone for robotic control can overcome these limitations. It provides the advantages of robust control, working range as large as the coverage area of the service provider,no interference with other controllers and up to twelve controls. Although the appearance and capabilities of robots vary vastly, all robots share the features of a mechanical, movable structure under some form of control. The control of robot involves three distinct phases: reception, processing and action. Generally, the preceptors are sensors mounted on the robot, processing is done by the on-board microcontroller or processor, and the task (action) is performed using motors or with some other actuators. 2.3) Project scope Remote control vehicles have various Scientific uses including hazardous environments, working in the deep ocean , and space exploration. The majority of the probes to the other planets in our solar system have been remote control vehicles, although some of the more recent ones were partially autonomous. The sophistication of these devices has fueled greater debate on the need for manned space flight and exploration. The Voyager I spacecraft is the first craft of Page | 10 any kind to leave the solar system. The martin explorers Spirit and Opportunity have provided continuous data about the surface of Mars since January 3, 2004. Page | 11 Chapter 3 Project Plan 3) Project plan In order to control the robot, you need to make a call to the cell phone attached to the robot from any phone, which sends DTMF tunes on pressing the numeric buttons. The cell phone in the robot is kept in 'auto answer' mode so after a ring, the cell phone accepts the call. Now you may press any button on your mobile to perform actions like move forward, move left, move right, move backward or to stope robot. 3.1) To control robot To control robot we use micro controller AT-89s52, DTMF IC, motor driving IC L293D and two cell phones. When dtmf signal is received by the cell phone connect in the robot that generates particular freq signal for each button so this frequency will convert into the binary code by the DTMF IC. Output is given to the controller IC. According to output of the DTMF IC controller will makes out pin of output port (which is selected in program) makes high. Then this voltage will given to the L293D motor driver IC. This IC will RUN motors connected with it according to the given input. Page | 12 Figure 3.1Pin configuration of DIP type micro controller AT-89S52 Figure 3.2 18-pins DIP DTMF IC Page | 13 Fig. 3.3 16-pin dip L293D IC Page | 14 Chapter: 4 Feasibility 4.1 Financial feasibility The resources used in this project are quite feasible financially. Components list: 1. Semiconductors IC1-MT8870 DTMF decoder IC2-ATMEL89S52 IC3-L293D motor drive IC4-74LS04 NOT gate D1, D2-1N4007 rectifier diode 2. Resistors 100-Kilo-ohm kilo-ohm 10-kilo-ohm 3. Capacitors 0.47uF ceramic disk 0.22pF ceramic disk 0.1uF ceramic disk 25v electrolytic capacitor 4. Miscellaneous Page | 15 3.57MHz Crystal 12MHz Crystal Push to on switch 6V, 50-rpm geared DC motor Batt-6V, 4.5Ah battery Robot’s mechanical body General purpose PCB The list of components given above shows that all the components are cheap and feasible. 4.2) Resource feasibility All the resources used in this project are easily available. All ics are easily available and they are not so expensive. But robot mechanical body and battery of 6v is quite expensive. They are easy to mount on pcb. 4.3) Technical feasibility After we gave our idea to the industry person, the industry person told that my idea was quite feasible technically and promised to try it on his factory. So when we visited the industry they give us the information about the their idea in detail. Main person of the company is very friendly with us. Page | 16 Chapter 5 Block Diagram of the project 5. Block Diagram of the project Block diagram of complete project of the cell phone operated land rover is as shown in below figure. Fig. 5.1 block diagram of cell phone operated land rover 5.1) Description of block diagram In order to control the robot, you need to make a call to the cell phone attached to the robot (through headphone) from any phone, which sends DTMF tunes on pressing the numeric buttons. The cell phone in the robot is kept in 'auto answer' mode.( if the mobile does not have the auto answering facility ,receive the call by 'OK' key on the rover connected mobile and then made it in hands-free mode.) so after a ring, the cell phone accepts the call. Now you may press any button on your mobile to perform actions as listed in the table. The DTMF tones thus produced are received by the cell phone in the robot. These tones are fed to the circuit by headset of the cell phone. The MT8870 DTMF decoder decodes the received tone and sends the Page | 17 equivalent binary number to the microcontroller. According to the program in the microcontroller, the robot starts moving. When you press key '2' (binary equivalent 00000010) on your mobile phone, the microcontroller outputs '10001001'binary equivalent. Port pins P20, P23 and P27 are high. The high output at P27 of the microcontroller drives the motor driver (L293D). port pins P20 and P23 drive motors