Single Point Machine Vision

01 October 2009

Machine vision technology provider Dalsa Corp has announced the availability of the BOA Vision System, its first highly integrated smart camera and one that comprises all of the elements of an industrial machine vision system in one package.

The tiny single-camera system is aimed at automated quality inspection and factory automation applications.

Multi-camera vision appliances are embedded solutions designed primarily to satisfy inspection needs, and in today’s market have become rather sophisticated.. They generally provide ease-of-use, performance, and flexibility required to meet the diverse requirements of industrial applications, while accommodating the needs and limited experience of end users.

Dalsa IPD (the IPD stands for Industrial Products of Dalsa) has been supplying machine vision for 25 years, and claims to be the only company to own all of the technology ingredients—including cameras, frame grabbers, software, vision appliances, and even the semiconductor fabrication of the CCD vision sensor chips.

While the company has built its reputation on multi-camera solutions, the new BOA product follows the latest trends in electronic control devices: packing everything into a single, simple box.

Steve Geraghty, director of Dalsa’s Industrial Products group, is not unaware that several competitors have supplied diminutive machine vision packages for at least the past ten years. But he claims his company has done its homework and come up with a substantially better product. Everything this new camera has to offer, he says, is inside the little 44 mm metal cube: the CCD sensor, light control, all the processing (with three different processing chips, no less) I/O, Ethernet communications, and developer and operator application interfaces. All of this is packaged inside an IP67 box that is so small, a golf ball would barely squeeze inside.

The IP67-rated housing means that the camera can be directly deployed in harsh, wash-down environments. This is particularly useful to meet cleanliness standards in the food and pharmaceutical industries, and eliminates the need for a separate protective enclosure.

“There are manufacturers today who have a variety of options available that offer a range of machine vision capability at various price points,” says Mr. Geraghty, “And each of them, in my opinion, provide only a part of the solution. Some come close, but they are always lacking something, such as an industrial enclosure. Most still have to connect to a PC where the software is running, plus, it’s not super-easy to use, and not super-easy to integrate. This is why we entered the market with our new BOA system. What we’re trying to convey is that we’ve put it all together in one package. That’s where we come to the table.”

It can do everything a machine vision inspection system is required to do. It captures an image, processes it, analyses it, and communicates immediately with the automation system if the part needs to be rejected. No external controller, PC, or server is required. The BOA stands by itself. All the software is embedded inside the box.

The technology inside

Mr. Geraghty adds another interesting claim to the one of supreme integration. He says Dalsa is the first to implement multiple processing engines.

There are in fact three processing chips inside each BOA: a DSP, CPU, and an FPGA.

The DSP is for algorithm development and optimisation; the CPU for interfacing with operators to configure or monitor the inspection, and for communicating the results with the factory environment; and an FPGA is used to get the image into the camera and manipulate its quality.

A key point in all of this is that BOA embeds the application software in the camera, which means it doesn’t depend on any external computer for support. If the operator wants to interface with the internal workings, for example to configure the software for an inspection application, he only needs to connect via a web browser.

“This eliminates all problems of revision control,” says Mr. Geraghty.

The embedded software application is the same as IPD’s iNspect™, which it sells as a PC-based package for its multi-camera systems. Developed for both first time users and machine vision experts, it represents about half the company’s software revenues. The other half comes from a more advanced package called Sherlock, which will also be ported to run on the BOA.

iNspect software is for end product manufacturers from a broad range of industries who either use or want to use vision to improve quality inspection or increase productivity, but who don’t want to become deeply involved in programming languages.

There are, of course, other segments of the machine vision market Dalsa hope to address.

For example, there are machine builders looking for platforms that can be customised to meet their needs, and small equipment manufacturers who want a private-brand platform to accelerate their time-to-market. For both of these customer segments, Dalsa provides support for combining their proprietary algorithms with iNspect and running it on the BOA platform. Alternatively, customers may only want to purchase the hardware platform and BOA-specific software libraries to create their own exclusive package.

One other trick up Dalsa’s sleeve is a PC-based software emulator that works in exactly the same way as the embedded iNspect software. This is a tool primarily intended for installers: they can run the camera at a new installation, capture some images on a flash memory drive and transfer them to the PC, where they can develop the application with the emulator. Once finished, the application can be sent back to the camera. The emulator mirrors the software in the camera, so the engineer is “seeing” exactly the same results.

