Vision Guided Intelligent Robot System Replaces CNC Machine Operator

Vision Guided Intelligent Robot System Replaces CNC Machine Operator

Introduction

The robot application should be developed in Ontario in the future. The “Vision Intelligent Robot System Replaces CNC Machine Operator” will be easily realized at present technology level.

Since the first industrial robot was online in a General Motors automobile factory in New Jersey in 1962, it has been applied in many fields such as auto assembly line, parts picking and release and so on. For these traditional applications, the robot is “blind”. It only knows the “position” in the real application. So the work piece is moved by robot at the specific position through some device. The device takes workshop area and needs time to manufacture for different part. These kinds device is not freedom to all of the parts. If this kind of robotic system is applied to replace CNC machine operator, many cases of them have no advantage than CNC machine Operator directly operates. So the robot replaces CNC machine operator applications are not wide enough. Due to the robotic technology development, the vision guided intelligent software can overcome the obstacle.  

Review technology history, Ford invented assembly line contributed the auto industrial development; Bill Gates created Windows Computer Operation System greatly contributed computer application. At present robot technology has already had all of the conditions to replace CNC machine operator to manufacture parts.

The automotive parts manufacture as the mainly industry in Ontario meets expensive labor salary in Canada and developing country lower salary competition. Although new immigration can solve some problems temporarily, the best way is to develop robot technology to decrease manufacture cost and increase competitive.

Background

Human history first progress is usage tools in which the tools are driven by the human muscle. Second progress is industrial revolution in which most part mechanical power replaced human muscle to finish the job by the guide of human. Now the third progress is the intelligent system to guide the machine to finish the object in which the human only indicates the purpose is OK.

Due to the robot itself technology is quite mature, if there is enough software support, the robot can do every thing. The key problem is intelligent software. Vision Guided Intelligent Robot System (VGIRS) software is one of the technologies. It seems like the computer. When the software problem is overcome, the next technology revolution will be robot application. The robots are widely applied in human life everywhere.

The recent vision guided development as follow：

2006 Increased adoption of 2-D vision guidance

2007 More innovation in 2-D vision guidance, 3-D vision guidance for bin picking and assembly inspection.

2008 3-D vision guidance begins replacing 2-D vision guidance due to cost reduction and increased processing power

2009 commercialization of vision-serving of robots using machine vision

Instead of locking a part’s position in advance to suit a blind robot, the VGIRS lets the robot sees the position of a loose part and adjust itself accordingly to manipulate it. So it needs to develop a system to see the components position, calculate the component’s position, grasp it, inspect it, and move it to where it needs to go.

The Vision Guided Robot System

Vision Intelligent Robot System comprises three sections:

l Robotic system

l Vision system

l CNC Machine Tool

A VGIS comprises a camera and microprocessor or computer, with associated software. A camera can be anything from a standard compact camera system with integrated vision processor to more complex laser sensors and high resolution high speed cameras. It can be used for quality control to check dimensions, angles, color or surface structure-or for the recognition of an object and determines the position of randomly products onto a Box or a pallet. The vision system and control software gives the robot exact coordinates of the components, which are spread out randomly under the camera field of vision, enabling the robot arm(s) to move to a selected component and pick from the container. This functionality is usually referred to as vision intelligent guided robotics (VIGR). It is a fast growing technology and a way to reduce manpower and retain production, especially in countries with high manufacturing overheads and labor costs.

VIGR systems advantages

Traditional automation means serial production with large batch sizes and limited flexibility. Complete automation lines are usually built up around a single product or possibly a small family of similar products that can run in the same production line. If a component is changed or if a complete new product is introduced, this usually causes large changes in the automation process-in most cases new component fixtures are required with time consuming set up procedures. If components are delivered to the process by traditional hoppers and vibratory feeders, new bowl feeder tooling or additional bowl feeder tops are required. It may be that different product must be manufactured on the same process line, the cost for pallets, fixtures and bowl feeders can often be a large part of the investment. Other areas to be considered are space constraints, storage of change parts, spare components, and changeover time between products.

VIGR systems can run side-by-side with very little mechanical set up, in the most extreme cases a gripper change is the only requirement, and the need to position components to set pick-up position is eliminated. With its vision system and control software, it is possible for the VGR system to handle different types of components. Parts with various geometry, can be fed in any random orientation to the system and be picked and placed without any mechanical changes to the machine, resulting in quick changeover times. Other features and benefits of VGR system are:

• Switching between products and batch runs is software controlled and very fast, with no mechanical adjustments.
• Short lead times, and short payback periods
• High machinery efficiency, reliability, and flexibility
• Possibility to integrate a majority of secondary operations such as deburring, clean blowing, washing, measuring and so on.
• Reduces manual work

Development VGIRS

The VGIR comprises of a 5-axis robot driven by its own controller. In this work we use CCD (charge coupled device) camera for capturing the two-dimensional image of the scene where the objects to be picked up lie. Software is used for processing the image (geometric matching, Shape and color analysis) and to find out the center of gravity of the object and its orientation. Interfacing card is used for connecting the computer to the robot. Values are sent to the robot via I/O card, which makes the robot to position its gripper accordingly in order to pick up the object and move it to the required destination.

The control diagram as follow:

Methodology

l  Selection a suitable existent robot traditional picks up and releases parts in CNC manufacture case to be innovated as a VIGRS

l  Document needs including part photographs, drawings of the part, the clamper, and robot manual

l  When testing in environment of traditional robot pick up manufacture line, put the freedom parts in the robot work range, the robot can “see” parts and automatically pick up the parts and release them at required position.

l  The VIGRS does not need machine operator. It only requires very simple assistant device and technician to maintain the system. It is easy to be changed for manufacture different parts through changing vision software. It is a real flexible production system.

Schedule

1. The project is for doctoral degree Scholarships in NEC. OGS, NSERC, SSHRC or CIHR or independent research project. Professor Simon. X. Yang is advisor.
2. It starts on 2011, Jan, if the there is application company funding. In two years or one year the prototype system will be appeared to show and to prove practicable of the system principle and application in real manufacture environment. The project needs four years to finish the system from the theory, principle to production equipment.
3. The total founding is $60,000 in 4 years. The most part of funding are researcher live cost and project test facilities.

Author notes:

The original preliminary idea is a simple proposal without detail steps. It was proposed by Bao Zeng Jia in 2006. He had researched the robot picks up tomato intelligent system from 2007 to 2009 by the guide of Professor. Simon. X. Yang in University of Guelph. The research is very close project of robot replaces CNC operator. The research of “Robot Picks up Tomato” and commercialized Clamping Garden Scissors contributes preliminary research of VIGRS. Therefore, the formal proposal was worked out with detail steps and process. All of these works are supervised by Professor Simon. X. Yang in University of Guelph.

Bao Zeng Jia

University of Guelph

Tel：519 265 5688

Email: [email protected]