M1 and M2 in forward direction( as per table ).Similarly, motors M1 and M2 move for left turn, right turn, backward motion and stop condition as per table 5.1. Table 5.1 action performed corresponding to the keys pressed Page | 18 Chapter 6 Explanation of circuit Fig. 6.1 ckt diagram of cell phone operated land rover Output from 3.5 mm jack tip and ring is given to the 2nd pin of DTMF IC and to the ground respectively. Jack is connected to the mobile used in robot. When call is make to that cell phone and send dtmf to that phone then signal will converted into the binary signal. Then this binary signal is given to the 74ls04 inverter IC. Output of inverter IC is given to the micro controller AT-89S52’s PORT 1 and output is taken from the PORT0. The output is sets in program. Thin this output is given to the motor driver IC L293D. with this IC two geared dc motor is connected. According to the output from the IC L293D both motor will work. Page | 19 Chapter 7 Components detail 7.1) List of component used in project 1. Semiconductors IC1-MT8870 DTMF decoder IC2-ATMEL89S52 IC3-L293D motor drive IC4-74LS04 not gate 1N4007 rectifier diode 2. Resistors: 100-Kilo-ohm 330-kilo-ohm 10-kilo-ohm 3. Capacitors: 0.47uF ceramic disk 0.22pF ceramic disk 0.1uF ceramic disk 25v electrolytic capacitor 4. Miscellaneous: 3.57MHz crystal 12MHz crystal Page | 20 push to on switch M1, M2-6V, 50-rpm geared DC motor Batt-6V, 4.5Ah battery Robot’s mechanical body General purpose pcb 7.2.1 Details of Capacitor Figure 7.1 Capacitor A capacitor (formerly known as condenser) is a passive two-terminal electrical component used to store energy in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors separated by a dielectric (insulator); for example, one common construction consists of metal foils separated by a thin layer of insulating film. Capacitors are widely used as parts of electrical circuits in many common electrical devices. When there is a potential difference (voltage) across the conductors, a static electric field develops across the dielectric, causing positive charge to collect on one plate and negative charge Page | 21 on the other plate. Energy is stored in the electrostatic field. An ideal capacitor is characterized by a single constant value, capacitance, measured in farads. This is the ratio of the electric charge on each conductor to the potential difference between them. The capacitance is greatest when there is a narrow separation between large areas of conductor; hence capacitor conductors are often called "plates," referring to an early means of construction. In practice, the dielectric between the plates passes a small amount of leakage current and also has an electric field strength limit, resulting in a breakdown voltage, while the conductors and leads introduce an undesired inductance and resistance. Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass, in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune radios to particular frequencies and for many other purposes. The simplest capacitor consists of two parallel conductive plates separated by a dielectric with permittivity ε (such as air). The model may also be used to make qualitative predictions for other device geometries. The plates are considered to extend uniformly over an area A and a charge density ±ρ = ±Q/A exists on their surface. Assuming that the width of the plates is much greater than their separation d, the electric field near the centre of the device will be uniform with the magnitude E = ρ/ε. The voltage is defined as the line integral of the electric field between the plates. Solving this for C = Q/V reveals that capacitance increases with area and decreases with separation . The capacitance is therefore greatest in devices made from materials with a high permittivity, large plate area, and small distance between plates. We see that the maximum energy is a function of dielectric volume, permittivity, and dielectric strength per distance. So increasing the plate area while decreasing the separation between the plates while maintaining the same volume has no change on the amount of energy Page | 22 the capacitor can store. Care must be taken when increasing the plate separation so that the above assumption of the distance between plates being much smaller than the area of the plates is still valid for these equations to be accurate. Figure 7.2 Construction of capacitor -Ceramic capacitor A ceramic capacitor is a fixed value capacitor with the ceramic material acting as the dielectric. It is constructed of two or more alternating layers of ceramic and a metal layer acting as the electrodes. The composition of the ceramic material defines the electrical behavior and therefore the application of the capacitors, which are divided into two stability classes: Class 1 ceramic capacitors with high stability and low losses for resonant circuit application. Class 2 ceramic capacitors with high volumetric efficiency for buffer, by-pass and coupling applications. Page | 23 Fig. 7.3 fixed value ceramic capacitor Ceramic capacitors, especially the multilayer version (MLCC), are the most produced and used capacitors in electronic equipment with a produced quantity of approximately 1000 billion pieces per year. Ceramic capacitors of special shapes and styles are used as capacitors for RFI/EMI suppression, as feed-through capacitors, and in larger dimensions as power capacitors for transmitters. 