DE102004055318A1 - Multi functional field device, e.g. for detecting and manipulating liquid level, has digital image detecting unit for analyzing optical ambient information - Google Patents

Abstract

Multi functional field device has a digital image detecting unit (KA) e.g. charge coupled device (CCD) miniature camera, that is movably arranged. The detecting unit analyses optical ambient information, such as application specific information and control information. An evaluation unit, e.g. microprocessor, analyzes the data provided by the detection unit and conveys the data over a field bus.

Description

In In automation technology field devices are often used which serve to detect and / or influence process variables. examples for such field devices are level gauges, mass flow meters, pressure and temperature measuring devices, pH and conductivity meters, etc., as sensors the corresponding process variables level, Flow, pressure, temperature or pH value or conductivity value to capture.

to Influence of process variables are actuators, the z. B. as Valves the flow of a liquid in a pipe section or as pumps the level in a container Taxes.

When field devices are also called recording devices, which record measurement data on site.

A Variety of such field devices is manufactured and sold by Endress + Hauser.

In usually are field devices in modern automation systems via fieldbus systems (HART, Profibus, Foundation Fieldbus, etc.), with parent Units (eg control systems or control units). These Among other things, units are used for process control, process visualization, Process monitoring.

Most of time Fieldbus systems are integrated into corporate networks. So that can from different areas of a company to process or field device data be accessed.

to worldwide communication the company networks also with public Networks, z. B. connected to the Internet.

For process visualization stand in the parent Unit that is usually in a waiting room, only the one pure measured values of the sensors and the state values of the actuators to disposal. However, measured values alone do not provide a comprehensive overview of the Current process situation in a plant.

Partially therefore also surveillance cameras used that over corresponding cable lines are connected to the control room. On separate monitoring screens can so individual process components are also visually displayed.

Frequently a permanent visual surveillance a process component is not absolutely necessary. Is needed the visual information usually only in critical situations or for occasional sporadic checks.

Conventional surveillance cameras have several disadvantages. They are very expensive and expensive need a high cabling effort.

task The invention is therefore a multifunctional field device of automation technology indicate that does not have the disadvantages mentioned above, the especially the transmission of optical information to a higher-level unit.

Is solved This object is achieved by the features specified in claim 1. basics The idea of the invention is in a field device of automation technology to provide a digital image capture unit for evaluation optical environment information is used.

In an advantageous development of the invention is called digital Image capture unit used a CCD miniature camera. Such miniature cameras are already widely used in cellular phones and are as Bulk product relatively inexpensive.

Around the optical environment information also on the field device itself to be able to evaluate is in the field device a corresponding evaluation provided.

These Evaluation unit also serves for the preparation of the image acquisition unit supplied data for sending via the fieldbus.

at the optical environment information may be application specific Information, such as B. the level a liquid in a container, the color of the liquid or foaming on the surface the liquid.

Next This application-specific information can be the optical environment information also be control information, z. Eg hand signal of an operator, be.

In Advantageously, the image capture unit is arranged to be movable.

The Data of the image acquisition unit are transmitted via a corresponding field bus, Profibus, Foundation Fieldbus or HART to a higher-level unit forwarded.

at the multifunctional field device may be, for example, a pressure, temperature, flow or level sensor act.

following The invention is explained in more detail with reference to an embodiment shown in the drawing.

It demonstrate:

1 Network of automation technology in a schematic representation;

2 Block diagram of a field device according to the invention.

In 1 is a network of automation technology shown in more detail. On a data bus D1 several computer units in smaller workstations WS1, WS2, connected. These computer units serve as higher-level units (control systems or control units), among other things for process visualization, process monitoring and engineering, as well as for operating and monitoring field devices. The data bus D1 operates z. Eg according to the Profibus DP standard or according to the HSE (High Speed Ethernet) standard of the Foundation Fieldbus.

About one Gateway G1, which is also referred to as a linking device or as a segment coupler, the data bus D1 is connected to a field bus segment SM1. The Fieldbus segment SM1 consists of several field devices F1, F2, F3, F4, which have a Fieldbus FB are interconnected. In the field devices F1, F2, F3, F4 may be sensors or actuators. The fieldbus FB operates according to one of the known fieldbus standards Profibus, Foundation Fieldbus or HART.