One curious technology footnote: Although Dalsa has extensive semiconductor fabrication facilities in Canada and The Netherlands and makes its own machine vision sensor chips, these are mostly large format products for the high end of the market: sensors with at least 1000 x 1000 pixels. To keep the price of the camera under US $2,000, BOA will initially be equipped with a 640 x 480 CCD sensor (monochrome and colour), and the company is bringing in the chip from an outside source. Higher resolution models, says Mr. Geraghty, are in development.

An MV afterthought

“A lot of times with automation applications, we find that customers don’t think about machine vision up front,” says Mr. Geraghty. “They end up wanting to shoe horn it in after the line is up and running, because they’ve discovered they have quality problems, or something like that.”

The small form factor of the camera allows it to be easily integrated to existing lines. It can be attached to the end of a robot arm, for example.

The back side of the camera is the business end as far as external connections are concerned. Of the three M12 connectors, for many typical applications, only one of them need be used: the 100 MB Ethernet connection. A second connector is for I/O; it gives access to BOA inputs and output. This can be used, for example, to trigger the camera, or send output pulses to control the direction of automation equipment, etc. At the top is a dedicated connector for power and strobe control of an external lamp. The remaining space on the back is filled with a set of LEDs for status indication.

Dalsa engineers have come up with a clever way to power their little box. In the M12 cordset to the Ethernet port there are eight conductors; four for Ethernet signals, and four unused. Two of the four unused wires can be accessed for power supply. The camera works on 12 to 30 volts dc.

This is not Power over Ethernet (PoE) Mr. Geraghty hastens to add, but simply a matter of taking advantage of the unused cable capacity. And, for many customers, it’s a big advantage because it means they have to run only one cable to the camera.

Why 100 MB Ethernet, and not Gigabit Ethernet? Or Firewire? Or USB? Or something else?

In its multi-camera vision appliances, Dalsa supports all the standard communications options, right up through the multi-gigabit CameraLink, but the company sees 100 MB Ethernet as the emerging factory automation standard throughout the world. And so it figures this is the bandwagon to jump on.

But why not GigE, gigabit Ethernet? Why not go for high speed? This is machine vision, after all.

“We’re not providing images real-time as we connect;” says Mr. Geraghty. “We’re just providing the results of the inspection and 100 MB is fine for that purpose.

“We can send pictures over the Ethernet wire and the performance is, actually, not too bad. We can send 10 to 15 images per second but this is usually done during the set up period. During normal production runs, this is not normally done.”

Rather than looking at thousands of photos, users can take another approach.

“The camera has pretty good memory on board that allows customers to store results and failures, and look at them at any time. They can dial into the camera at any point and monitor what is happening.”

OK, so where’s the light source?

Critics may be forgiven for noting, almost immediately, that unlike many other small machine vision appliances, BOA has no lighting system. There’s no bank of LEDs circling the lens or sticking out of the camera. That’s the way it is.

No, Dalsa didn’t forget the lighting, says Mr. Geraghty.

“We recognise many cameras on the market have an integrated light source. We elected not to do that for two reasons. First, we wanted to keep the size of the camera small. And, secondly, our research has shown that in most applications, you can’t used the integrated lamp and you have to purchase and use an external lamp. So, we’ve found that the integrated lamp, in many applications, is wasted.”

Going forward

Dalsa will initially offer a 640 x 480 pixel monochrome BOA camera for US $1,995, which includes the full complement of tools. A colour version will be ready later this year.

“We can be very cost effective with multi-camera vision appliances,” says Mr. Geraghty, “and now we’ll be able to do the same with single-point applications.”

He says IPD’s traditional multi-camera markets are in automotive, electronics, medical, and packaging, with a new and growing interest in pharmaceuticals, where the interest is primarily in security, data logging, and compliance with FDA regulations.

“The BOA Vision System sets a new benchmark for single point inspection cameras in the industry,” says Mr. Geraghty. “It offers advanced vision capabilities that are easy to integrate at an affordable price, while consuming very little space and power.”

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