CHAPTER 3

HARDWARE DESCRIPATRION 3.1Conveyor Belt3.2LM324 IC3.3LCD display3.4P89V51RD2 Microcontroller3.5Pulleys3.6IR sensor3.7D.C motor3.8Buzzer3.9Power supply3.10Component list

3.1 CONVEYOR BELT

Figure Conveyor Belt

Conveyer belt assembly is made by the using conveyer belt on pulley. This conveyer belt is run by the motor according to Microcontroller instruction. Also the empty bottles placed on the conveyer belt which movements controlled by the microcontroller.

Aconveyor beltis the carrying medium of abelt conveyor system(often shortened to belt conveyor). A belt conveyor system is one of many types ofconveyor systems. A belt conveyor system consists of two or morepulleys(sometimes referred to as drums), with an endless loop of carrying mediumthe conveyor beltthat rotates about them. One or both of the pulleys are powered, moving the belt and the material on the belt forward. The powered pulley is called the drive pulley while the unpowered pulley is called the idler pulley. There are two main industrial classes of belt conveyors; Those in generalmaterial handlingsuch as those moving boxes along inside a factory andbulk material handlingsuch as those used to transport large volumes of resources and agricultural materials, such asgrain,salt,coal,ore,sand,overburdenand more.

Today there are different types of conveyor belts that have been created for conveying different kinds of material available in PVC and rubber materials.Thebeltconsists of one or more layers of material. Many belts in general material handling have two layers. An under layer of material to provide linear strength and shape called a carcass and an over layer called the cover. The carcass is often a woven fabric having awarp&weft. The most common carcass materials are polyester, nylon and cotton. The cover is often various rubber or plastic compounds specified by use of the belt. Covers can be made from more exotic materials for unusual applications such as silicone for heat or gum rubber when traction is essential.

Material flowing over the belt may be weighed in transit using abelt weigher. Belts with regularly spaced partitions, known as elevator belts, are used for transporting loose materials up steep inclines. Belt Conveyors are used in self-unloading bulk freighters and in live bottom trucks. Belt conveyor technology is also used inconveyor transportsuch asmoving sidewalksor escalators, as well as on many manufacturingassembly lines. Stores often have conveyor belts at thecheck-out counterto move shopping items.Ski areasalso use conveyor belts totransport skiersup the hill.

Some of the major global conveyor belt service providers areTerra Nova Technologies,ThyssenKrupp,HESE Maschinenfabrik GmbHandTenova Takraf.

Belt conveyor systems

Conveyors are durable and reliable components used in automateddistributionand warehousing.In combination with computer controlled pallet handling equipment this allows for more efficientretail,wholesale, andmanufacturingdistribution. It is considered a labor saving system that allows large volumes to move rapidly through a process, allowing companies toshipor receive higher volumes with smaller storage space and with less laborexpense.

Rubber conveyor belts are commonly used to convey items with irregular bottom surfaces, small items that would fall in between rollers (e.g. asushi conveyor bar), or bags of product that would sag between rollers. Belt conveyors are generally fairly similar in construction consisting of a metal frame with rollers at either end of a flat metal bed. The belt is looped around each of the rollers and when one of the rollers is powered (by anelectrical motor) the belting slides across the solid metal frame bed, moving the product. In heavy use applications the beds which the belting is pulled over are replaced with rollers. The rollers allow weight to be conveyed as they reduce the amount of friction generated from the heavier loading on the belting. Belt conveyors can now be manufactured with curved sections which use tapered rollers and curved belting to convey products around a corner. Theseconveyor systemsare commonly used in postal sorting offices and airport baggage handling systems. A sandwich belt conveyor uses two conveyor belts, face-to-face, to firmly contain the item being carried, making steep incline and even vertical-lift runs achievable.

Belt conveyors are the most commonly used powered conveyors because they are the most versatile and the least expensive. Product is conveyed directly on the belt so both regular and irregular shaped objects, large or small, light and heavy, can be transported successfully. These conveyors should use only the highest quality premium belting products, which reduces belt stretch and results in less maintenance for tension adjustments. Belt conveyors can be used to transport product in a straight line or through changes in elevation or direction. In certain applications they can also be used for static accumulation or cartons.

BeltConveyor systemsat a Packing Depot

Baggage Handling BeltConveyor systems

Rollgangfor cartons and totes in a fashion distribution centre

Long belt conveyors

The longest beltconveyor systemin the world is inWestern Sahara. It is 98km (61mi) long, from thephosphateminesofBu Craato the coast south ofEl-Aaiun.

The longest conveyor system in an airport is theDubai International Airportbaggage handling system at 63km (39mi). It was installed bySiemensand commissioned in 2008, and has a combination of traditional belt conveyors and tray conveyors.

