Complex breakthrough makes automation simpler.
Listing of controllable spray painting or coating variables
Whether wet or powder, variables in spray painting that influence painting results, such as color and thickness, include many things. A list of the controllable or measurable variables in an ARTomation system is given below:
Linking: Key to total spray painting automation.
The technology currently controls coating variables dynamically and links them with measurable results. The current software method requires that humans record the results. This reliance on people typing in the information is a drawback, because it doesn't always get done. The future configuration of a patented ARTomation system, however, tracks coating variables dynamically, and then links them with measurable results, which will also be measured dynamically. This will close the loop, and provide a completely automated system.
Completely computer controlled with no human interaction, the system could update any information into its databanks, learning as variation in conditions occur, changing settings automatically to adjust-so when any variable changes the desired results, the results are brought back to specifications, and the application results.
There is a complete disconnect in typical robotic software because the motion and spray-gun settings are fixed. Typical robotic software doesn't make a connection between the variables in the process and the results of the application. If a part is presented to the robotic system slightly out of kilter, for example, the duplicate motion of waving the gun in front of that part, as it had done to the previous part, will miss it-and there won't be an "intuitive response" to alleviate the out-of-kilter problem. So the part will pass by without getting coated properly. This goes for every variable in an automation coatings system.
If one of the variables, such as flow rate, is slightly off from what was expected, hard automation typically does not adjust for it. While it is true that when it comes to controlling material flow, adjusting for viscosity changes in the coating material is achieved through "closed-loop flow control," there still is no connection to the results. Further, maintaining a consistent flow rate while not measuring the results does not guarantee that viscosity changes affect the outcome, and to what degree.
Because there is a connection between the process and the results, the architecture of an ARTomation system enables adjustment to offset the effect of a changed variable. If the temperature in the room goes up, for instance, and the flow rate out of the nozzle changes so it flows faster, an ARTomation system would sense this, adjust the settings to the flow rate, check to see what the results are before and after the adjustment in the settings and determine the effect of this variation.
As results are entered into the database, the system would automatically adjust the flow rate to bring back the results to what was specified.
The technology enables one to see what effect a change to any of the variables has on the results. It is the architecture of the ARTomation technology, and the robustness of the software (with some help from hardware) that makes this dynamic response and tracking possible.
While having flexible and expandable software residing in fast and beefy computers has been very critical to achieving a comprehensible integration of many disciplines, machine control advancements have also played a key role in the technology's usefulness and low cost.
An ARTomation system has the capability of linking all the influencing variables into one collection of information that can be sorted and later reviewed-from which conclusions can be made for making automatic adjustments in the future. One of the most important variables is the speed at which a spray nozzle passes over the surface of the part being painted, and at what angle the nozzle is at relative to that surface.
There are two basic configurations of machines that address the majority of the applications market: Upright and Overhead style machines. Uprights aim the gun straight ahead, much like an articulated arm. Overhead conveyors on which parts are hung on a rack are the typical auxiliary equipment for this style machine. An overhead ARTomation machine usually hangs over the parts, which typically get painted while in a fixture or on a spindle. Roller-type conveyors or chain-on-edge conveyors are typically used in these types of applications. These machines typically have three- or five-axis motion, and can be built to size, and are typically designed around the largest part to be coated by the system.
Software applications
A general belief in painting is that there are just too many variables to control, and their relationship to each other is just too complicated for "smart" automation systems to understand. Because of the time needed to be dedicated to a robotic system, it is also widely held that automation is just too expensive. Even in today's highly technological society nearly 80 percent of the coated products are done so by hand.
But now with ARTomation technology by Cleveland-based Advanced Robotic Technologies, the relationship between a virtually infinite number of variables in a spray-coating operating can be catalogued into a database and their relationship to each other understood as the collection of raw data begins to make sense out of what once seemed to be a chaotic situation. Further, ARTomation has been shown to pay for itself within the first year of operation through the savings in paint consumption alone.
The basic principle, therefore, is that contrary to the generally held belief, the relationship between variables in paint finishing and coating application can be understood when tracked by a computer database; and control systems can be implemented using this acquired information so that the reliance on hand-eye coordination can become much less, if not eliminated.
ART has two software applications, which would reside on a desktop computer: WetCoatT for wet-coating applications, and DryCoatT for powder coating.
In order to program an ARTomation system, first a digital picture of the part or rack of parts is taken. Then the picture is opened in the ARTomation software application, and with a few clicks of the computer mouse the software knows how big the part is in the real world.
Next, the user tells the software where the robot's "frame-of-reference" is by simply selecting the one point on the part that has been predetermined when the robotic system was installed. Now the user is ready to draw the paint paths using the tool pallet to select a line and its path, as well as the projection of the spray pattern.
Once the paint path is drawn and positioned, "Properties" may be opened by double clicking the paint path or right clicking and opening Properties. In this window the user sets the gun settings, using the pull-down menu boxes to select settings for speed, angle, atomization air, fan air, KV flow rate, distance the part is from the conveyor's center line and the distance between the gun and the part. These last two measurements are derived from using a tape measure.
The user can copy and paste paint paths and all the positioning, as well as speed and process settings. Once the user completes drawing all the paint paths and has specified what the system needs to do, the user simply clicks on the "Generate Spray Path" icon and the software creates a robot program transferable to the robot controller. This is most commonly done using Ethernet.
At the controller on the factory floor, the user selects the program and selects "run" to watch it go. If a correction is necessary once the user has observed the program, the file can be opened at the controller and changes can be made in seconds.
Results are entered into the database, providing reliable information that can be used to create a new painting program for new parts. The software eventually builds a bank of information about the different coating materials used and their behavior under different environmental conditions using different spraying equipment.
Once measurements are entered into the system dynamically, information can be taken on the fly; when a variable needs to be changed by the operator because of some changed condition, that event is recorded so that when the condition occurs again, the computer has historical information. This can be a very powerful tool, especially when a key person leaves a firm. The information and skills they have gained in running the system won't leave with them. The next person using the system will only help to improve the knowledge base.
