Development of Web-Based E-Quality Control System

Principal Investigators: Drs. Richard Chiou and Yongjin Kwon Research Assistants: Prathaban Mookiah and Satish Anupindi

Applied Engineering Technology Goodwin College of Professional Studies, Drexel University, Philadelphia, PA

A web-based quality control system via E-machine vision on inspecting part dimensions and tolerance and connecting with robotic operations in manufacturing. The remote accessibility and the ability to control the equipment over the Internet present unprecedented benefits to the current manufacturing environment. Designers located remotely from the production facility can carry out the quality inspection and diagnosis as their design processes evolve. The remote quality monitoring system takes Java as a core and uses it to encode diagnostic data. The use of Java allows for seamless interconnection and data transfer between the different components of the web based quality system and the robots.  The Web based control chart can be automatically used to send diagnostic data and commands to on-line rejection of defective parts through Internet based robots.

Abstract

The project aims to develop an Internet based quality control system for manufacturing through a combination of Internet enabled industrial devices. The final outcome is to enable the quality control personal to receive quality information on the ongoing manufacturing process at a remote location over the Internet.

Objective:

SYSTEM ARCHITECTURE

SYSTEM SETUP

SYSTEM SOFTWARE ARCHITECTURE

SYSTEM DESCRIPTIONAll the subsystems are connected to the Goodwin College’s local area network at Drexel University.

Cognex DVT 540 Sensor•Used for making inspections and measurements•Equipped with Ethernet port and TCP/IP stack for information exchange•Initially trained to learn the profile and make measurements on the object being tested through the FrameWork software•Once an object is detected by the ObjectFinder soft-sensor, measurements are made automatically through the measurement soft-sensors•Inspection results reported back to application server through a TCP/IP connection

Yamaha YK 250X SCARA Robot•Particularly suitable for pick and place or assembly operations with a high degree of accuracy and speed •Variable speed Dorner 6100 conveyor system is connected with the robot’s I/O device ports in order to synchronize the conveyor with the motion of the robot•The robot’s RCX 40 controller is equipped with an Ethernet card and runs a Telnet daemon for remote textual command based operation of the robot

Mapping Between Robot – Camera Co-ordinates•Object position has to be mapped from camera coordinates to robot coordinates to guide the robot to the correct pickup position.

0RT.IR

0

0

)(

)(

and , 0

0 ,

b

a

y

x

S

S

b

ay

x

0RITR

Mapping given by:

where the robot coordinate vector R, scaling matrix T, image coordinate vector I and the reference robot coordinate vector R0 are given by:

Application Server•The application server is a communications program written in Java•Receives measurement data from the camera through a TCP/IP connection•Makes quality decision based on this data•Instructs the robot through a Telnet connection over TCP/IP to perform the appropriate pickup and place task based on the decision•Exchanges all this information with the user interface through a TCP/IP connection

User Interface•User interface implemented through a Java Applet and can be viewed through a web browser•Applet served by the Apache web server•Applet receives information about the ongoing manufacturing process from the application server and displays it to the user

Student Learning in E-quality Control System

Web-based E-quality Control System

0 5 10 15 20 2536.5

37

37.5

38

38.5

39

Sample Number

Mea

sure

d D

ista

nce

(mm

)

Measurements

CLUCL

LCL

Statistical Process Control Chart for CCD