Boddingtons Bauxite Mine in Western Australia is officially recognized as having the world's longest and second-longest single belts with a 31-kilometre-long (19mi) belt feeding a 20km (12.5 miles) long belt. This system feeds bauxite through the difficult terrain of the Daring Ranges to the alumina refinery at Worsley. The longest single-belt international conveyor runs from Meghalaya in India to a cement factory at ChhatakBangladesh.It is about 17km long and conveyslimestoneandshaleat 960 tons/hour, from the quarry inIndiato the cement factory (7km long in India and 10km long in Bangladesh). The conveyor was engineered by AUMUND France and Larsen & Toubro. The conveyor is actuated by three synchronized drive units for a total power of about 1.8MW supplied by ABB (two drives at the head end in Bangladesh and one drive at the tail end in India). The conveyor belt was manufactured in 300-meter lengths on the Indian side and 500-meter lengths on the Bangladesh side, and was installed on-site byNILOS India. The idlers, or rollers, of the system are uniquein that they are designed to accommodate both horizontal and vertical curves along the terrain. Dedicated vehicles were designed for the maintenance of the conveyor, which is always at a minimum height of 5 meters (16ft) above the ground to avoid being flooded during monsoon periods.

Belt conveyor safety system

Conveyors used in industrial settings include tripping mechanisms such as trip cords along the length of the conveyor. This allows for workers to immediately shut down the conveyor when a problem arises. Warning alarms are included to notify employees that a conveyor is about to turn on. In the United States, theOccupational Safety and Health Administrationhave issued regulations for conveyor safety, as OSHA 1926.555.

3.2 LM324 IC

LM324 is a 14pin IC consisting of four independent operational amplifiers (op-amps) compensated in a single package. Op-amps are high gain electronic voltage amplifier with differential input and, usually, a single-ended output. The output voltage is many times higher than the voltage difference between input terminals of an op-amp.These op-amps are operated by a single power supply LM324 and need for a dual supply is eliminated. They can be used as amplifiers, comparators, oscillators, rectifiers etc. The conventional op-amp applications can be more easily implemented with LM324.

Pin Description:

Pin No.FunctionName

1Output of 1st comparatorOutput 1

2Inverting input of 1st comparatorInput 1-

3Non-inverting input of 1st comparatorInput 1+

4Supply voltage; 5V (up to 32V)Vcc

5Non-inverting input of 2nd comparatorInput 2+

6Inverting input of 2nd comparatorInput 2-

7Output of 2nd comparatorOutput 2

8Output of 3rd comparatorOutput 3

9Inverting input of 3rd comparatorInput 3-

10Non-inverting input of 3rd comparatorInput 3+

11Ground (0V)Ground

12Non-inverting input of 4th comparatorInput 4+

13Inverting input of 4th comparatorInput 4-

14Output of 4th comparatorOutput

Here This IC are used for to compare the liquid level in the bottle. By sensing the liquid level in the Bottle it generates the voltage output and gives to the controller. By using this IC we can check the presence of the liquid at the time of empty bottle and completely filled bottle. The output of this IC we can connect any I/o pin of the controller.

3.3LCD display

We are using JHD 162A LCD having 16 characters and 2 line structures. It is having 16 lines. In which 8 are data lines D0-D7, 3 control lines are there RS, WR, EN ,3 lines are for supply Vcc, Vee, GND and two lines LED+ and LED There are different LCDs having character per line ranges from 8 to max 64 and no. of lines generally 1 to 4.

Figure 5.27 Inter face of LCD Display to microcontroller

8081....8F

C0C1....CF

Address in LCD

COMMANDS FOR LCD DISPLAY

Hex codeCOMMAND

0x01HClear display screen

0x02HIncrement cursor(Shift cursor to right)

0x06HDisplay on, cursor blinking

0x0EHForce cursor to beginning of 1st line

0x80HForce cursor to beginning of 2nd line

0xC0H2nd line and 5X7 matrix

To set starting address; address of that location is sended as command. To send command RS pin is cleared. To send data RS pin is set. Than to Write to LCD WR pin is cleared and if we want to read LCD screen WR is set. So generally it is grounded. There is a RAM in LCD stores characters displayed on screen. LCD will active only when EN pin goes high to low.

3.4 MICROCONTRLLER:

GENERAL DESCRIPTION:The microcontroller is the heart of the system. The P89V51RD2 is an 80C51 microcontroller with 64 KB Flash and 1024 bytes of data RAM.

A key feature of the P89V51RD2 is its X2 mode option. The design engineer can choose to run the application with the conventional 80C51 clock rate (12 clocks per machine cycle) or select the X2 mode (6 clocks per machine cycle) to achieve twice the throughput at the same clock frequency.