In 2 is a block diagram of a field device according to the invention z. B. F1 shown in more detail. A microprocessor μP is connected to the measurement processing via an analog-to-digital converter A / D and an amplifier V to a sensor MA, which detects a process variable (eg, pressure, flow or level). The microprocessor μP is connected to a plurality of memories. The memory VM serves as a temporary (volatile) working memory RAM. Another memory EPROM or flash memory FLASH serves as memory for the executed in the microprocessor uP control program. In a non-volatile writeable data storage NVM z. B. EEPROM memory, parameter values (eg calibration data etc.) are stored.

The in the microprocessor μP expiring control program defines the application-related functionalities of the field device (Measured value calculation, envelope evaluation, Linearization of measured values, diagnostic tasks).

Farther is the microprocessor μP with a display operation unit A / B (e.g., multi-LCD display Push buttons) connected.

to Communication with the fieldbus segment SM1 is the microprocessor μP via a communication controller COM connected to a fieldbus interface FBS. A power supply NT provides the necessary energy for the individual electronic components of the field device F1. It can be from the fieldbus FB are fed or from another source of energy. The supply lines for the Energy supply of the individual components in the field device are clearly arranged not shown.

Of the Microprocessor μP is over a parallel interface with three signal lines data bus line DB, address bus line AB and a signal line SL with a digital Image acquisition unit KA connected. It is also conceivable a serial Data port.

at The digital image acquisition unit KA is a CCD miniature camera with a camera eye A of about 3-5 mm diameter. The image acquisition unit can be rigid or movable on casing of the field device F1 be arranged. A movable arrangement of the digital image acquisition unit is over for example a ball joint possible. The viewing angle of the camera eye A is through the two boundary lines indicated.

following the operation of the invention is explained in more detail. The of the digital Image acquisition unit KA supplied data are evaluated in the microprocessor uP and possibly over the fieldbus interface FBS via the fieldbus FB and the data bus D1 forwarded to the parent unit WS1. In the control room the plant operator can get an up-to-date picture of a process component call. In this direct from the process component originating Picture can Naturally current measured values are displayed. Such a digital one Image acquisition unit KA offers considerable benefits for the plant operator Advantages.

If the eye A of the optical imaging unit KA directed in a container, so z. B. the current position of a stirring blade are detected. Such an impeller detection can be used in level gauges according to the radar principle to avoid interference caused by the movement of the impeller. About properties of a tank contents, such as color, consistency liquid or granular, the system operator can also recognize which medium is currently in the tank container and, if necessary, make appropriate medium-dependent settings on the field device or on a controller.

The Of course, digital image acquisition unit KA can also be used for plausibility checks be used. The formation of foam or dust in a container can optically detected and the loss of a radar level echo is for The investment driver then plausible.

Next This application-specific information can also control information with the digital image capture unit are bordered. It is conceivable the movement of an operator's hand or fingers for device operation a field device to use. Furthermore, the Image capture unit a visual personal identification, a Operator on the field device. The identification itself can be done in the field device or in the control room by the Plant operators take place.

Claims (9)

Multifunctional field device of automation technology, which is used for detecting and / or influencing a physical measurement variable and which can be connected to a fieldbus, characterized in that the field device F1 has a digital image acquisition unit KA, which serves for the evaluation of optical environment information. Multifunctional field device according to claim 1, characterized in that the digital image acquisition unit KA has a CCD camera is. Multifunctional field device according to one of the preceding Claims, characterized in that an evaluation unit is provided, which serves to evaluate the data of the image acquisition unit KA. Multifunctional field device according to claim 3, characterized in that the evaluation unit is also used for processing the Data of the image acquisition unit for sending via the fieldbus FB is used. Multifunctional field device according to one of the preceding Claims, characterized in that the optical environment information is application specific Information is. Multifunctional field device according to one of the preceding Claims, characterized in that the optical environment information is operation information are. Multifunctional field device according to one of the preceding Claims, characterized in that the image capture unit KA is movable is arranged. Multifunctional field device according to one of the preceding Claims, characterized in that the fieldbus to the Profibus, Foundation Fieldbus or HART standard works. Multifunctional field device according to one of the preceding Claims, characterized in that the physical parameter pressure, Temperature, flow or level is.