7.2.2) Resistor A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element. The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's terminals to the intensity of current through the circuit is called resistance. This relation is represented by Ohm's law: Resistors are common elements of electrical networks and electronic circuits and are ubiquitous in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel- Page | 24 chrome). Resistors are also implemented within integrated circuits, particularly analog devices, and can also be integrated into hybrid and printed circuits. The electrical functionality of a resistor is specified by its resistance: common commercial resistors are manufactured over a range of more than nine orders of magnitude. When specifying that resistance in an electronic design, the required precision of the resistance may require attention to the manufacturing tolerance of the chosen resistor, according to its specific application. The temperature coefficient of the resistance may also be of concern in some precision applications. Practical resistors are also specified as having a maximum power rating which must exceed the anticipated power dissipation of that resistor in a particular circuit: this is mainly of concern in power electronics applications. Resistors with higher power ratings are physically larger and may require heat sinks. In a high-voltage circuit, attention must sometimes be paid to the rated maximum working voltage of the resistor. Practical resistors have a series inductance and a small parallel capacitance; these specifications can be important in high-frequency applications. In a low-noise amplifier or preamp, the noise characteristics of a resistor may be an issue. The unwanted inductance, excess noise, and temperature coefficient are mainly dependent on the technology used in manufacturing the resistor. They are not normally specified individually for a particular family of resistors manufactured using a particular technology. A family of discrete resistors is also characterized according to its form factor, that is, the size of the device and the position of its leads (or terminals) which is relevant in the practical manufacturing of circuits using them. Figure 7.4 Resistor Page | 25 7.2.3) Diode In electronics, a diode is a type of two-terminal electronic component with nonlinear resistance and conductance (i.e., a nonlinear current–voltage characteristic), distinguishing it from components such as two-terminal linear resistors which obey Ohm's law. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material connected to two electrical terminals. A vacuum tube diode (now rarely used except in some high-power technologies) is a vacuum tube with two electrodes: a plate and a cathode. The most common function of a diode is to allow an electric current to pass in one direction (called the diode's forward direction), while blocking current in the opposite direction (the reverse direction). Thus, the diode can be thought of as an electronic version of a check valve. This unidirectional behavior is called rectification, and is used to convert alternating current to direct current, and to extract modulation from radio signals in radio receivers—these diodes are forms of rectifiers. However, diodes can have more complicated behavior than this simple on–off action. Semiconductor diodes do not begin conducting electricity until a certain threshold voltage is present in the forward direction (a state in which the diode is said to be forward-biased). The voltage drop across a forward-biased diode varies only a little with the current, and is a function of temperature; this effect can be used as a temperature sensor or voltage reference. Semiconductor diodes' nonlinear current–voltage characteristic can be tailored by varying the semiconductor materials and introducing impurities into (doping) the materials. These are exploited in special purpose diodes that perform many different functions. For example, diodes are used to regulate voltage (Zener diodes), to protect circuits from high voltage surges (avalanche diodes), to electronically tune radio and TV receivers (varactor diodes), to generate radio frequency oscillations (tunnel diodes, Gunn diodes, IMPATT diodes), and to produce light (light emitting diodes). Tunnel diodes exhibit negative resistance, which makes them useful in some types of circuits. Diodes were the first semiconductor electronic devices. The discovery of crystals' rectifying abilities was made by German physicist Ferdinand Braun in 1874. The first Page | 26 semiconductor diodes, called cat's whisker diodes, developed around 1906, were made of mineral crystals such as galena. Today most diodes are made of silicon, but other semiconductors such as germanium are sometimes used. Figure 7.5 Diode 7.2.4) Crystal A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. This frequency is commonly used to keep track of time (as in quartz wristwatches), to provide