The Flash program memory supports both parallel programming and in serial In-System Programming (ISP). Parallel programming mode offers gang-programming at high speed, reducing programming costs and time to market. ISP allows a device to be reprogrammed in the end product under software control. The capability to field/update the application firmware makes a wide range of applications possible. The P89V51RD2 is also In-Application Programmable (IAP), allowing the Flash program memory to be reconfigured even while the application is running.

FEATURES:80C51 Central Processing UnitV Operating voltage from 0 to 40 MHz64 KB of on-chip Flash program memory with ISP (In-System Programming) and IAP (In-Application Programming)Supports 12-clock (default) or 6-clock mode selection via software or ISPSPI (Serial Peripheral Interface) and enhanced UARTFour 8-bit I/O ports with three high-current Port 1 pins (16 mA each)Three 16-bit timers/countersProgrammable Watchdog timer (WDT)Eight interrupt sources with four priority levelsSecond DPTR registerTTL- and CMOS-compatible logic levels

BLOCK DIAGRAM:

Block diagram of P89V51RD2 microcontroller is shown in figure 5.2. This block diagram is same as that of the 80C51, but some advanced features are included in the P89V51RD2 which are given above.

Arithmetic and Logic UnitBPSWPCDPTR DPH DPLSFRRAMROMTo Port 0 &Port 2To Port 1 &Port 37AFigure 5.2 Block diagram of P89V51RD2 microcontroller

PIN DIAGRAM:

Figure 5.3 Pin diagram of P89V51RD2 microcontroller

PIN DESCRIPTION:

P89V51RD2 is a 40 pin microcontroller as shown in figure 5.3. Each pin has some specific function. Description of each pin is given below.Port 0(0.1-0.7) Pins 39-32: Port 0 is an 8-bit open drain bi-directional I/O port. Port 0 pins that have 1 are written to them float, and in this state can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external code and data memory. In this application, it uses strong internal pull-ups when transitioning to 1s. Port 0 also receives the code bytes during the external host mode programming, and outputs the code bytes during the external host mode verification. External pull-ups are required during program verification or as a general purpose I/O port.Port 1 1.0-1.7) Pins 1-8: Port 1 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 1 pins are pulled high by the internal pull-ups when 1s are written to them and can be used as inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. P1.5, P1.6, P1.7 have high current drive of 16 mA. Port 1 also receives the low-order address bytes during the external host mode programming and verification.T2: External count input to Timer/Counter 2 or Clock-out from Timer/Counter 2. Pin 1.0. Port 2 (2.0-2.7) Pins 21-28: Port 2 is an 8-bit bi-directional I/O port with internal pull-ups. Port 2 pins are pulled HIGH by the internal pull-ups when 1s are written to them and can be used as inputs in this state. As inputs, Port 2 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. Port 2 sends the high-order address byte during fetches from external program memory and during accesses to external Data Memory that use 16-bit address (MOVX @DPTR). In this application, it uses strong internal pull-ups when transitioning to 1s. Port 2 also receives some control signals and a partial of high-order address bits during the external host mode programming and verification.Port 3 (3.0-3.7) Pins 10-17: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins are pulled HIGH by the internal pull-ups when 1s are written to them and can be used as inputs in this state. As inputs, Port 3 pins that are externally pulled LOW will source current (IIL) because of the internal pull-ups. Port 3 also receives some control signals and a partial of high-order address bits during the external host mode programming and verification. Signal related to the port 1 are explained below.RXD: serial input portTXD: serial output portINT0: external interrupt 0 inputINT1: external interrupt 1 inputT0 : external count input to Timer/Counter 0T1 : external count input to Timer/Counter 1WR : external data memory write strobeRD : external data memory read strobe

PSEN (Program Store Enable) Active Low Pin 29: PSEN is the read strobe for external program memory. When the device is executing from internal program memory, PSEN is inactive (HIGH). When the device is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory. A forced HIGH-to-LOW input transition on the PSEN pin while the RST input is continually held HIGH for more than 10 machine cycles will cause the device to enter external host mode programming.Reset Pin 9: While the oscillator is running, a HIGH logic state on this pin for two machine cycles will reset the device. If the PSEN pin is driven by a HIGH-to-LOW input transition while the RST input pin is held HIGH, the device will enter the external host mode; otherwise the device will enter the normal operation mode. EA (External Access Enable) Active Low Pin 31: EA must be connected to VSS in order to enable the device to fetch code from the external program memory. EA must be strapped to VDD for internal program execution. However, Security lock level 4 will disable EA, and program execution is only possible from internal program memory. The EA pin can tolerate a high voltage of 12 V.ALE (Address Latch Enable) Pin 30: ALE is the output signal for latching the low byte of the address during an access to external memory.Crystal 1 Pin 19: Input to the inverting oscillator amplifier and input to the internal clock generator circuits. Crystal 2 Pin 18: Output from the inverting oscillator amplifier.Power Supply VDD Pin 40: It is connected to +5V power supply.Ground Pin 20: It is connected to ground.

