ROBOT CONTROLLER( H- bridge)

REMOTE UPPER PART1a) CONTAINS 4 RELAYS ,,EACH RELAY

CONSISITS OF 5 PINS . 2 PINS ARE NC (normally closed) AND NO (normally open) ,while 3 pins on the other side denote commom or change over ( at center) and the two pins are of coil .

. IC is also placed which is used for giving output to the switches only high or low and converting low current to high current as we learn in case of transistors

REMOTE LOWER PART1b) CONSISTS OF IC LOWER PART CONNECTED

TO THE 4 SWITCHES.

4 SWITCHES CONTAINS THERE OWN RESISTOR TO RESIST THE HIGH CURRENT FLOW.

2) This remote is handmade H-bridge remote to know about the internal procedure inside each switch, but know in markets SPST switches are available in which all type of transistor ,resistors,diodes etc are present internally.

ALL 4 COLOURS OF WIRES ARE COMING FROM RELAY COMMON (CENTRE ) PART ,WHICH FURTHER MAKE CONNECTION WITH THE MOTOR OF THE ROBOT.

ROBOTICS• RELAYS-A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching

mechanism mechanically, but other operating principles are also used.• When an electric current is passed through the coil it generates a magnetic field that attracts the armature, and

the consequent movement of the movable contact(s) either makes or breaks (depending upon construction) a connection with a fixed contact. When the current to the coil is switched off, the armature is returned by a force,

• When the coil is energized with direct current, a diode is often placed across the coil to dissipate the energy from the collapsing magnetic field at deactivation,

• COM = Common, always connect to this, it is the moving part of the switch.• NC = Normally Closed, COM is connected to this when the relay coil is off.• NO = Normally Open, COM is connected to this when the relay coil is on.• Connect to COM and NO if you want the switched circuit to be on when the relay coil is on.• Connect to COM and NC if you want the switched circuit to be on when the relay coil is off.• SPST – Single Pole Single Throw. These have two terminals which can be connected or disconnected. Including two for the coil, such a

relay has four terminals in total. It is ambiguous whether the pole is normally open or normally closed. The terminology "SPNO" and "SPNC" is sometimes used to resolve the ambiguity.

• SPDT – Single Pole Double Throw. A common terminal connects to either of two others. Including two for the coil, such a relay has five terminals in total.

• DPST – Double Pole Single Throw. These have two pairs of terminals. Equivalent to two SPST switches or relays actuated by a single coil. Including two for the coil, such a relay has six terminals in total. The poles may be Form A or Form B (or one of each).

• DPDT – Double Pole Double Throw. These have two rows of change-over terminals. Equivalent to two SPDT switches or relays actuated by a single coil. Such a relay has eight terminals, including the coil.

1) RELAYS

IMAGES OF RELAY

. NO AND NC ARE NAMED SO ,BECAUSE OF THE POSITION OF THE PIN WITH RESPECT TO COIL

Protection of a relay using diode

• Transistors and ICs must be protected from the brief high voltage produced when a relay coil is switched off. The diagram shows how a signal diode (eg 1N4148) is connected 'backwards' across the relay coil to provide this protection.

• Current flowing through a relay coil creates a magnetic field which collapses suddenly when the current is switched off. The sudden collapse of the magnetic field induces a brief high voltage across the relay coil which is very likely to damage transistors and ICs. The protection diode allows the induced voltage to drive a brief current through the coil (and diode) so the magnetic field dies away quickly rather than instantly. This prevents the induced voltage becoming high enough to cause damage to transistors and ICs.

IC’s •Integrated circuits, also called "chips", are electronic circuits where all the components (transistors, diodes, resistors and capacitors) has been manufactured in the surface of a thin substrate of semiconductor material.

Different types of ic’s having different types of gates are shown above.

• Types of Ics:

• Integrated circuits can be classified into three types they are, (1).Analog. (2).Digital. (3).Mixed signal. Analog ICs, such as sensors, power management circuits, and operational amplifiers, work by processing continuous signals. They perform functions like amplification, active filtering, de modulation, mixing, etc

• Digital integrated circuits can contain anything from one to millions of logic gates, multiplexers(A device that can interleave two or more activities), and other circuits in a few square millimeters. The small size of these circuits allows high speed, low power dissipation, and reduced manufacturing cost compared with board-level integration. ICs can also combine analog and digital circuits on a single chip to create functions such as Ac/Dc converters and Dc/Ac converters. Such circuits offer smaller size and lower cost.

• An application-specific integrated circuit (ASIC) is an integrated circuit customized for a particular use, rather than intended for general-purpose use. For example, a chip designed solely to run a cell phone is an ASIC. As feature sizes have shrunk and design tools improved over the years, the maximum complexity (and hence functionality) possible in an ASIC has grown from 5,000 gates to over 100 million. Modern ASICs often include memory blocks including ROM, RAM, Flash and other large building blocks.