a stable clock signal for digital integrated circuits, and to stabilize frequencies for radio transmitters and receivers. The most common type of piezoelectric resonator used is the quartz crystal, so oscillator circuits incorporating them became known as crystal oscillators, but other piezoelectric materials including polycrystalline ceramics are used in similar circuits. Here in this project we’ve used to different crystal which has different frequencies one is of 3.57 MHz and 12 MHz. Crystal having frequency of 3.57 MHz is connected with the DTMF IC and crystal having frequency of 12 MHz is connected with the micro controller . Page | 27 Figure 7.6 symbol of electric crystal Quartz crystals are manufactured for frequencies from a few tens of kilohertz to tens of megahertz. More than two billion crystals are manufactured annually. Most are used for consumer devices such as wristwatches, clocks, radios, computers, and cell phones. Quartz crystals are also found inside test and measurement equipment, such as counters, signal generators, and oscilloscopes. Page | 28 Figure 7.7 construction of the quartz crystal When a crystal of quartz is properly cut and mounted, it can be made to distort in an electric field by applying a voltage to an electrode near or on the crystal. This property is known as piezoelectricity. When the field is removed, the quartz will generate an electric field as it returns to its previous shape, and this can generate a voltage. The result is that a quartz crystal behaves like a circuit composed of an inductor, capacitor and resistor, with a precise resonant frequency. 7.2.5) Push button switch The "push-button" has been utilized in calculators, push-button telephones, kitchen appliances, and various other mechanical and electronic devices, home and commercial. In industrial and commercial applications, push buttons can be linked together by a mechanical linkage so that the act of pushing one button causes the other button to be released. In this way, a stop button can "force" a start button to be released. This method of linkage is used Page | 29 in simple manual operations in which the machine or process have no electrical circuits for control. Pushbuttons are often color-coded to associate them with their function so that the operator will not push the wrong button in error. Commonly used colors are red for stopping the machine or process and green for starting the machine or process. Red pushbuttons can also have large heads (called mushroom heads) for easy operation and to facilitate the stopping of a machine. These pushbuttons are called emergency stop buttons and are mandated by the electrical code in many jurisdictions for increased safety. This large mushroom shape can also be found in buttons for use with operators who need to wear gloves for their work and could not actuate a regular flush-mounted push button. As an aid for operators and users in industrial or commercial applications, a pilot light is commonly added to draw the attention of the user and to provide feedback if the button is pushed. Typically this light is included into the center of the pushbutton and a lens replaces the pushbutton hard center disk. The source of the energy to illuminate the light is not directly tied to the contacts on the back of the pushbutton but to the action the pushbutton controls. In this way a start button when pushed will cause the process or machine operation to be started and a secondary contact designed into the operation or process will close to turn on the pilot light and signify the action of pushing the button caused the resultant process or action to start. In popular culture, the phrase the button (sometimes capitalized) refers to a (usually fictional) button that a military or government leader could press to launch nuclear weapons. Figure 7.8 push button Page | 30 7.2.6)12v dc geared motor NR-DC-ECO is high quality low cost DC geared motor. It contains Brass gears and steel pinions to ensure longer life and better wear and tear properties. The gears are fixed on hardened steel spindles polished to a mirror finish. These spindles rotate between bronze plates which ensures silent running. The output shaft rotates in a sintered bushing. The whole assembly is covered with a plastic ring. All the bearings are permanently lubricated and therefore require no maintenance. The motor is screwed to the gear box from inside. Figure 7.9 geared dc motor Page | 31 The relationship between torque vs speed and current is linear as the load on a motor increases, Speed will decrease. As long as the motor is used in the area of high efficiency (as represented by the shaded area) long life and good performance can be expected. However, using the motor outside this range will result in high temperature rises and deterioration of motor parts. If voltage in continuous applied to a motor in a locked rotor condition, the motor will heat up and fail in a relatively short time. Therefore it is important that there is some form of protection against high temperature rises. A motor's basic rating point is slightly lower than its maximum efficiency point. Load torque can be determined by measuring the current drawn when the