MEMORY ORGANIZATION:The device has separate address spaces for program and data memoryFash program memory:There are two internal flash memory blocks in the device. Block 0 has 64 Kbytes and contains the users code. Block 1 contains the Philips-provided ISP/IAP routines and may be enabled such that it overlays the first 8 Kbytes of the user code memory. The 64 KB Block 0 is organized as 512 sectors; each sector consists of 128 bytes. Access to the IAP routines may be enabled by clearing the BSEL bit in the FCF register. However, caution must be taken when dynamically changing the BSEL bit. Since this will cause different physical memory to be mapped to the logical program address space, the user must avoid clearing the BSEL bit when executing user code within the address range 0000H to 1FFFH.Data RAM memory:The data RAM has 1024 bytes of internal memory. The device can also address up to 64 KB for external data memory.The device has four sections of internal data memory:1. The lower 128 bytes of RAM (00H to 7FH) are directly and indirectly addressable.2. The higher 128 bytes of RAM (80H to FFH) are indirectly addressable.3. The special function registers (80H to FFH) are directly addressable only.4. The expanded RAM of 768 bytes (00H to 2FFH) is indirectly addressable by the move external instruction (MOVX).Dual data pointers:The device has two 16-bit data pointers. The DPTR Select (DPS) bit in AUXR1 Determines which of the two data pointers is accessed. When DPS = 0, DPTR0 is selected; when DPS = 1, DPTR1 is selected. Quickly switching between the two data pointers can be accomplished by a single INC instruction on AUXR1 as shown below in figure 5.4.

Figure 5.4 Data pointer

TIMERS/COUNTERS 0 AND 1:

The two 16-bit Timer/Counter registers: Timer 0 and Timer 1 can be configured to operate either as timers or event counters in the Timer function, the register is incremented every machine cycle. Thus, one can think of it as counting machine cycles. Since a machine cycle consists of six oscillator periods, the count rate is 1/6 of the oscillator frequency. In the Counter function, the register is incremented in response to a 1-to-0 transition at its corresponding external input pin, T0 or T1. In this function, the external input is sampled once every machine cycle.The Timer or Counter function is selected by control bits C/T in the Special Function Register TMOD. These two Timer/Counters have four operating modes, which are selected by bit-pairs (M1, M0) in TMOD. Modes 0, 1, and 2 are the same for both Timers/Counters. Mode 3 is different. The four operating modes are described in the following text.TMOD Register:

Table 5TCON Register:

Table 5.Mode 0Putting either Timer into Mode 0 makes it look like an 8048 Timer, which is an 8-bit Counter with a fixed divide-by-32 prescaler. Figure 5.5 shows Mode 0 operation.In this mode, the Timer register is configured as a 13-bit register. As the count rolls over from all 1s to all 0s, it sets the Timer interrupt flag TFn. The count input is enabled to the Timer when TRn = 1 and either GATE = 0 or INTn = 1. (Setting GATE =1 allows the Timer to be controlled by external input INTn, to facilitate pulse width measurements). TRn is a control bit in the Special Function Register TCON. The GATE bit is in the TMOD register.

Figure 5.5 Timer modes 0The 13-bit register consists of all 8 bits of THn and the lower 5 bits of TLn. The upper 3 bits of TLn are indeterminate and should be ignored. Setting the run flag (TRn) does not clear the registers. Mode 0 operations are the same for Timer 0 and Timer 1 as shown in figure 4.7.Mode 1 Mode 1 is the same as Mode 0, except that all 16 bits of the timer register (THn and TLn) are used. See figure 5.6.

Figure 5.6 Timer modes 1

Mode 2

Mode 2 configures the Timer register as an 8-bit Counter (TLn) with automatic reloads, as shown in figure 5.7. Overflow from TLn not only sets TFn, but also reloads TLn with the contents of THn, which must be preset by software. The reload leaves THn unchanged. Mode 2 operation is the same for Timer 0 and Timer 1.

