MODULAR OPTOELECTRONIC SYSTEMS USED IN TRANSPORT LOGISTICS FLOWS AUTOMATIC INDUSTRIAL PRODUCTION

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1 Modular Optoelectronic Systems Used in Transport Logistics Flows Automatic Industrial Production MODULAR OPTOELECTRONIC SYSTEMS USED IN TRANSPORT LOGISTICS FLOWS AUTOMATIC INDUSTRIAL PRODUCTION Constantinescu Alexandru; Atanasescu Anca, Sorea Sorin, Constantin AngheL National Institute of Research and Development in Mechatronics and Measurement Technique 6-8-Pantelimon Str., 2nd District, Bucharest, Romania Abstract: The article aims at presenting and analyzing optimal technical solutions for modular optoelectronic systems and control software, easy implementable in interoperable transport logistics on the automatic production flows. They will ensure security of the production process, analyzed modules allowing identification of a large number of parts and components, their control and their pursuit in the production flow, checking them in many phases of the manufacturing and assembly process, including packaging and storage of the final product. It will be presented hardware and software modules that enable the widespread computerization of procedures for tracking products throughout the production. The final target aims for their integration into decision-making flow by sending information to superior management structures of production, telemonitoring the manufacturing process and / or remote maintenance equipment. Keywords: Optoelectronic Systems, Control, Informatics. 1. Introduction In the context of new constraints emerging in industry (technology evolves rapidly, the changing market, the migration staff) which requires a more efficient and flexible way to organize the production factors, the ability to continually improve the quality becomes an objective and a means to ensure competitiveness and performance on the Community market. The spectacular evolution of the computer industry on both components (hardware and software), and the dynamic development of the optoelectronic systems, have created the premises for implementing new control or dimensional measurement techniques that are also suitable for applications in automated industrial production flows. Using these optoelectronic systems, including intelligent image sensors, becomes possible during the last years also in Romania due to price cut-off, but involves knowledge and research or user experience in complementary areas (optical, high-resolution images acquisition, processing techniques and image analysis, cutting-edge programming languages etc). The promotion of such optoelectronic systems is highly recommended to a large range of industrial applications: products identification and control, monitoring the parts traceability between workstations (processing, assembly or packaging). 2. Architecture of optoelectronic devices and associated components modules Optical inspection with optoelectronic elements is a method commonly used in interoperable transport logistics applications. Optical inspection is an important part of the process of achiving quality in manufacturing. It may be effected off-line when the piece is removed from the process and brought into the inspection station, or on-line when the piece is inspected without being removed from the manufacturing process or by the production line, so that it can be returned to the manufacturing process as quickly as possible. Optical control is a vast subject. There are multiple configurations and architectures commonly used in the industry. Choosing the best method is the decisive step. Optoelectronic systems easily can be classified according to the level of complexity and type application, as follows: - Optical sensors, including: - Sensors for detecting contrast. Detects markings differentiate of their background by color contrast. - Sensors for detecting color. Serve to the non-contact recognition of the opaque and transparent objects based on their color. - Sensors for reflected light. The transmitter emits a light beam that is reflected back by a triple reflector. -Sensors for distance measurement. Measure the time duration of the light beam covering the distance between the emitter and receiver. - Laser sensors, including: 200

2 - Laser beam curtains. Consisting of a transmitter that emits a fine laser beam, which is perceived by the receiver. Laser beam interruption is evaluated. - Diaphragm reflected light. The transmitter emits a laser beam that is reflected back to the receiver module by a reflector. Laser beam interruption is evaluated. - Taster reflected light. Use the direct detection of objects. The transmitter emits a fine laser beam that is reflected back from the object to be detected. - Infrared / red light sensors, which comprise: - Infrared sensors. Infrared sensors detect heat emission from objects (transmitter) and convert it into an electrical signal. - Optical curtains. The transmitter emits infrared or red light. Receiver converts a beam interruption - given by object - into a switching signal. - Reflected light Diaphragm. With the help of a mirror, the emitted light beam is sent to a receiver. An object causes an interruption of the light signal. - Reflected light Taster. Use the direct detection of objects. The transmitter emits light that is reflected from the object and is detected and recognized by the receiver. - Optical waveguide, comprising: - Optical Fiber Amplifier. The transmitter and receiver module are in the same capsule. Depending on the version, the transmitter module emits a infrared or red beam. - Optical fibres. They are extensions of optical elements in optical fibre amplifiers. Can be glass fiber and metal coat or acrylic fiber. - Optical barriers/curtains for personal protection. Barriers detects human presence in dangerous areas around the production lines or equipment. - Barcode reader, 1D and 2D reading sensor. Independent of the orientation and number codes, the high-performance algorithms automatically decode 1D / 2D coding. - Object detection sensors (vision sensor), comprising: - Object Recognition Sensor. Intelligent sensor with integrated lighting and evaluation system. - 3D Sensor. Can evaluate objects in three dimensions. Image object Matrix or distance values Matrix correspond to a 3D image. - 3D Camera. Detects scenes and objects in their spatial dimension. Besides the 3D image distance, the camera also features a gray image of the scene. Figure 1 shows the types of optoelectronic sensors, including related modules that provides management of the entire production process. Figure 1: types of optoelectronic sensors, including related modules that provides management of the entire production process. BO - Light curtains, SP - proximity sensor, SF - recognition form sensor, S - barcode reader, CCD - intelligent camera, PLC - programmable logic control for industrial process, 3G GPRS - 3G GPRS, GPRS G - GPRS gateway, SV - server, W - wireless connection A1, A2, A3, A4 are four hardware architectures for control, service and remote monitoring: - A1 architecture 1 is composed of PC, INCDMTM server, GPRS and 3G router, PLC; - A2 architecture 2 consists of PC, INCDMTM server, GPRS Gateway, PLC; - A3 architecture 3 is composed of PC architecture, two GPRS GATEWAY type systems, PLC; - A4 Architecture 4 consists of PC system, GPRS Gateway, 3G and GPRS router, PLC. A5 and A6 are local communication architectures for higher hierarchical level: Wired or wireless 3. The applications range The range of optoelectronic systems applications is wide and is suitable for both "primary inspection" and leading applications, such as guiding robots or manipulators. 201

