Training Workshop Projects

Automatic drilling machine. In this project we will use four motors. First of all we try to use electronics circuit in this project. As its impossible for us to implement it using electronics circuit. So we tried it with special motors. We are trying it to buy from Delhi – motors with rpm control. Now in this project we will use one motor to move job bed forward and backward. Another motor will move drilling from on plastic pillars frames.

It will move on gear assembly to hold the frame at any stage.

In this project we will make mechanism to control machine. Our job bed will be placed on moving bed. When we will press switch then our frame will move forward and reverse. After moving frame, again job bed will move 45 degree. This process will continue. This process will continue for three times. We will use 8051 series microcontroller to control all functions. There will be two switches – One for reset and one for start function.

There will be transistorized circuit to make relays working.

Crane control,lift control. Robotic arm is part of the mechatronic industry todays fast growing industry. In this project we will three stepper motors for controlling purpose. But we will try to control three functions with two motors. We know it will not  a easy task for meachnical industry because we will have to control the stepper motors using microcontrollers programming. In this project we will control the stepper motors with microcontroller. We will use 89c051 for this purpose because one of our friend have this ic’s programming kit and he will help us in programming.First of all we will make the PCB- printed circuit board  or will design it from outer sources. Then we will soder components on PCB. In this project we will make 5volt power supply for microcontroller circuit.

First of all we will design the jaws of robotic arm. It will be of following shape

Jaws will be metallic. They will be made of sheet metal.

 ARM: arm will be made up of wood materi

Stepper motor: stepper motor have five wires . One for common supplies another four for winding purpose. By giving different signal to each we will control the stepper motor.

The wires from the Logic PCB connector to the stepper motor in a TM100 Disk Drive are as follows

This kind of motor has four coils which, when energised in the correct sequence, cause the permanent magnet attached to the shaft to rotate.

There are two basic step sequences. After step 4, the sequence is repeated from step 1 again.

Reversing the order of the steps in a sequence will reverse the direction of rotation.

a. Single-Coil Excitation – Each successive coil is energised in turn.

This sequence produces the smoothest movement and consumes least power.

Inside a Stepper Motor
The stepper motors we are concerned with are those taken out of old 5 ¼” floppy disk drives. Some of the comments below may therefore not apply in all cases…The simplest way to think of a stepper motor is a bar magnet and four coils.

When current flows though coil “A” the magnet is attracted and moves one step to the right. Coil A is then turned off and coil “B” turned on. The magnet moves another step to the right. Coil “B” is then turned off and coil “C” turned on. The magnet moves another step to the right and so on…

A similar process occurs inside the stepper motor, but the ‘magnet’ is cylidrical and rotates inside the coils.

In order to make a stepper motor rotate you must turn on each coil in the correct sequence. The motor will continue to rotate as long as you continue the sequence. A typical code sequence would be: until count > 50;

NOTE1: The “delay” is needed provide enough time for the magnetic field inside the coils to build up and the magnet to move. Without the ‘delay’, the coils will switch on and off so fast that the magnet will not get a chance to be attracted and it will not move.

NOTE2: To reverse the direction, simply reverse the output order.
The Coil Switch-on Sequence
The stepper motor in a 5 ¼” floppy drive (the one that moves the head back and forth over the disk – NOT the one that spins the disk) has FIVE wires coming out of it. If you are lucky they will be coloured Brown, Yellow, Red, Blue and White. (Many of the ones I’ve looked at have five brown wires!)

The ‘four’ coils described above are actually arranged as two 150 ohm coils with centre taps. The centre taps are lines “1” and “2” in Figure 1.1. This line is generally called the “common”.

Measuring the resistance between each of the wires coming out of the motor produces the following readings: One of the five wires is the ‘common’. You can easily identify the common with a multimeter. It will be the one that reads 75 ohms between it and all the other four lines in turn. The other four are impossible to identify using a multimeter. You will need to use an interface and connect it to a computer for the next step. (You could just use wires from a 12 volt battery if you wanted.)

Using the Demonstration Interface to Drive a Stepper Motor
(For details about the Demonstration Interface see: robokit.html)

• Connect a 12 volt DC supply to the demonstration interface (in place of the 9 volt battery).

• Solder the ‘common’ lead to the positive line on the Demonstration Interface.

• Solder each of the other four wires to the points where the resistor connects to a line from the ULN2803. (Keep the wires in order from the common wire and solder them to data lines 0, 1, 2, and 3.)

• Connect the interface to a computer and send ‘out’ commands of 1,2,4 and 8. The motor should ‘step’ in a clockwise, or anti-clockwise direction. – If it ‘jerks’ as it tries to change direction, or simply ‘shudders’ you will need to experiment with other control sequences.

Hopefully your motor moved in a consistent direction. Now you need to write code as outlined above and try for complete rotations

Components required:

Microcontroller 89c2051

Crystal 12 mhz

Transistors npn- BC548

PNP- bc558

Optocouplers pc817

Resistors 1k – 10 nos

Servo motor- 12v 30 rpm

Rack and pinion assembly

Relays 12v 400E

8.2k, 470 E, 100 E

10 µf, 0.01µf,1000µf,470µf

Dc motors 12volt 30 rpm

Microcontroller programming kit

IC  bases

Gears assembly

Plastic Rods or plates

ply board

copper clad board

Applications

·        For industrial automation- we can control any machine using this system

·        For robotic for biomedical machines

·        For military application

·        For home automation

  Advantages:

•   Low cost

• Manpower reduction

• parts available in market

• Flexible