In this project we will use IR sensors for detection and will attach a arm to clean the object. We will add autopath function in the project.
In project we will use two edge detector sensors to detect the wall. If wall will detected then our robo will move right or left according to edge detected
Our project is to be divided into few parts.
In this project we use smart logic and control system of embedded system by using microcontroller. In this project we use ic 89c51 as a main processor.. microcontroller sense the signal and drive the motor of the robotic vehicle. .
We will use H- bride IC l293d or H-bridge circuit using transistors.
We will use npn 548 and pnp 558 transistors.
We will use optocoupler in between micorntroller pins and h bridge circuit .
Power supply circuit.
In this project we use 9 volt battery to drive the vehicle. One 9 volt battery for the microcontroller circuit. Second 9 volt battery drive the motor driver circuit . Here in the project we one 5 volt regulator circuit. Output of the 9 volt dc is converted into 5 volt dc by using 7805 regulator circuit. Ic 7805 regulator converts the 9 volt dc into 5 volt dc with the help of the 5 volt regulator 7805.
In this project we use two small gear dc motor for drive the small robot. One motor for the back wheel and one motor for the front wheel. Back motor drive the both tyre at a time and front motor control the direction of the vehicle . Here we use powerful gear dc motor instead of stepper motor. Stepper is not suitable for the drive the vehicle. Stepper motor is suitable for positioning sensor but gear motor is suitable for the vehicle drive.
To make the robots mobile we need to have motors and the control circuitry that could control the motors. There are different kinds of motors available for different application.
1. DC motor
2. Stepper motor
3. Servo motor
89C2051 MICROCONTROLLER. Is a 20 pin version of 51 family,. Program written for this controller is same for the 8051 controller. In this controller there is total 15 input and output pins. For controlling the process control.
OPTOCOUPLER ( PC 817) In this project we use optocoupler to provide a electrical isolation between process control circuit and motor drive circuit. In this project we use separate supply for processor and control circuit. Pc 817 is 4 pin ic. In this coupler two pin is input and two pin is output.
CRYSTAL. In this project we use two crystal. One for the dtmf decoder and second with the microcontroller Main use of the crystal is to provide a external frequency for the internal oscillator. With the dtmf decoder we use crystal 3.58 Mhz and with the microcontroller we use 12 Mhz crystal.
DC MOTOR. We use slow speed dc motor to drive the movement of vehicle. In this project we use two dc motor. One for the drive the vehicle and second motor to change the direction of the vehicle.
H BRIDGE LOGIC: H bridge logic is basically provide a forward and reverse logic to the motor.
IC 74154 (1)
CRYSTAL ( 3.58 Mhz), (12 MhZ)
NPN TRANSISTOR BC 548 (4)
PNP TRANSISTOR BC 558(4)
4.7 K OHM (4)
1 K OHM (4)
22K OHM (2)
100 K (1)
10 mfd(1), .
DC MOTOR ( GEAR MOTOR) 2 MOTORíS
are the motors that are commonly found in the toys and the tape recorders. These
motors change the direction of rotation by changing the polarity. Most chips
can't pass enough current or voltage to spin a motor. Also, motors tend to be
electrically noisy (spikes) and can slam power back into the control lines when
the motor direction or speed is changed.
Specialized circuits (motor drivers) have been developed to supply motors with power and to isolate the other ICs from electrical problems. These circuits can be designed such that they can be completely separate boards, reusable from project to project.
A very popular circuit for driving DC motors (ordinary or gearhead) is called an H-bridge. It's called that because it looks like the capital letter 'H' on classic schematics. The great ability of an H-bridge circuit is that the motor can be driven forward or backward at any speed, optionally using a completely independent power source.
This circuit known as the H-bridge (named for its topological similarity to the letter "H") is commonly used to drive motors. In this circuit two of four transistors are selectively enabled to control current flow through a motor.
opposite pair of transistors (Transistor One and Transistor Three) is enabled, allowing current to flow through the motor. The other pair is disabled, and can be thought of as out of the circuit.
By determining which pair of transistors is enabled, current can be made to flow in either of the two directions through the motor. Because permanent-magnet motors reverse their direction of turn when the current flow is reversed, this circuit allows bidirectional control of the motor.
It should be clear that one would never want to enable Transistors One and Two or Transistors Three and Four simultaneously. This would cause current to flow from Power + to Power - through the transistors, and not the motors, at the maximum current-handling capacity of either the power supply or the transistors. This usually results in failure of the H-Bridge. To prevent the possibility of this failure, enable circuitry as depicted in Figure is typically used.
In this circuit, the internal inverters ensure that the vertical pairs of transistors are never enabled simultaneously. The Enable input determines whether or not the whole circuit is operational. If this input is false, then none of the transistors are enabled, and the motor is free to coast to a stop.
By turning on the Enable input and controlling the two Direction inputs, the motor can be made to turn in either direction.
Note that if both direction inputs are the same state (either true or false) and the circuit is enabled, both terminals will be brought to the same voltage (Power + or Power - , respectively). This operation will actively brake the motor, due to a property of motors known as back emf, in which a motor that is turning generates a voltage counter to its rotation. When both terminals of the motor are brought to the same electrical potential, the back emf causes resistance to the motor's rotation.
