Vision Systems for Automation

Vision systems are the eyes that help automation complete the manufacture of products in the most accurate way. Usually a vision system is made up of any one of various cameras or sensors that is connected to the controller of the manufacturing operations. Through the connection the vision system sends images or other feedback to the controller to continually let the "brain" know what is the current state of manufacturing operation at every moment. The controller can make a decision about a next step in the manufacturing process based on the images that it receives from one or more vision systems or sensors. Instructions that can come from the controller to the manufacturing devices as a result of images it receives can be anything from "continue on to the next step" to "totally shutdown manufacturing" and everything in between. Vision systems have become part of the safety process that keeps manufacturing running. It is important for devices to be stopped when parts are products are out-of-place or not available for other devices to process. In some cases if devices are not shut down when parts are not available, equipment could be damaged, bringing the entire manufacturing operation down for costly repairs.

Vision systems have moved from being devices that are nice to have in manufacturing to necessities for making manufacturing as efficient as possible. When these systems were first introduced for use in manufacturing the technology was adequate, but did not give vision devices all the abilities that they have today. The main purpose of vision systems are to examine the state of parts and products during the manufacturing process. This inspection is done to determine positions of pieces, accuracy of production, and availability of products. The accuracy of production relates to the inspection of products in the various phases of manufacturing. If a product has been partially assembled in such a way that the completion of its assembly would cause the manufacturing process to be put into jeopardy, the controller will likely shutdown the process. In some cases the controller will have the option to send an improperly assembled product off the production line so that a full shutdown is not necessary. Technology has brought forth the 3-D and high definition cameras that the work of any vision system very effective.

Another use of vision and sensor systems is in the determination the position of parts and partially assembled as they move down the production line. In some production scenarios parts move down a belt toward an assembly operation. The part are in random positions as they move along. In order for the next step in the manufacturing to be completed, a robotic device is required to pick up each part so that it can be joined with another part to continue the process. The vision system make the robotic aware of the position of each incoming part so that it can be picked up efficiently. Without the vision system in this case high-speed production would not be possible. It is also possible that the vision system in this case would act as a safety mechanism. It would alarm the controller if there were no parts available on the production line so that precautions could be taken.

Usually the setup of a vision system is not very complicated and the system can be used in production with very little training of personnel. The benefit of a well-coordinated vision system brings a great deal of utility to your production environment without very much expense and effort. In some cases such a system includes a controller for the vision, an operating system, an intelligent camera, and the applications software to run the camera, all bundled together as a single unit. Usually the operating system is Windows, which is well-known and easy to use. Often these types of systems are used in packaging functions like inspecting the inside of containers or reviewing the amount of contents in containers in a filling operation. Sometimes they are also used in label placement inspection or in the inspection of tamper-resistance seals on containers. Vision is effective in reviewing package and container integrity or inspecting for contaminants inside product containers. Package counting and the confirmation of product inserts are other applications.

Considerations for applying a vision application to your manufacturing should include such thoughts as the speed that your production line will require for reduced impact on overall line speed. You should review all the areas that will need vision in your manufacturing to make sure that adequate vision coverage is in place to get optimum return. Review the environmental requirements of a possible vision option o make sure your production will allow what the system needs to do the job as you expect it to be done. This would include temperature and lighting considerations.

Pick and Place Automation

The ultimate in pick and place automation is being able to control an entire product handling system from a single controller. In a lot of cases in the past pick and place automation has been accomplished by having a series of pick and place robotics working in tandem with each other, but each was controlled by its own controller. There was a need for very fine synchronization between the controllers to accomplish the tasks required in manufacturing. Anyone can see that the coordination of application programs that instruct each device in the tasks that they need perform needs to be fine tuned since the actions of one device will impact the actions of another device. There is a domino effect established in work that is done on the production line. Add to the scenario the requirement of super high speed and the synchronization becomes even more critical.

Fortunately technology has been able to come up with an effective replacement for the pick and place automation scenario as described above. The state-of-the-art solution lies in the fact that there are controllers available now that combine motion, logic, and robotic control into a single controller. These highly controlled and high speed devices allow for efficient multitasking. Synchronization with belt speed allows the multiple devices that are instructed by a single controller to do insertion of products into primary and then secondary wrapping. It is possible to operate three robotic devices from the controller, but a fourth can be added that does not cause degradation in performance.

Logistics for this type system are made much easier because of the characteristics of the devices. It is much easier to install this controller and it subordinate devices. There is no need for interfaces to be installed so that each device can communicate with other devices. This says nothing of the tuning that must be done to synchronize several automation machines hooked to separate controllers. All the coordination happens in the single controller. The synchronization has to make sure that collision prevention is in place and setup correctly. With the single controller, this is not needed. The space that the single controller occupies is much less than its counterpart of multiple controllers. There is a dramatic reduction in the space for the single controller and the amount of space and time required for installation of cabling.

These state-of-the-art controllers also offer significant expandability in kinematics, being able to control 16 kinematics simultaneously. There is also the ability to add more axes and synchronized belts for further utility. Reducing the number of interfaces for such a system while cutting the cost of added components for automation are great attractions for such a set of devices. As technology continues to contribute to automation it is likely that this package of devices will become smaller in size and greater in flexibility and utility.

The application of the pick and place automation is very well-suited to the packaging of food and other products. Manufacturers of multiple lines of small food products can readily apply this set of devices in their manufacturing lines with almost immediate payback. Such a scenario lends itself very well to being used for multiple production jobs where pick and place and multiple product wrappings may be required for each product. The changeover from one production job to another is very efficient and will cut down significantly on the expense of setup for each production job. To make the entire production environment as efficient as possible it would be necessary to have a complete library of application programs completed and tested, ready to be loaded into the controller. This would further streamline the changeover process between jobs that could be done on the line where these devices are installed.

The combination of pick and place automation and vision or sensor systems makes for a very efficient automation solution for manufacturing. The sensory component gives feedback to the robotic component as to the location of parts that should be the attention of the pick and place operation. Add the speed component into this combination of devices and you have a very speedy automation operation. Feedback from the sensory device to the controller is so fast that it easily stays ahead of the movement of the pick and place device. The next instruction is ready for the robotic as soon as it has told the controller that it is ready to receive it. Having three pick and place robotics attached to the controller does not cause any degradation for the overall process. A high degree of accuracy is also achieved by all the material movement devices as they complete the manufacturing instructions.