Figure 5.7 Timer modes 2

Mode 3

When timer 1 is in Mode 3 it is stopped (holds its count). The effect is the same as setting TR1 = 0. Timer 0 in Mode 3 establishes TL0 and TH0 as two separate 8-bit counters. The logic for Mode 3 and Timer 0 is shown in figure 5.8. TL0 uses the Timer 0 control bits: T0C/T, T0GATE, TR0, INT0, and TF0. TH0 is locked into a timer function (counting machine cycles) and takes over the use of TR1 and TF1 from Timer 1. Thus, TH0 now controls the Timer 1 interrupt. Mode 3 is provided for applications that require an extra 8-bit timer. With Timer 0 in Mode 3, the P89V51RD2 can look like it has an additional Timer.

Figure 5.8 Timer modes 3

Note: When Timer 0 is in Mode 3, Timer 1 can be turned on and off by switching it into and out of its own Mode 3. It can still be used by the serial port as a baud rate generator, or in any application not requiring an interrupt.

RESET:A system reset initializes the MCU and begins program execution at program memory location 0000H. The reset input for the device is the RST pin. In order to reset the device, a logic level high must be applied to the RST pin for at least two machine cycles (24 clocks), after the oscillator becomes stable. ALE, PSEN are weakly pulled high during reset. During reset, ALE and PSEN output a high level in order to perform a proper reset. This level must not be affected by external element. A system reset will not affect the 1 Kbytes of on-chip RAM while the device is running; however, the contents of the on-chip RAM during power up are indeterminate.

Power-on Reset:At initial power up, the port pins will be in a random state until the oscillator has started and the internal reset algorithm has weakly pulled all pins HIGH. Powering up the device without a valid reset could cause the MCU to start executing instructions from an indeterminate location. Such undefined states may inadvertently corrupt the code in the flash.When power is applied to the device, the RST pin must be held HIGH long enough for the oscillator to start up (usually several milliseconds for a low frequency crystal), in addition to two machine cycles for a valid power-on reset. An example of a method to extend the RST signal is to implement a RC circuit by connecting the RST pin VDD through a 10 mF capacitor and to VSS through an 8.2 kW resistor as shown in figure 5.9. Figure 5.9 Power on resetNote that if an RC circuit is being used, provisions should be made to ensure the VDD rise time does not exceed 1 millisecond and the oscillator start-up time does not exceed 10 milliseconds.Software resetThe software reset is executed by changing FCF[1] (SWR) from 0 to 1. A software reset will reset the program counter to address 0000H. All SFR registers will be set to their reset values, except FCF[1] (SWR), WDTC[2] (WDTS), and RAM data will not be altered.

SECURITY BIT:The Security Bit protects against software piracy and prevents the contents of the flash from being read by unauthorized parties in Parallel Programmer Mode. It also protects against code corruption resulting from accidental erasing and programming to the internal flash memory.

3.5PULLEYS: A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a cable or belt along its circumference. Pulleys are used in a variety of ways to lift loads, apply forces, and to transmit power. In nautical contexts, the assembly of wheel, axle, and supporting shell is referred to as a "block."A pulley may also be called a sheave or drum and may have a groove between two flanges around its circumference. The drive element of a pulley system can be a rope, cable, belt, or chain that runs over the pulley inside the groove.Hero of Alexandria identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another.

Block and tackle

Fig. Various ways of rigging a tackle.A set of pulleys assembled so that they rotate independently on the same axle form a block. Two blocks with a rope attached to one of the blocks and threaded through the two sets of pulleys form ablock and tackle.

Ablock and tackleis assembled so one block is attached to fixed mounting point and the other is attached to the moving load. Theideal mechanical advantageof the block and tackle is equal to the number of parts of the rope that support the moving block.

In the diagram on the right the ideal mechanical advantage of each of the block and tackle assembliesshown is as follows: Gun Tackle: 2 Luff Tackle: 3 Double Tackle: 4 Gyn Tackle: 5 Threefold purchase: 6

Rope and pulley systems

Fig. Pulley in oil derrick

A hoist is using the compound pulley system yielding an advantage of 4. The single fixed pulley is installed on thehoist (device). The two movable pulleys (joined together) are attached to thehook. One end of the rope is attached to the crane frame, another to the winch.

A rope and pulley system -- that is, ablock and tackle-- is characterized by the use of a single continuous rope to transmit a tension force around one or more pulleys to lift or move a loadthe rope may be a light line or a strong cable. This system is included in the list of simpleidentified by Renaissance scientists. If the rope and pulley system does not dissipate or store energy, then itsmechanical advantageis the number of parts of the rope that act on the load. This can be shown as follows.

Consider the set of pulleys that form the moving block and the parts of the rope that support this block. If there ispof these parts of the rope supporting the loadW,then a force balance on the moving block shows that the tension in each of the parts of the rope must be W/p.This means the input force on the rope isT=W/p.Thus, the block and tackle reduces the input force by the factorp.

A gun tackle has a single pulley in both the fixed and moving blocks with two rope parts supporting the loadW.