motor is attached to a machine whose actual load value is known. - Protection against overload and locked rotor:When the rotor is locked and voltage is applied to the motor terminals, the temperature of the motor windings will rise and eventually short-circuit. The time until a short-circuit condition appears differs per motor type.It is recommended that the motor is protected against such an overload by means of a fuse, current limiter or mechanical protection. Specification of geared dc motor: 1. Voltage: 12.0VDC 2. Output Speed: 50 RPM 3. No-Load output current: =< 50 mA 4. Rotation Output: CW / CCW 5. Noise: No Gear Noise 6. Stall output: Slip Gear, Broken Gear is no allowed Page | 32 7.2.7)6v battery 4.5Ah Figure 7.10 6v dc lead acid battery Nominal Voltage(V).....................................................................................6 volts(3cells in series) Nominal Capacity(AH) 20 hour Weight........................................................................................................................910g(2.00lbs.) Terminal Standard................................................................................................................Type T1 Application..........................................Electronic Toy-Cars.Emergency Lights, Rechargeable Flashlights, UPS, Fans 7.2.8) IC1-MT8870 DTMF decoder Features • Complete DTMF Receiver • Low power consumption • Internal gain setting amplifier • Adjustable guard time Page | 33 • Central office quality • Power-down mode • Inhibit mode • Backward compatible with MT8870C/MT8870C-1 Applications • Receiver system for British Telecom (BT) or CEPT Spec (MT8870D-1) • Paging systems • Repeater systems/mobile radio • Credit card systems • Remote control • Personal computers • Telephone answering machine Description The MT8870D/MT8870D-1 is a complete DTMF receiver integrating both the band -split filter and digital decoder functions. The filter section uses switched capacitor techniques for high and low group filters; the decoder uses digital counting techniques to detect and decode all 16 DTMF tone-pairs into a 4-bit code. External component count is minimized by on chip provision of a differential input amplifier, clock oscillator and latched three-state bus interface. Page | 34 Figure 7.11 DTMF IC having 18-pin DIP Pin Description 1. IN+ Non-Inverting Op-Amp (Input). 2. IN- Inverting Op-Amp (Input). 3. GS Gain Select. Gives access to output of front end differential amplifier for connection of feedback resistor. 4. V-Ref Reference Voltage (Output). Nominally VDD/2 is used to bias inputs at .5. INH mid-rail Inhibit (Input). Logic high inhibits the detection of tones representing characters A, B, C and D. This pin input is internally pulled down. 6. PWDN Power Down (Input). Active high. Powers down the device and inhibits the oscillator. This pin input is internally pulled down. 7. OSC1 Clock (Input). 8. OSC2 Clock (Output). A 3.579545 MHz crystal connected between pins OSC1 and OSC2 completes the internal oscillator circuit. 9. VSS Ground (Input). 0 V typical. Page | 35 10. TOE Three State Output Enable (Input). Logic high enables the outputs Q1-Q4. This pin is pulled up internally. 11-14. Q1-Q4 Three State Data (Output). When enabled by TOE, provide the code corresponding to the last valid tone-pair received (see Table 1). When TOE is logic low, the data outputs are high impedance. 15. StD Delayed Steering (Output).Presents a logic high when a received tone-pair has been registered and the output latch updated; returns to logic low when the voltage on St/GT falls below VTSt. 16. ESt Early Steering (Output). Presents a logic high once the digital algorithm has detected a valid tone pair (signal condition). Any momentary loss of signal condition will cause ESt to return to a logic low. 17. St/GT Steering Input/Guard time (Output) Bidirectional. A voltage greater than VTSt detected at St causes the device to register the detected tone pair and update the output latch. A voltage less than VTSt frees the device to accept a new tone pair. The GT output acts to reset the external steering time-constant; its state is a function of ESt and the voltage on St. 18. Vdd positive power supply typically +5v. 7.2.9) IC2-ATMEL89S52 Features • Compatible with MCS-51 Products • 8K Bytes of In-System Programmable (ISP) Flash Memory – Endurance: 10,000 Write/Erase Cycles • 4.0V to 5.5V Operating Range • Fully Static Operation: 0 Hz to 33 MHz • Three-level Program Memory Lock Page | 36 • 256 x 8-bit Internal RAM • 32 Programmable I/O Lines • Three 16-bit Timer/Counters • Eight Interrupt Sources • Full Duplex UART Serial Channel • Low-power Idle and Power-down Modes • Interrupt Recovery from Power-down Mode • Watchdog Timer • Dual Data Pointer • Power-off Flag • Fast Programming Time • Flexible ISP Programming (Byte and Page Mode) • Green (Pb/Halide-free) Packaging Option 1. Description The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the Indus-try-standard 80C51 instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory pro-grammar. