A robot is a reprogrammable multifunctional manipulator designed to move specialized devices, through variable programmed motions for the performance of a variety of tasks.
Actually, robot manipulators are interesting machines in terms of flexibility, programmability, and precision.
Robot manipulators present the best rate between “production cost” and “production volume” for small/medium production volumes and are unique flexible machines that can be adapted to perform significantly different tasks.
Material Required:
Welding machine power supply
Robotic arm
Torch
Welding fixtures
Sensors for Welding Robots:
Sensors for Technological Parameters -
Arc Voltage
Welding Current
Hall Effect Sensor
Current Shunt
Sensors for Geometrical Parameters
Optical Sensors
Through-arc Sensing
Safety equipment
Electronic controls and human-machine interfaces (HMI)
The application enables the user to work on the CAD file, defining the welding and approach paths between two consecutive welds, and organize them in the desired welding sequence.
When definition is complete, a small program converts it to robot commands that can be immediately tested for detailed tuning.
A set of tools is then available to speed up necessary corrections, which can be made online with the robot moving.
After a few simulations (robot performing all motions without welding) the program is ready for production.
If the user follows some basic rules, and produces a DXF file with all the information needed, then the application developed is capable of extracting that information from the CAD file.
3. Overview
● A robot is a reprogrammable multifunctional manipulator designed to move
specialized devices, through variable programmed motions for the performance of a
variety of tasks.
● Actually robot manipulators are interesting machines in terms of flexibility,
programmability and precision.
● Robots manipulators present the best rate between “production cost” and
“production volume” for small/medium production volumes and are unique flexible
machines that can be adapted to perform very different tasks.
4. Material Required
● Welding machine power supply
● Robotic arm
● Torch
● Welding fixtures
● Sensors for Welding Robots:
○ Sensors for Technological Parameters -
■ Arc Voltage
■ Welding Current
■ Hall Effect Sensor
■ Current Shunt
○ Sensors for Geometrical Parameters
■ Optical Sensors
■ Through-arc Sensing
● Safety equipment
● Electronic controls and human-machine interfaces (HMI)
5. CAD Modelling
● The application enables the user to work on the CAD file, defining
the welding and approach paths between two consecutive welds,
and organize them in the desired welding sequence.
● When definition is complete, a small program converts it to robot
commands that can be immediately tested for detailed tuning.
● A set of tools is then available to speed up necessary corrections,
which can be made online with the robot moving.
● After a few simulations (robot performing all motions without
welding) the program is ready for production.
● If the user follows some basic rules, and produces a DXF file with
all the information needed, then the application developed is
capable of extracting that information from the CAD file.
Figure 1
6. Process Planning
● The user starts by having a 3D drawing of the piece to weld and of the table used to hold
the piece. The 3D models should be very precise.
● Then the user should draw (Figure 1) all the trajectories required to fully weld the piece
as desired, i.e. using one layer for each trajectory.
● The welding parameters (velocity, voltage, torch distance to the surface) are introduced
in the selected layer.
● The weld layers should then be renamed for easy identification.
● The DXF file generated by the CAD application (AUTOCAD in our case) includes all the
information added to specify the welding process.
● Since the DXF file is an ASCII file, it is very
easy to extract the above-mentioned
information, using a simple application
given below.
● Here the definition shown in Figure 1 was
used.
Figure 2
7. Process Planning
● The generated dat file is used as input for the application
shown in Figure 3.
● This application shows the available definition with the help
of several push-down buttons.
● It enables the user to change the welding parameters, correct
points and orientations, simulate the whole process using the
real robot and the real piece to weld.
● The simulation is very realistic, making the final program
ready for production.
● The laboratory set-up (Figure 4) is composed of an industrial
robot, equipped with a welding
power source controlled from
the robot using our own
software.
Figure 3
Figure 4
8. ● Most important application of computer in welding is for the setting of welding
parameters.
● Computer is used to control the welding process with regard to both static and
dynamic characteristics.
● To improve the level of automation a CAD-based off-line programming system for arc
welding robots is also a part of computing.
● Computerised numerical control is necessary when the process requires two or more
dimensional axes to be controlled simultaneously.
● A computerised welding process controller is designed to handle the various
phenomena occurring during the welding process, viz., the start-up sequence,
continuous welding-including parameter setting, and the termination sequence.
Role of Computers
9. Manufacturing Process
Material Requirements
Gathering
information of the
material required
CAD Modelling
Understanding the
CAD Modelling for
ARC Welding Robot
Process Planning
Creating the CAD
Model with the help
of the available
applications and
making the final
program ready for
production
Designing of Model
Manufacturing the
ARC Welding Robot
according to the
design proposed for
production.
Stage 3 Stage 4
Stage 2
Stage 1 Stage 5
Model Testing
The model produced
with the help of the
design is tested
whether it is working
properly or not.
10. Swing and Move in Welding Arm
● Robotic arm can move side to side very
easily as you look from a distance.
● For a robotic arm to be able to function
with speed efficiently.
● It requires a one of the most important
component motors..
Assignment 2
11. Two types of motors can
be used in the welding
arm robot
Fig: Stepper Motor Fig: Servo Motor
12. ● An assembly of electronics that consists of SC and DC electric motors, a
potentiometer, and a controller board.
● A case made of plastic housing that accommodates the motor and other
important components.
● Several drive gears help regulate the speed of the motors. This is
important as it affects how fast the arm can move.
● An output spline is attached to an output shaft as the final interaction
point between the object of the motion being created and the servo motor
itself.
13. How a Servo Motor Works
● There are many types of servo motors that are used for many works.
○ It all begins when a signal is sent to the servo from the motion controller.
○ The servo then begins rotating a certain amount depending on the pulse width
modulation of the signal that has been sent over.
○ The position of the output spline is monitored by the potentiometer.
○ When the desired position is reached, the power supply to the motor is
immediately cut, and the servo is forced to hold that position until another
signal.
○ Servo motor is able to operate as fast as it needs.
14. Advantages of Using Servo Motor for Robotic
Arm
● High Torque Density
● Flexible Movement
● High-Precision
● Programmability
● Reliability and Durability
● Safety
● Quiet
● Small
