Application story for industrial robot for supply chain (automotive) feature

Citation

(1999), "Application story for industrial robot for supply chain (automotive) feature", Assembly Automation, Vol. 19 No. 4. https://doi.org/10.1108/aa.1999.03319dab.020

Application story for industrial robot for supply chain (automotive) feature

Keywords Robots, Supply chain

Control systems and robots supplied by Letchworth-based System Devices are helping a Welsh based car speaker manufacturer to improve efficiency and win new business in a highly-competitive market.

Located at Bridgend, Harman Motive has a long tradition of supplying speakers. Founded in London in 1946, it originally supplied loud speakers for the UK's fledgling TV and radio industries. In the 1960s the company refocused its business on the automotive market, where demand for in-car entertainment was growing rapidly. By the late 1970s it had outgrown the London location and set up a small satellite operation in Bridgend, to where the whole company relocated in the mid-1980s.

Now one of the Harman International Industries businesses, Harman Motive is part of the OEM Group which supplies audio system products to leading car manufacturers in North America, Europe and Japan. Major customers include Land Rover, Jaguar, BMW and Saab. Today it employs over 400 people at Bridgend and expects to increase sales volumes significantly over the next five years.

Much of this growth will be driven by Opto 22 controls and Epson robots supplied by System Devices (see Plate 6).

Plate 6 Much of Harman Motive's growth will be driven by Opto 22 controls and Epson robots supplied by System Devices

Of six assembly lines currently in use at the plant, three use Opto technology. The first of these, speaker pre-assembly Line 2A, was commissioned in 1995. A second pre-assembly line, Line 3A, was installed in early 1997. Line 3B, a finishing/testing line, began work last summer. A fourth line, which will use Opto technology, is also on the drawing board.

Lines 2A and 3A use the same type and number of Opto systems. Each of the 11 work stations on the lines has a remote telemetry unit (RTU), which in turn is linked to:

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  one actuator controller via an RS232 link;

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  one station operator handset via an RS232 link;

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  one tag reader/writer via an RS232 link;

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  one node link via an RS422 network to the real-time process monitoring (RPM) RTU which is responsible for data acquisition and correction of specific process parameters. An HP9000 communicates the RPM RTUs to collect data and display real-time SPC graphs;

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  one ARCnet link to the hub.

The main controller for each workstation is Opto's Mistic, which itself is linked to:

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  one tag reader/writer via an RS232;

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  one RS485 network to all distributed I/O bricks responsible for controlling conveyor motions;

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  one ARCnet link to the hub.

In lines 2A and 3A, Opto's Cyrano runs in all controllers, while an older man machine interface (MMI) runs in the PC. the MMI PC is linked to the hub, allowing information to be downloaded from all controllers in a line.

The situation is slightly different in Line 3B, the finishing/testing line. Although every station has an RTU, main control is via an ISA board in the PC rather than Mistic. Each RTU is linked to:

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  one actuator Epson robot controller via an RS232 link. Three types of Epson robots used are used on the line: one SRC-320, four SCARA and one Cartesian;

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  one station operator handset via an RS232 link;

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  one measuring device (scales) via an RS232 link.

In Line 3B, the tag reader is attached to the Epson robot itself via an RS232 link. The main controller in the PC is linked to:

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  one tag reader/writer via an RS232 link;

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  one RS485 network to all distributed I/O bricks that control conveyor motions;

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  the MMI PC motherboard via back-panel PC ISA bus.

The MMI PC is housed in the same PC as the ISA board. Via one ARCnet link to the hub, it can download information about all controllers and show their status.

Commenting on Line 3B, Harman Motive Project Systems Engineer Alain Houdin said: "The benefit of the new system is that it is the first step in isolating conveyor control within individual stations to give fully asynchronous performance. This is thanks to the ability of Epson robots to carry more communications and more I/Os".

Training has been an important part of the company's migration to Opto and Epson devices, so Harman Motive has set up a training area which includes an Epson SCARA robot and a two-metre section of conveyor which can simulate all functions found in the main plant. "We've run two courses on Opto and one on Epson", said Houdin.

Opto is also at the heart of future plans at Harman Motive and Houdin hopes to migrate to factory floor after 2000. "In the meantime, we are upgrading the Cyrano and MMI on Lines 2A and 3A to year 2000 compliant versions", he noted.

Funding has been approved for a fourth line, known as 2B. It will also rely on Opto technology. A duplicate of Line 3B, it will be the finishing section of Line 2A.

"Opto has many benefits, but for us the most important aspects have been its ability to communicate with many different controllers and its ease of programming compared to the PLC alternative", concluded Houdin.