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications. The AT89S52 provides the following standard features: 8K bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex serial port, Page | 37 on-chip oscillator, and clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue functioning. The Power-down mode saves the RAM con-tents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset. Figure 7.12 AT-89S52 DIP packaging Pin description VCC:- Supply voltage. GND:- Ground. Port 0 Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as high-impedance inputs. Port 0 can also be configured to be the multiplexed low-order address/data bus during accesses to external program and data memory. In this mode, P0 has internal pull-ups. Port 0 also Page | 38 receives the code bytes during Flash programming and outputs the code bytes during program verification. External pull-ups are required during program verification. Port 1 Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the inter-nal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups. In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX), respectively. Port 2 Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by the inter-nal pull-ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups. Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @ DPTR). In this application, Port 2 uses strong internal pull-ups when emitting 1s. During accesses to external data memory that uses 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register. Port 2 also receives the high-order address bits and some control signals during Flash programming and verification. Port 3 Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 3 output buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pull-ups. Port 3 receives some control signals for Flash programming and verification. RST :- Reset input. When high input s given to this pin controller will be reset. Page | 39 ALE :- Address Latch Enable (ALE) is an output pulse for latching the low byte of the address during accesses to external memory. PSEN :- Program Store Enable (PSEN) is the read strobe to external program memory. When the AT89S52 is executing code from external program memory, PSEN is activated twice each machine cycle. EA/VPP :- External Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program memory locations starting at 0000H up to FFFFH. XTAL1 :- Input to the inverting oscillator amplifier and input to the internal clock operating circuit. XTAL2 Output from the inverting oscillator amplifier. 7.2.10) IC3-L293D motor drive Feature -Wide Supply-Voltage Range: 4.5 V to 36 V -Separate Input-Logic Supply -Thermal Shutdown -High-Noise-Immunity Inputs -Output Current 1 A per Channel (600 mA for L293D) -Peak Output Current 2 A per Channel (1.2 A for L293D) -Output Clamp Diodes for Inductive Page | 40 Figure 7.13 16-pin DIP packaging L293D motor driver IC Description The L293 and L293D are quadruple high-current half-H drivers. The L293 is designed to provide Bidirectional drive currents of up to 1 A at voltages from 4.5 V to 36 V. The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V. Both devices are designed to drive inductive loads such as relays, solenoids, dc and bipolar stepping motors, as well as other high-current/high-voltage loads in positive-supply applications. All inputs are TTL compatible. Each output is a complete totem-pole drive circuit, with a Darlington transistor sink and a pseudo-Darlington source. Drivers are enabled in pairs, with drivers 1 and 2 enabled by 1,2EN and drivers 3 and 4 enabled by 3,4EN. When an enable input is high, the associated drivers are enabled and their outputs are active and in phase with their inputs. When the enable input is low, those drivers are disabled and their outputs are off and in the high-impedance state. With the proper data inputs, each pair of drivers forms a full-H (or bridge) reversible drive suitable for solenoid or motor applications. On the L293, external highspeed output clamp diodes should be used for inductive transient suppression. A VCC1 terminal, separate from VCC2, is provided for the logic inputs to minimize device power dissipation. Page | 41 7.2.11) IC4-74LS04 NOT gate This device contains six independent gates each of which performs the logic INVERT function. Figure 7.14 IC 74LS04 Page | 42 Chapter 8 Project design THREE STEP PROGRESS Page | 43 8.1) Programing part For programming of micro controller we use the software “Keil”. Which is one of the best software for the programing of the micro controller. Figure 8.1 screen of the keil software new open Keil Software development tools for the 8051 microcontroller family support every level of developer from the professional applications engineer to the student just learning about embedded software development. The industry-standard Keil C Compilers, Macro Assemblers, Debuggers, Real-time Kernels, and Single-board Computers support ALL 8051-compatible derivatives and help you get your projects completed on schedule. Keil offers following features for the programming of the micro controller: - ULINK USB Adapter for debugging and flash programming. - MCBx51 Evaluation Board for experimenting with various 8051 devices. - MCB900 Evaluation Board for experimenting with and testing Philips LPC900 devices. - MCBXC866 Evaluation Board for experimenting with