05-01-2013, 03:05 PM
MICROCONTROLLER BASED AUTOMATIC DRILLING MACHINE
[attachment=46567]
ABSTRACT
In order to form a new entity in the field of automation, an effort is taken to design and fabricate an automatic drilling machine with the help of microcontroller. Keeping in view the importance of reducing the lead time, total cost and manual work this project is accomplished.
In this project, a cycle of drilling process is automated with the help of a micro controller. Work pieces are queued on the conveyor and sensed by the sensor to stop the movement of the work piece at the required spot for the drilling process to be carried out. Here three stepper motors govern the movement of the conveyor, the drilling machine and the fixture. Thus these three stepper motors are controlled for the required sequence by the microcontroller.
The microcontroller is interfaced with PC for the purpose of giving input parameters such as depth, conveyor belt speed and total no of jobs to be drilled.
INTRODUCTION
Automation is a technology by which a process or procedure is accomplished without human assistance. It is implemented using a program of instructions combined with control system that executes the instructions. To automate a process, power is required, both to drive the process itself and to operate the program and the control systems. Although automation can be applied in a wide variety of areas, it is most closely associated with the manufacturing industries. It is ironing that nearly all the model of applications of automations are controlled by computer technologies.
The history of automation can be traced to the development of basic mechanical devices such as wheel, lever, winch, cam, screw, and gears in ancient times. These basic devices where refined and used to construct the mechanisms in wind mills, steam engines, etc., These machines generated the power to operate the other machinery of various kinds such as floor mills, weaving machines, machine tools, and rail road locomotives. Power and the capacity to generate it and transmit to operate a process is one of the three basic elements of an automated system.
One of the improvements was the flying ball governor which provided feed back to control the throttle of the engine. This is the second basic element of the automatic system. Third basic element of an automatic system is for the actions of the system or machine to be directed by a program of instructions. By the early 1800s, the three basic elements of automated system-power source, controls, and programmable machines-had been developed, although these elements were primitive by today’s standards. It took many years of refinements and many new inventions and developments, both in these basic elements as well as in enabling infrastructure of the manufacturing industries, before fully automated were to become a comman reality.
Important examples of these inventions and developments include interchangeable parts, electrification, the moving assembly lines, mechanized transfer lines for mass production, whose programs were fixed by the hardware configurations. Developments in computer technology where made possible by the advances in electronics including transistor, hard disks for computer memory, integrated circuits, microprocessors, microcontrollers,etc., Software developments related to automation have been equally important, including the FORTRAN
vi
computer programming language, the APT programming language for numerical control(NC )machine tools, the UNIX operating systems, the VAL language for robot programming, Microsoft windows, the JAVA programming language, C programming and embedded C programming for microcontrollers. Advances and enhancements in these languages continue.
BASIC ELEMENTS OF AN AUTOMATED SYSTEM
An automated system consists of three basic elements: (1) power to accomplish the process and operate the system, (2) the program of instructions to direct the process and (3) a control system to actuate the instructions. All systems that qualify as being automated include these three basic elements in one form or other.
POWER TO ACCOMPLISH THE PROCESS
The principle source of power in automated systems is electricity. Additional power is required for automating the following functions such as controller unit, power to actuate the control signals, data acquisition and information processing. The process are accomplished on discreet parts. These parts must be moved into proper position and orientation for the process to be performed, and power is required for this transport and placement functions.
Controller units make the control calculations and execute the instructions by transmitting the proper commands to the actuating device. The commands send by the unit are carried out by means of electromechanical devices, such as switches and motors called actuators. The transmitted signals are by means of low voltage signals. Hence information’s are processed on the basis of inputs given to control the algorithms.
PROGRAM OF INSTRUCTIONS
The actions performed by an automated process are defined by a program of instructions. The processing steps performed during a work cycle are specified in a work cycle program. The work cycle programs may be part programs in numeric control or ladder programming in plc s or C programming for microprocessors and controllers. Work cycle consists of essentially one step which is to maintain the single
vii
process parameter at a defined level. An extension of the simple case is when the single stop process is defined by more than one process parameter.
CONTROL SYSTEMS
Control systems is an automated system can be either closed loop or open loop. The open loop is one which doesn’t have a feed back. A closed loop system also known as feed back control system is one in which output variable is compared with an input parameter, and any difference between the two is used to drive the output into agreement with the input. It consists of elements like input parameter, process, output variable, feed back sensor, controller and actuator. The open loop case whish doesn’t have a feed back, a Stepper motor is used instead of a servo system as used in a closed loop system. A stepper Motor is designed to rotate a precise fraction of a turn for each pulse received from the controller.
ACTUAL PROCESS:
As far as this project is concerned, a microcontroller is used as the main control unit. It controls three stepper motor which performs the required operation at the correct operation sequence. A stepper motor is designed to rotate a precise fraction of a turn for each pulse received from the controller. Since the motor shaft is connected to the lead screw, and the lead screw drives the work table, each pulse converts into a small constant linear movement of the table. Here three stepper motors are employed. One controls the rotation of the conveyor which carries the workpiece.the other drives the fixture and the other controls the vertical linear movement of the drilling machine. Hence all the three stepper motors are programmed in correct operation sequence; inputs are given to the microcontroller through PC.