Separation of the pulleys is in the gun tackle show the force balance that results in a rope tension ofW/2.

A double tackle has two pulleys in both the fixed and moving blocks with four rope parts are supporting the loadW.

Separation of the pulleys is in the double tackle show the force balance that results in a rope tension ofW/4.

How it worksThe simplest theory of operation for a pulley system assumes that the pulleys and lines are weightless, and that there is no energy loss due to friction. It is also assumed that the lines do not stretch.

In equilibrium, the forces on the moving block must sum to zero. In addition the tension in the rope must be the same for each of its parts. This means that the two parts of the rope supporting the moving block must each support half the load.

Fig. Fixed pulley

Diagram 1: The loadF on the moving pulley is balanced by the tension in two parts of the rope supporting the pulley.

Fig. Movable pulley

Diagram 2: A movable pulley lifting the loadW is supported by two rope parts with tensionW/2.

These are different types of pulley systems: Fixed:Afixedpulley has an axle mounted in bearings attached to a supporting structure. A fixed pulley changes the direction of the force on a rope or belt that moves along its circumference. Mechanical advantage is gained by combining a fixed pulley with a movable pulley or another fixed pulley of a different diameter. Movable:Amovablepulley has an axle in a movable block. A single movable pulley is supported by two parts of the same rope and has a mechanical advantage of two. Compound:A combination of fixed and a movable pulleys are forms ablock and tackle. Ablock and tacklecan have several pulleys mounted on the fixed and moving axles, further increasing the mechanical advantage.

Diagram 3: The gun tackle "rove to advantage" has the rope attached to the moving pulley. The tension in the rope isW/3yielding an advantage of three.

Diagram 3a: The Luff tackle adds a fixed pulley "rove to disadvantage." The tension in the rope remainsW/3yielding an advantage of three.

The mechanical advantage of the gun tackle can be increased by interchanging the fixed and moving blocks so the rope is attached to the moving block and the rope is pulled in the direction of the lifted load. In this case theblock and tackleis said to be "rove to advantage."Diagram 3 shows that now three rope parts support the loadWwhich means the tension in the rope isW/3. Thus, the mechanical advantage is three.

By adding a pulley to the fixed block of a gun tackle the direction of the pulling force is reversed though the mechanical advantage remains the same, Diagram 3a. This is an example of the Luff tackle.

Free body diagramsThemechanical advantageof a pulley system can be analyzed usingfree body diagramswhich balance thetension forcein the rope with theforce of gravityon the load. In an ideal system, the mass less and frictionless pulleys do not dissipate energy and allow for a change of direction of a rope that does not stretch or wear. In this case, a force balance on a free body that includes the load,W, andnsupporting sections of a rope with tensionT, yields:

The ratio of the load to the input tension force is the mechanical advantageMAof the pulley system,

Thus, the mechanical advantage of the system is equal to the number of sections of rope supporting the load.

Belt and pulley systems

Fig. Flat belt on a belt pulley

Fig. Belt and pulley system

Fig. Cone pulley driven from above by a line shaft

A belt and pulley system is characterized by two or more pulleys in common to a belt. This allows formechanical power,torque, andspeedto be transmitted across axles. If the pulleys are of differing diameters, a mechanical advantage is realized.

A belt drive is analogous to that of achain drive, however a belt sheave may be smooth (devoid of discrete interlocking members as would be found on a chain sprocket,spur gear, or timing belt) so that the mechanical advantage is approximately given by the ratio of the pitch diameter of the sheaves only, not fixed exactly by the ratio of teeth as with gears and sprockets.

In the case of a drum-style pulley, without a groove or flanges, the pulley often is slightly convex to keep theflat beltcentred. It is sometimes referred to as a crowned pulley. Though once widely used on factoryline shafts, this type of pulley is still found driving the rotating brush in uprightvacuum cleaners, inbelt sandersand band saws.Agriculturaltractorsbuilt up to the early 1950s generally had a belt pulley for a flat belt (which is whatBelt Pulleymagazine was named after). It has been replaced by other mechanisms with more flexibility in methods of use, such as power take-offandhydraulics.

Just as the diameters ofgears(and, correspondingly, their number of teeth) determine agear ratioand thus the speed increases or reductions and the mechanical advantagethat they can deliver, the diameters of pulleys determine those same factors.Cone pulleysand step pulleys (which operate on the same principle, although the names tend to be applied to flat belt versions and V belt versions, respectively) are a way to provide multiple drive ratios in a belt-and-pulley system that can be shifted as needed, just as atransmissionprovides this function with agear trainthat can be shifted. V belt step pulleys are the most common way thatdrill pressesdeliver a range of spindle speeds.