and testing Infineon XC866 devices. Page | 44 Getting started µVision is a standard Windows application and started by clicking on the program icon. Create a Project File To create a new project file select from the µVision menu project – “New Project” This opens a standard Windows dialog that asks you for the new project file name. We can simply use the icon “Create New Folder” in this dialog to get a new empty folder. Then select this folder and enter the file name for the new project, i.e. project1. µVision creates a new project file with the name “PROJECT1.UV2” which contains a default target and file group name. You can see these names in the Project Workspace. Figure 8.2 create project environment Select a device When we create a new project µVision asks you to select a CPU for your project. The Select Device dialog box shows the µVision device database. Just select the microcontroller you use. We are Page | 45 using for our examples the ATMEL- AT89s52controller. This selection sets necessary tool options for the AT89S52 device and simplifies in this way the tool configuration. Figure 8.3 select a device Figure 8.4 write controller’s program in the source file Page | 46 After writing program in the source file we have to add program to the target folder. Different icons are used in the Project Workspace - Files page to show the attributes of files and file groups. These icons are explained below: Files that are translated and linked into the project are marked with an arrow in the file icon. Files that are excluded from the link run do not have the arrow. This is typical for document files. However you may exclude also source files when you disable Include in Target Build in the Properties dialog. Read only files are marked with a key. This is typical for files that are checked into a Software Version Control System, since the SVCS makes the local copy of such files read only. Files or file groups with specific options are marked with dots. Compilation After adding file to the target folder compilation take place. Figure 8.5 compilation of the program Page | 47 Debugging After compilation debugging of program take palce. In this step we can find differentdifferent output value on the output port for different input value on the input port. Figure 8.6 debugging of the program Create hex file After debugging we create hex file. This hex file will be load into the controller with the help of the loader. This hex file will be created into the same folder which was select for save the project. Then it is ready to load into the controller. Page | 48 Figure 8.7 creating hex file Program for the controller org 0000h mov p1,#0fh l1: mov a,p1 anl a,#0fh cjne a,#0dh,l2 mov p2,#89h ljmp l1 l2: cjne a,#0bh,l3 mov p2,#85h Page | 49 ljmp l1 l3: cjne a,#09h,l4 mov p2,#8ah ljmp l1 l4: cjne a,#07h,l5 mov p2,#86h ljmp l1 l5:cjne a,#0ah,l1 mov p2,#00h ljmp l1 h1:sjmp h1 end 8.2) Circuit part We have made our complete project on a special purpose PCB. I prepared the layout of both of these circuits using dip trace software. I learned dip trace software in my college. Then I installed the software from the internet and started working on it. Given below is the detailed description on dip trace software. 8.2.1 Dip trace Dip Trace is EDA software for creating schematic diagrams and printed circuit boards. The first version of Dip Trace was released in August, 2004. The latest version as of September 2011 is Dip Trace version 2.2. Interface has been translated to many languages and new Page | 50 language can be added by user. There are tutorials in English, Czech, Russian and Turkish. Starting from February 2011 Dip Trace is used as project publishing standard by Parallax. Modules Schematic Design Editor PCB Layout Editor Component Editor Pattern Editor Shape-Based Auto router 3D PCB Preview Freeware and Non-Profit versions A version of Dip Trace that is freely available with all the functionality of the full package except it is limited to 300 pins and 2 signal layers. Other sources Dip Trace at Seattle Robotics Society meeting Dip Trace at Nuts and Volts – October 2006 DIP TRACE Libraries by and for PICAXE microcontroller users Review at C Net External links Dip Trace official Website in English Novarm Ltd. Official Website in English 8.2.2) Hardware design The hardware design of the circuit of the project contains component as show nif the circuit diagram. Page | 51 8.3 Mechanical part of the project Mechanical part of the project contains the metal body, motors and wheels. On the metal body this all parts will be assemble. Figure 8.8 Wheels, motors, front wheel, motor clamps and base board Page | 52 Chapter9 Working of complete project 9. Working of complete project In order to control the robot, you need to make a call to the cell phone attached to the robot (through headphone) from any phone, which sends DTMF tunes on pressing the numeric buttons. The cell phone in the robot is kept in 'auto answer' mode.