[attachment=46567]
ABSTRACT
In order to form a new entity in the field of automation, an effort is taken to design and fabricate an automatic drilling machine with the help of microcontroller. Keeping in view the importance of reducing the lead time, total cost and manual work this project is accomplished.
In this project, a cycle of drilling process is automated with the help of a micro controller. Work pieces are queued on the conveyor and sensed by the sensor to stop the movement of the work piece at the required spot for the drilling process to be carried out. Here three stepper motors govern the movement of the conveyor, the drilling machine and the fixture. Thus these three stepper motors are controlled for the required sequence by the microcontroller.
The microcontroller is interfaced with PC for the purpose of giving input parameters such as depth, conveyor belt speed and total no of jobs to be drilled.
INTRODUCTION
Automation is a technology by which a process or procedure is accomplished without human assistance. It is implemented using a program of instructions combined with control system that executes the instructions. To automate a process, power is required, both to drive the process itself and to operate the program and the control systems. Although automation can be applied in a wide variety of areas, it is most closely associated with the manufacturing industries. It is ironing that nearly all the model of applications of automations are controlled by computer technologies.
The history of automation can be traced to the development of basic mechanical devices such as wheel, lever, winch, cam, screw, and gears in ancient times. These basic devices where refined and used to construct the mechanisms in wind mills, steam engines, etc., These machines generated the power to operate the other machinery of various kinds such as floor mills, weaving machines, machine tools, and rail road locomotives. Power and the capacity to generate it and transmit to operate a process is one of the three basic elements of an automated system.
One of the improvements was the flying ball governor which provided feed back to control the throttle of the engine. This is the second basic element of the automatic system. Third basic element of an automatic system is for the actions of the system or machine to be directed by a program of instructions. By the early 1800s, the three basic elements of automated system-power source, controls, and programmable machines-had been developed, although these elements were primitive by today’s standards. It took many years of refinements and many new inventions and developments, both in these basic elements as well as in enabling infrastructure of the manufacturing industries, before fully automated were to become a comman reality.
Important examples of these inventions and developments include interchangeable parts, electrification, the moving assembly lines, mechanized transfer lines for mass production, whose programs were fixed by the hardware configurations. Developments in computer technology where made possible by the advances in electronics including transistor, hard disks for computer memory, integrated circuits, microprocessors, microcontrollers,etc., Software developments related to automation have been equally important, including the FORTRAN
vi
computer programming language, the APT programming language for numerical control(NC )machine tools, the UNIX operating systems, the VAL language for robot programming, Microsoft windows, the JAVA programming language, C programming and embedded C programming for microcontrollers. Advances and enhancements in these languages continue.
BASIC ELEMENTS OF AN AUTOMATED SYSTEM
An automated system consists of three basic elements: (1) power to accomplish the process and operate the system, (2) the program of instructions to direct the process and (3) a control system to actuate the instructions. All systems that qualify as being automated include these three basic elements in one form or other.
POWER TO ACCOMPLISH THE PROCESS
The principle source of power in automated systems is electricity. Additional power is required for automating the following functions such as controller unit, power to actuate the control signals, data acquisition and information processing. The process are accomplished on discreet parts. These parts must be moved into proper position and orientation for the process to be performed, and power is required for this transport and placement functions.
Controller units make the control calculations and execute the instructions by transmitting the proper commands to the actuating device. The commands send by the unit are carried out by means of electromechanical devices, such as switches and motors called actuators. The transmitted signals are by means of low voltage signals. Hence information’s are processed on the basis of inputs given to control the algorithms.
PROGRAM OF INSTRUCTIONS
The actions performed by an automated process are defined by a program of instructions. The processing steps performed during a work cycle are specified in a work cycle program. The work cycle programs may be part programs in numeric control or ladder programming in plc s or C programming for microprocessors and controllers. Work cycle consists of essentially one step which is to maintain the single
vii
process parameter at a defined level. An extension of the simple case is when the single stop process is defined by more than one process parameter.
CONTROL SYSTEMS
Control systems is an automated system can be either closed loop or open loop. The open loop is one which doesn’t have a feed back. A closed loop system also known as feed back control system is one in which output variable is compared with an input parameter, and any difference between the two is used to drive the output into agreement with the input. It consists of elements like input parameter, process, output variable, feed back sensor, controller and actuator. The open loop case whish doesn’t have a feed back, a Stepper motor is used instead of a servo system as used in a closed loop system. A stepper Motor is designed to rotate a precise fraction of a turn for each pulse received from the controller.
ACTUAL PROCESS:
As far as this project is concerned, a microcontroller is used as the main control unit. It controls three stepper motor which performs the required operation at the correct operation sequence. A stepper motor is designed to rotate a precise fraction of a turn for each pulse received from the controller. Since the motor shaft is connected to the lead screw, and the lead screw drives the work table, each pulse converts into a small constant linear movement of the table. Here three stepper motors are employed. One controls the rotation of the conveyor which carries the workpiece.the other drives the fixture and the other controls the vertical linear movement of the drilling machine. Hence all the three stepper motors are programmed in correct operation sequence; inputs are given to the microcontroller through PC.