Stepper motors are special kind of heavy duty motors having 2 or 4 coils. The motors will be stepping each time when it get the pulse. As there are many coils in the motors we need to energize the coils in a specific sequence for the rotation of the motor. These motors are mostly used in heavy machines. The figure shown below consists of a 4 coil stepper motor and the arrow mark will rotate when the coils are energized in the sequence.
Unlike DC motors stepper motors can be turned accurately for the given degrees.
Servo motors unlike the stepper motor it has to be controlled by the timing signal. This motor has only one coil. It is mostly used in robots for its lightweight and low power consumption. The servo motors can also be accurately rotated by the making the control signal of the servo motor high for a specific time period. Actually the servo motor will be having 3 wires where 2 are for power supply and another one is for the control signal. Driving the servomotors is so simple that you need to make the control signal high for the specific amount of time. The width of the pulse determines the output position of the shaft
Detecting objects without whiskers doesnít require anything as sophisticated as machine vision. Some robots use RADAR or SONAR (sometimes called SODAR when used in air instead of water). An even simpler system is to use infrared light to illuminate the robotís path and determine when the light reflects off an object.The IR illuminators and detectors are readily available and inexpensive.
Infrared As Headlights
The infrared object detection system weíll build on the Bot is like a carís headlights in several respects. When the light from a carís headlights reflects off obstacles, your eyes detect the obstacles and your brain processes them and makes your body guide the car accordingly. We will be using infrared LEDs for headlights. They emit infrared, and in some cases, the infrared reflects off objects and bounces back in the direction of the detecter. The eyes of the Bot( mobile) are the infrared detectors. The infrared detectors send signals to the Microcontroller indicating whether or not they detect infrared reflected off an object. The brain of the Bot, the microcontroller makes decisions and operates the motors based on this sensor input.
More about IR - Detector
The IR detectors have built-in optical filters that allow very little light except the 980 nm infrared that we want to detect onto its internal photodiode sensor. The infrared detector also has an electronic filter that only allows signals around 38.5 kHz to pass through. In other words, the detector is only looking for infrared thatís flashing on and off 38,500 times per second.
Regenerative braking system
Introduction about project
In this project we will generate Electricity from Mechanical energy.
Most of us are
aware these days that the world-wide demand for electricity is actually growing
much faster than the population, and that the cost of building new electric
power plants and fueling them has become staggering. We have also heard that
power shortages and 'brown-outs' are becoming much more common. What many might
not realize, however, is that the world's pressing need for fresh water may well
become the most critical resource issue of the early 21st century.
In 1997, a United Nations freshwater resources assessment found that at least half a billion people then lived in countries with conditions of moderate to high "water stress". This figure is expected to rise to 3 billion by 2025, by which time the industrial use of water is expected to double. This sad situation is potentially desperate for developing countries with high water stress and low per-capita income. At the present time, nearly a billion people do not have access to clean drinking water. Countries in the more arid regions of the globe are especially vulnerable: in Israel, for example, the annual fresh water deficit exceeds 50 billion gallons, about 10% of their total yearly demand.
Even in the United States, shortage of water is an issue of major concern in large metropolitan areas from Los Angeles to Tampa. Much of California will be chronically short of water by 2010; the big cities of the Southwest could run out of water in 10 to 20 years; and Florida's reservoirs are nearing depletion levels while its water table is increasingly briny from seawater infiltration. Even cities in the Great Lakes region, which encompasses one-fifth of the world's surface fresh water, may very well face serious water shortages within 20 years
The World Resources Institute in Washington, DC recently reported that even with the implementation of stringent measures to control the global growth of demand and require that fresh water be used more efficiently, most particularly in the irrigation of farmland, new sources of supply will inevitably be needed. Historically, the desalinization of seawater has always been viewed as much too expensive to represent a reasonable solution to our water shortages. But with the advent of the StarDrive Electronic Dynamo developed by Archer Enterprises, this may no longer necessarily be true.
On an iron ring
twelve equal windings are winded in five layers of a 3-tenth wire and they can
be connected between them in three different manners, by two interruption hooks
and four plugs fixed on the basis.
According to the directions attached to the apparatus in the first connection (single-phase), the twelve windings are in series and the current is taken on two diametrically opposed points.
In the second connection (two-phase), the twelve windings form four sections of three series elements; then the four sections are connected in series: the first with the third and the second with the fourth. In this way we obtain two couples of free ends that will give us the two-phase system.
In the third connection, the twelve windings are still connected in series, and the current is taken from three points at 120 degrees one from the other (three-phase system with a delta-connection).
The ring is fixed vertically on a brass basis that supports also the inductor system formed by an electromagnet turning in the plane of the ring and stimulated with a battery of accumulators (8 V) or by a direct current with a maximum intensity of 5 A.
A heavy flywheel helps to make the electromagnet rotation regular. The connection is all-visible and the ends of the twelve sections are fixed to metallic gaskets, joined between them with mobile bridges, so that we can make different combinations from the one indicated above.
Electricity generation is the first process in the delivery of electricity to consumers. The other processes are electric power transmission and electricity distribution which are normally carried out by the electrical power industry.
2. LEDs 1.5v
3. Connecting wires
5. Drawing sheet
7. Soldering iron
8. Soldering wire
Big tyre 1feet diameter
One motor Ė AC Ė sewing machine
One stepper DC motor Ėto generate electricity
One 15mm pully
One steel rod
∑ Low cost
∑ Parts available in market
∑ extra cost for system
∑ need higher level engineering