17-01-2011, 02:07 PM
sir,i am final year engineering student of entc branch i want detailed information on speed checker for highways using microcontroller
17-01-2011, 02:07 PM
sir,i am final year engineering student of entc branch i want detailed information on speed checker for highways using microcontroller
22-10-2012, 02:36 PM
c FOR HIGHWAYS
SPEED CHECKER.docx (Size: 2.09 MB / Downloads: 138) EMBEDDED SYSTEM: An embedded system is a special-purpose system in which the computer is completely encapsulated by or dedicated to the device or system it controls. Unlike a general-purpose computer, such as a personal computer, an embedded system performs one or a few predefined tasks, usually with very specific requirements. Since the system is dedicated to specific tasks, design engineers can optimize it, reducing the size and cost of the product. Embedded systems are often mass-produced, benefiting from economies of scale. Personal digital assistants (PDAs) or handheld computers are generally considered embedded devices because of the nature of their hardware design, even though they are more expandable in software terms. This line of definition continues to blur as devices expand. With the introduction of the OQO Model 2 with the Windows XP operating system and ports such as a USB port — both features usually belong to "general purpose computers", — the line of nomenclature blurs even more. Physically, embedded systems ranges from portable devices such as digital watches and MP3 players, to large stationary installations like traffic lights, factory controllers, or the systems controlling nuclear power plants. In terms of complexity embedded systems can range from very simple with a single microcontroller chip, to very complex with multiple units, peripherals and networks mounted inside a large chassis or enclosure. DESCRIPTION: A system designed to record and report on discrete activities within a process is called as Tracking System. In the same procedure we have developed a methodology of vehicle speed & direction system for robotics to control and achieve accurate direction speed for a class of non-linear systems in the presence of disturbances and parameter variations by using wireless communication technique. In this methodology we are using a micro controller, resulting in the state trajectory 'sliding' along path-varying slides on the surface. This idealized control law achieves perfect direction & speed however. The method is applied to the control of a two-link manipulator handling variable loads in a flexible manufacturing system environment. In our project we use IR sensors to detect the presence of a vehicle. According to this project, 2 IR sensors are placed apart with a fixed known distance. When ever IR rays are interrupted by a vehicle during first sensor the count up timer is started. When the other IR sensor senses the presence of vehicle, the count up timer is stopped. As the distance and time the IR receiver receives the IR signals is noted by microcontroller and from that we need to calculate speed. Here speed is calculated from the well known formula of speed which is distance/time. In this circuit we are using LCD display for indicating the speed. It is easy to set up and supports the required hardware. To design a vehicle that supports the newest technology available will be more expensive than boards that are already close to obsolete. A BRIEF HISTORY OF 8051 In 1981, Intel Corporation introduced an 8 bit microcontroller called 8051. This microcontroller had 128 bytes of RAM, 4K bytes of chip ROM, two timers, one serial port, and four ports all on a single chip. At the time it was also referred as “A SYSTEM ON A CHIP” AT89S52: 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 industry-standard 80C51 instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory pro-grammer. 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, 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 Internal RAM The 8052 have a bank of 256 bytes of internal RAM. The internal RAM is found on-chip. So it is the fastest Ram available. And also it is most flexible in terms of reading and writing. Internal Ram is volatile, so when 8051 is reset, this memory is cleared. 256 bytes of internal memory are subdivided. The first 32 bytes are divided into 4 register banks. Each bank contains 8 registers. Internal RAM also contains 256 bits, which are addressed from 20h to 2Fh. These bits are bit addressed i.e. each individual bit of a byte can be addressed by the user. They are numbered 00h to FFh. The user may make use of these variables with commands such as SETB and CLR. FILTER CAPACITOR Even though half wave & full wave rectifier give DC output, none of them provides a constant output voltage. For this we require to smoothen the waveform received from the rectifier. This can be done by using a capacitor at the output of the rectifier this capacitor is also called as “FILTER CAPACITOR” or “SMOOTHING CAPACITOR” or “RESERVOIR CAPACITOR”. Even after using this capacitor a small amount of ripple will remain. We place the Filter Capacitor at the output of the rectifier the capacitor will charge to the peak voltage during each half cycle then will discharge its stored energy slowly through the load while the rectified voltage drops to zero, thus trying to keep the voltage as constant as possible. |
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