( if the mobile does not have the auto answering facility ,receive the call by 'OK' key on the rover connected mobile and then made it in hands-free mode.) so after a ring, the cell phone accepts the call. Now you may press any button on your mobile to perform actions as listed in the table. The DTMF tones thus produced are received by the cell phone in the robot. These tones are fed to the circuit by headset of the cell phone. The MT8870 DTMF decoder decodes the received tone and sends the equivalent binary number to the microcontroller. According to the program in the microcontroller, the robot starts moving. When you press key '2' (binary equivalent 00000010) on your mobile phone, the microcontroller outputs '10001001'binary equivalent. Port pins P20, P23 and P27 are high. The high output at P27 of the microcontroller drives the motor driver (L293D). port pins P20 and P23 drive motors M1 and M2 in forward direction( as per table ).Similarly, motors M1 and M2 move for left turn, right turn, backward motion and stop condition as per below figure. Figure 9.1 action performed corresponding to the keys pressed Page | 53 Chapter 10 Advantages 10.1 advantages & application APPLICATIONS: Scientific: Remote control vehicles have various Scientific uses including hazardous environments, working in the deep ocean , and space exploration. The majority of the probes to the other planets in our solar system have been remote control vehicles, although some of the more recent ones were partially autonomous. The sophistication of these devices has fueled greater debate on the need for manned space flight and exploration. The Voyager I spacecraft is the first craft of any kind to leave the solar system. The martian explorers Spirit and Opportunity have provided continuous data about the surface of Mars since January 3, 2004 Military and Law Enforcement: Military usage of remotely controlled military vehicles dates back to the first half of 20th century. Soviet Red Army used remotely controlled Teletanks during 1930s in the Winter War and early stage of World War II. There were also remotely controlled cutters and experimental remotely controlled planes in the Red Army. Search and Rescue: UAVs will likely play an increased role in search and rescue in the United States. This was demonstrated by the successful use of UAVs during the 2008 hurricanes that struck Louisiana and Texas. Recreation and Hobby: See Radio-controlled model. Small scale remote control vehicles have long been popular among hobbyists. These remote controlled vehicles span a wide range in terms of price and sophistication. There are many types of radio controlled vehicles. These include on-road cars, Page | 54 off-road trucks, boats, airplanes, and even helicopters. The ’robots’ now popular in television shows such as Robot Wars, are a recent extension of this hobby (these vehicles do not meet the classical definition of a robot; they are remotely controlled by a human). Radio-controlled submarine also exist. ADVANTAGES: 1. Wireless control 2. Surveillance System. 3. Vehicle Navigation with use of 3G technology. 4. Takes in use of the mobile technology which is almost available everywhere. 5. This wireless device has no limitation of range and can be controlled as far as network of cell phone FURTHER IMPROVEMENTS & FUTURE SCOPE : 1. IR Sensors: IR sensors can be used to automatically detect & avoid obstacles if the robot goes beyond line of sight. This avoids damage to the vehicle if we are maneuvering it from a distant place. 2. Password Protection: Project can be modified in order to password protect the robot so that it can be operated only if correct password is entered. Either cell phone should be password protected or necessary modification should be made in the assembly language code. This introduces conditioned access &increases security to a great extent. 3. Alarm Phone Dialer: By replacing DTMF Decoder IC CM8870 by a DTMF Transceiver IC’ CM8880, DTMF tones can be generated from the robot. So, a project called! Alarm Phone Dialer! Can be built which will generate necessary alarms for something that is desired to be monitored (usually by triggering a relay). For example, a high water alarm, low temperature alarm, opening of back Page | 55 window, garage door, etc. When the system is activated it will call a number of programmed numbers to let the user know the alarm has been activated. This would be great to get alerts of alarm conditions from home when user is at work. 4. Adding a Camera: If the current project is interfaced with a camera (e.g. a Webcam) robot can be driven beyond line-of-sight & range becomes practically unlimited as GSM networks have a very large range. Page | 56 CONCLUSION Conventionally, wireless-controlled robots use RF circuits, which have the drawbacks of limited working range, limited frequency range and limited control. Use of a mobile phone for robotic control can overcome these limitations. It provides the advantages of robust control, working range as large as the coverage area of the service provider, no interference with other controllers and up to twelve controls. Page | 57 BIBLIOGRAPHY Circuit reference taken from (1) www.electronicsforu.com, (2) www.google.com, (3) www.mycircuit9.com, (4) www.doctronics.com (5) www.wiekipedia.com Components application and configuration are from datasheet. Datasheet of components download from www.alldatasheet.com Reference from the book Page | 58