3.6IR SENSOR: GENERAL DESCRIPTION:IR Proximity SensorThis sensor can be used to measure the speed of object moving at a very high speed, like in industry.

Object Detection using IR light

It is the same principle in ALL Infra-Red proximity sensors. The basic idea is to send infra red light through IR-LEDs, which is then reflected by any object in front of the sensor.

One of the most useful sensors finds its application while detecting object/hurdles, edges of surface etc. With a long range of 20 cm, TLL interface and ambient light protection makes it easy and reliable to use.

Features:Range: 20 cmAmbient light protectionEasy interface with microcontrollerOn board LED to indicate logic signalsIR modules have three pins which are connected to 8051 as Ground pin connected to any GND pin of board. +5V provided by the 8051 board. Connect output pin of IR module to any i/o pin of 8051 board by using its pin header.Here we have use the IR proximity sensor to check the bottle detection at the particular place where the liquid filling system is planted. If the IR sensor detect the bottle on the conveyer belt than the IR sensor gives it output to the controller and controller stops the movement of the bottle.

3.7 DC MOTOR:DC Motors convert electrical energy (voltage or power source) to mechanical energy (produce rotational motion).They run on direct current.The Dc motor works on the principle of Lorentz force which states that when a wire carrying current is placed in a region having magnetic field, than the wire experiences a force.This Lorentz force provides a torque to the coil to rotate.

A commonly used DC Motor is shown in the image above.The above image shows the brushes of the DC motor which helps the motor to take input current to the coil.The brushes always remain connected with any two commutators and supplying the input current to the coil while it is rotating.Closer LookYou can have a closer look as to how the electrical coil is arranged in the permanent magnet.

When DC current is passed through the coil, it works as electromagnet. As you can see the iron plates attached around the coil helps the coil to keep in center and movable. Permanent magnet attracts these three iron plates equally; resultantly it stays in the center of the permanent magnet. There are three commutators shown in the image. Each one is directly connected with the coil to supply the current in. The permanent magnet is cascaded in the body of the motor. The permanent magnet is cascaded in the body of the motor. The coil working as electromagnet moves in the magnetic field of this magnet. A motor speed control IC is used to control the rotating speed of compact DC motor. The IC integrated in the circuit has an inbuilt reverse voltage protection circuit.

Working: As we have discussed, DC motor work on Lorentz force concept. When we pass the input DC current to the coil through the brushes, it directly goes to the coil inside the motor body. This makes coil to work as an electromagnet. Magnetic fields of both magnets interact with each other that results in a force which in turn produces the necessary torque required to move the coil. This torque drives the coil to move round and a shaft attached with the coil moves too.

How Geared DC Motor worksGeared DC motors can be defined as an extension of DC motor. A geared DC Motor has a gear assembly attached to the motor. The speed of motor is counted in terms of rotations of the shaft per minute and is termed as RPM .The gear assembly helps in increasing the torque and reducing the speed. Using the correct combination of gears in a gear motor, its speed can be reduced to any desirable figure. This concept where gears reduce the speed of the vehicle but increase its torque is known as gear reduction. This Insight will explore all the minor and major details that make the gear head and hence the working of geared DC motor.External Structure: At the first sight, the external structure of a DC geared motor looks as a straight expansion over the simple DC ones. Also, an internally threaded hole is there on the shaft to allow attachments or extensions such as wheel to be attached to the motor. The outer body of the gear head is made of high density plastic but it is quite easy to open as only screws are used to attach the outer and the inner structure. The major reason behind this could be to lubricate gear head from time to time. The plastic body has a threading through which nut can be easily mounted and vice versa from the gear head.

Rear view The rear view of the geared motor is similar to the DC motor and it has two wires soldered to it.Internal Structure On opening the outer plastic casing of the gear head, gear assemblies on the top as well as on bottom part of the gear head are visible. These gear assemblies are highly lubricated with grease so as to avoid any sort of wear and tear due to frictional forces. Shown below is the top part of the gear head. It is connected to rotating shaft and has one gear that allows the rotation. A strong circular imprint shows the presence of the gear that rotates the gear at the upper portion.

Connection of the shaft with the gear is shown in the image under. The cap that accommodates the gear has an arc cut from its side to avoid frictional resistance forces with the bottom gear assembly.

The bottom houses the gear mechanism which is connected to the DC motor through screws. This mechanism rotates the gear at the top which is connected to the rotating shaft.

Bottom Gear Assembly A closer look at the bottom gear assembly shows the structure and connection with other gears.