3 Figure 2: a - VMideo guided robot for handling parts; b -Position Checking on a conveyor Using optoelectronic sensors and cameras can be located parts in 2D or 3D, can be shifted or repositioned objects using manipulators or robots, can be performed operations using robots in "critical" areas, can be handled and stacked objects, pieces can be taken and positioned in relation to other parts for assembly, can be managed the traceability of parts, sub-assemblies and finished products. The optoelectronic elements and systems can be integrated successfully at local level, noting that, due to the specific domestic production method is recommended their use in activities such as: - Identifing a large number of articles and components - Tracking and guiding parts on production flow lines - Controlling or measuring parts and tracking them on manufacturing and assembly process, including packaging and loading for the final product. - Guiding robots - Monitoring product traceability - Automatic products stock management. 4. Applications implemented within INCDMTM Based on the above components, in INCDMTM have been developed complex computer assisted applications, which provides remote monitoring and teleservice activities for control equipment. Figure 3- Equipment for controlling cylinder head In Figure 3 is presented an equipment for controlling cylinder head type parts, which measured three types of holes (7 holes, 3 each in two directions and the 7th in a third direction) and check the presence of a thread on a fourth direction. Image acquisition and processing subassembly used consists of a color digital camera with GigE interface - made by PixeLink manufacturer, which has an 2/3 " size image sensor and a 1280x1024 pixel resolution associated with an optical zoom of 0.25x -1x. This camera has a high resolution and a field object large enough to fit the holes of interest for morphodimensional analysis. It is connected to a performant computer system, PC type, which runs the dedicated software for image acquisition, processing and analysis. The equipment is controlled by a Siemens Simatic PLC type from the S7-300 serie, and the user interface is via a Siemens OP-77A standard operator panel. The PLC 202

4 functions are for controlling the signals from the actuator controller, communication with the main PC, providing other signals required to implement acquisition functions, triggers, communication, lighting control. The developed software package provides (see Figure 4): - Moving the piece to the desired position for viewing - Local selection (from OP) of the displacement position - Remote selection (PC) of the displacement position - View parts with highlights - Control and measurement of elements of interest. Figure 4 - Software Application software comprises three components: - PLC program for driving the displacement axis - OP operator interface program for local selection of the displacement position - PC software for remote selection of the displacement position and/or for visualization and measurement of the elements of interest. In Figure 5 is shown a modular system designed to assist human operator in an assembly post on a production line characterized by high cadence, a high diversity of parts subject to assembly, multiple sizes of the same part, high changes of the manufacturing bursts. Basically in the same assembly post a human operator has to carry out similar operations but involving different subsets for different product versions for a production subject. 203

5 After the inserting of the parts into the proper compartment it is activated a switch to validate / alarm the action. Incorrect entries is signalled by lighting an error indicator. The control and command module is implemented with a Siemens PLC based on a S7314 CPU. The PLC comprises a power supply, digital inputs module, digital outputs module, two serial communication processors, a PROFIBUS DP communication processor for connection to higher-level system. 5. Conclusions Figure 5 modular system For implementing the functions of this equipment there are used the following probes: - Two proximity transducers for detecting the presence at input and output, placed on the conveyor belt, for sensing the paddles with parts over the mounting area; - Effector O2D Contour Pixel Dualis smart sensor, located at the entrance of the conveyor, designed to assess the conformity mark (in this case has to check the presence of thread on a hole that is common to the entire range); - An optical infrared retroreflective sensor to detect the part presence in the mounting position; - Barcode reader pointed in a position to read the label of the parts carrying blade; - Three pairs of curtain type optical barriers with bright signalling indicators that signal to the operator the compartment from which he had to take the part to be properly mounted conform with the identified version to be present in the post. They also sense the presence of the hand of the operator in the appropriate / inappropriate compartment. - Three proximity sensors on the back of the container to signal the container refill activities; - A barcode reader to identify the kinds of parts reloaded into containers. After reading a code it is activated the indicator light (flashing) for the appropriate compartment. The most appropriate approach of an industrial applications in terms of choosing the optical system needs a thorough analysis of the benefits and limitations of each possible solutions in order to obtain an optimally performance / cost ratio. This is achieved by comparing at least two technical solutions for solving the industrial applications, especially when they involved considerable costs as the use of either an intelligent image sensor, or of a CCD or CMOS camera integrated into a PC computer assisted equipment. Another aspect to be highlighted is that the optoelectronic systems can be used in applications of remote control, remote monitoring and teleservice to monitor and control the entire production flow and to accurately identify any production non-conformities. 6. References [1]. Data books: IFM, COGNEX, SICK, BANNER, WENGLOR, FESTO, BASLER [2]. INGINERIA INTEGRATOARE GHEORGHE, GHEORGHE ION, CEFIN Publishing House, 2007 [3]. INGINERIA SISTEMELOR SI INFORMATIEI, Gheorghe I. Gheorghe, Ulm Nicolae Spineanu, Doru Dumitru Palade, Valentin Pau, CEFIN Publishing House, 2005 [4]. µsenzorica, MECATRONICA SI ROBOTICA, Gheorghe I. Gheorghe, Doru Dumitru Palade, Valentin Pau, Florin Ion Popa, CEFIN Publishing House,