Flexible Automation:

Introduction:

The environmental effects of the modern mass-produced automobile are ofter attributed exclusively to its exhaust emmision during operation. Indeed, several megatons of carbon, sulfur, and nitrogen oxide, as well as smoke and residual hydrocarbons are released annually by some 560 million vehicles registered worldwide.

Despite popular expectation that internal combustion engines will be replaced by electric power, automotive pollution will not be entirely elliminated. Besides combustion by-products, the modern automobile contains several on-board contaminating materials that may be classified as corrosive, flammable, toxic, carcinogenic, or detrimental to the atmoshperic ozone. To this inheritance, future electric vehicles will soon add their share of pollutant fluids in their large battery packs which may pollute the atmosphere with SO2 emmisions. Also, as future automobiles will be equipped with air conditioning systems as a standard confort feature. Gaseous contaminants are represented by the fluid that has been used in these systems which are CFCs.

Practically the entire quantity of these automotive pollutants are destined to be eventually released into the environment at various stages of the vehicle life, with all the concomitant health, safety, and esthetic and economic implications. During automobile operation, fluid contaminants frequently escape through emissions or leakage, especially under poor maintenance or mechanical malfunctioning. Therefore, with the current rate of environmental pollution, we are literally destroying this wonderful planet, and we will not have anything to pass to the next generation.

As modern automation technology constantly improves, a computer-controlled inspection station using the method based on an artificial intelligence system for providing maintenance, detection, and repair will elliminate or reducve the above listed problems.

The unique approach of automated pollution prevention systems will include:


• Retrieval and analysis of the pollutant time record from the automobile OASES (on-board automobile systems for environmental safety)
• Inspection of the problematic unit for leakage at various locations, using special detectors.
• Integration of this information to diagnose the cause of pollution and locate the defective part.
• Safe extraction of the contaminant from the vehicle for recycling or disposal.

The efficacy of this novel environmental technology will be demostrated in the laboratory through a compatible OASES prototype.

The productivity and quality advantages of flexible automation in production can also be realized in the purpose of flexible automated repair of expensive, complex, and unique products. In the present context suffices to notice that for most commercial products, automated production has decreased the cost of their replacement when they fail, to the point that hteir repair is considered a rather costly, unreliable and thus unjustifiable alternative. It is clear that the economic importance of repair was limited because repair procedures did not lend themselves to automation as successfully as production. This is because their requirements for advanced testing and judgement abilities for the multitude of possible product defects made the human technician hard to replace by machinery of reasonable sophistication in the past. However, recent advances in sensor technology and machine intelligence provide the means for automated repair. For the above listed products, it is evident that the automation is critical for economic feasablity of repair. The arguements for this innovation is similar to those for automated production. Moreover, flexible robotic systems are now replacing hard automation in industrial cases where a variety of models and diversified products must be fabricated. In automated repair, flexibility is even more important, because of the addtional multitude of defect types that must be diagnosed and repaired. Thus, felxible robotic repair systems will ensure the following additional advantages:
• A larger class of products and variety of defects can be handled with a shorter reaction time.
• Additional products and/or defects can be repaired by adding or modifying its existent software, without the need for extensive hardware modification.
• More cost efficient use, and resistance to obsolescence of the general purpose hardware.

Clearly, the flexible robotic repair system has much in common with the flexible manufacturing systems, which have been subjected to extensive research and are now widely accepted in production industry. however, one essential difference of repair from flexible manufacturing systems lies in the necessity to detect various defects through appropriate sensing equipments. A second additional need for repair is the identification of the type and characteristic of defect on the basis of sensory tests. The third additional need is in the robotic field which involves path planning for collision avoidance, and offline programming and arm manipulation.

In this research, a flexible robotic repair system is developed to test and identify defective structure of various planar circuit boards using information provided by the vision system, end effector, and testing instruments. The defect is further investigated using diagnostic logic, and a replace repair process will be performed as suggested by an expert repair information base. The restructuring process will also be performed using a heirarchical model.