Gear assemblys association with the motor (bottom gear assembly) can be understood with the help of the image shown below. The gear assembly is set up on two metallic cylinders whose working can be called as similar to that of an axle. A total of three gears combine on these two cylinders to form the bottom gear assembly out of which two gears share the same axle while one gear comes in between them and takes a separate axle. The gears are basically in form of a small sprocket but since they are not connected by a chain, they can be termed as duplex gears in terms of a second cog arrangement coaxially over the base. Among the three gears, two are exactly same while the third one is bigger in terms of the number of teeth at the upper layer of the duplex gear. The third gear is connected to the gear at the upper portion of the gear head. The manner in which they are located near the upper part of the gear head can be seen through the image shown. The combination of bottom gear assembly with the upper one can be seen down under.

After the gear assembly is removed, gear heads connection to the DC motor and its gear can be easily seen. The machine has a smaller gear in comparison to the gear heads gear assembly.Working of the DC Geared Motor The DC motor works over a fair range of voltage. The higher the input voltage more is the RPM (rotations per minute) of the motor. For example, if the motor works in the range of 6-12V, it will have the least RPM at 6V and maximum at 12 V. In terms of voltage, we can put the equation as: RPM= K1 * V, where, K1= induced voltage constant V=voltage applied The working of the gears is very interesting to know. It can be explained by the principle of conservation of angular momentum. The gear having smaller radius will cover more RPM than the one with larger radius. However, the larger gear will give more torque to the smaller gear than vice versa. The comparison of angular velocity between input gear (the one that transfers energy) to output gear gives the gear ratio. When multiple gears are connected together, conservation of energy is also followed. The direction in which the other gear rotates is always the opposite of the gear adjacent to it. In any DC motor, RPM and torque are inversely proportional. Hence the gear having more torque will provide a lesser RPM and converse. In a geared DC motor, the concept of pulse width modulation is applied. The equations detailing the working and torque transfer of gears are shown below:

In a geared DC motor, the gear connecting the motor and the gear head is quite small, hence it transfers more speed to the larger teeth part of the gear head and makes it rotate. The larger part of the gear further turns the smaller duplex part. The small duplex part receives the torque but not the speed from its predecessor which it transfers to larger part of other gear and so on. The third gears duplex part has more teeth than others and hence it transfers more torque to the gear that is connected to the shaft.

3.8 BUZZER

Fig. Buzzer Buzzer is used for alert the people who are going on the Bridge for crossing the railway.

ElectromechanicalThe first electric buzzer was invented in 1831 byJoseph Henry. They were mainly used in early doorbells until they were phased out in the early 1930's in favor of musical chimes, which had a softer tone.

PiezoelectricPiezoelectricbuzzers, or piezo buzzers, as they are sometimes called, were invented by Japanese manufacturers and fitted into a wide array of products during the 1970s to 1980s. This advancement mainly came about because of cooperative efforts by Japanese manufacturing companies. In 1951, they established the Barium Titanate Application Research Committee, which allowed the companies to be "competitively cooperative" and bring about several piezoelectric innovations and inventions. Type of BuzzersElectromechanicalEarly devices were based on an electromechanical system identical to anelectric bellwithout the metal gong. Similarly, are laymay be connected to interrupt its own actuatingcurrent, causing thecontactsto buzz. Often these units were anchored to a wall or ceiling to use it as a sounding board. The word "buzzer" comes from the rasping noise that electromechanical buzzers made.

MechanicalAjoy buzzeris an example of a purely mechanical buzzer. They require a driver.

Piezoelectric

Piezoelectric disk beeperA piezoelectric element may be driven by anoscillatingelectronic circuit or other audio signalsource, driven with apiezoelectric audio amplifier. Sounds commonly used to indicate that a button has been pressed are a click, a ring or a beep.

Modern ApplicationsWhile technological advancements have caused buzzers to be impractical and undesirable, there are still instances in which buzzers and similar circuits may be used. Present day applications include:

Novelty uses Educational purposes Annunciator panels Electronic metronomes Game show lock-out device Microwave ovens and other household appliances Sporting events such as basketball games Electrical alarms Joy buzzer- a mechanical buzzer used for pranks

3.9 POWER SUPPLY

To active any device voltage source is required. For different device different voltage source is required. In our project we use +5V and +3.3V DC power supplies. The +5V is required for controller unit. For sensor unit +5V and +3.3V is also required. To get +5V we use 7805 voltage regulator IC. To get +3.3V we use LM117 voltage regulator IC. Refer figure.

Figure Power supply

3.10 Component List

SR. NO.NAME OF COMPONENTNO. OF COMPONENT USED

1.Conveyor Belt1

2.IR Sensor2

3.LM324 IC1

4.Microcontroller Board1

5.Pulleys2

6.Shaft2

7.DC Motor2

8.BoxesAs per requirement

9.Buzzers1