Going steady

Creaform’s Handyscan, the first hand-held self-positioning 3D laser scanner on the market, is already finding a niche in motor racing and the medical field. Niall Firth reports.

In early 2002 two young entrepreneurs set up Canadian engineering firm Creaformto begin development work on the world’s first hand-held 3D laser scan camera.

For a fledgling business to invest heavily in such a new technology was a gamble but it turned out to be an inspired decision. In the year since its launch the result of that early research, Handyscan 3D, has earned its developers awards, industry accolades and — most importantly — a significant foothold in the competitive reverse-engineering market.

Although the Handyscan was launched only early last year in Canada — and its first UK distributors only received the first products in September — the device is already being used by a wide range of big automotive companies including Hyundai, Toyota and Renault.

Creaform has sold more than 100 of the devices since its launch. The Handyscan’s big selling point is that it is the first entirely self-positioning 3D rendering device available on the market, according to its product manager Marco St-Pierre.

‘It is the first true hand-held scanner in the world, which means you don’t need any external tracking device,’ said St-Pierre. ‘If you compare it to other products that are in the same category they all need a control measurement machine ( CMM) or a measuring arm to hold the system and to let it know where it is in space. Handyscan doesn’t need this, which makes it very attractive.’

According to St-Pierre the existing, larger machines that translate physical objects into 3D virtual models are static, bulky and difficult to manipulate. He said that other efforts by engineering firms to develop a portable device have still always needed a tracking arm, something conspicuous by its absence in the Handyscan.

While its portability may be its initial main selling point, the interesting technology that makes this possible is that fact that the Handyscan is self-positioning. When an object is to be modelled, reflective targets must first be affixed to its surface. The Handyscan is then pointed towards the object and the self-positioning cross-hair laser is swept across its entire surface.

The system is then able to use the data created from this initial scan to track where it is in relation to the object and, cleverly, where it is in 3D space. It can create a highly accurate 3D image of the object which is directly imported into a CAD software application on the accompanying laptop.

By tracking the positional data from the reflective targets the Handyscan builds a reference model in real time and knows where it is in space in relation to the object by recognising the target’s patterns.

The system uses two extremely high-resolution cameras which Creaform claims are accurate to within 0.05mm and can create around 18,000 separate measurements per second.

With the two cameras positioned slightly inwards at an angle to the laser the device uses triangulation combined with sophisticated software to work out exactly how far away the object is. This means that the Handyscan does not need to be held steadily because the in-built self-positioning software can adapt and recalculate the distance in real time. According to St-Pierre, this is a breakthrough in 3D scanning.

‘We are generating a surface in real time by making triangles with each set of three marker points on the object’s surface,’ he said.

These data points are then processed — or meshed — automatically and are converted into an STL file on the accompanying laptop.

‘With other systems you take all these points and then use a post- treatment software to clean them up and to create the meshing for the STL file — this creates the 3D model,’ explained St-Pierre. ‘We skip the software part as we are generating this surface in real time. It is already meshed. This means you save time and money. There is no other system on the market comparable to the Handyscan in this regard.’

The hand-held device can be used to scan car parts both before and after testing to see where any component degradation has taken place

Unsurprisingly, Creaform’s main market for their product is for manufacturing, whether as part of the rapid prototyping process for product development or for quality control. It also offers manufacturers the possibility of quickly scanning prototypes to check for modifications which are then fed back into conventional CAD software.

However, according to St-Pierre, Handyscan has a number of applications outside the product design department. It is also finding uses in aerodynamic development in motor-racing, where car parts can be scanned both before and after testing to see where any component degradation has taken place.

Its development has also led to a number of surprising applications in both medical and multimedia fields. Creaform is already working with hospitals in the US where Handyscan is being used in the development of prosthetic limbs. For people who have lost part of a limb, the system can scan the leg and then create an accurate 3D model for the development of a custom-made prosthesis that will fit more comfortably.

St-Pierre said that, as a multimedia tool, the device can be useful for museums and art galleries to keep track of their stock. ‘They can scan their artefacts to keep a trace of everything and then create a “virtual” museum of everything, which visitors could then look through on the internet.’

He said that Handyscan could also be used in the future by museums to keep track of any damage that might occur to precious exhibits or artefacts during either storage or transportation. If anything were to happen to a priceless piece of pottery, for example, the CAD database that had been created could then be used to assist restoration work or even to create a millimetre-perfect replica of the original. This system could also help create commercial replicas for the museum shop too, he added.

One of Handyscan’s other key advantages is cost. While at $40,000 (£21,000) it is certainly not cheap, St-Pierre claimed that in conventional systems the tracking arm alone could cost that much with the scanner head itself costing about as much again.

As part of the development work on the Handyscan, Creaform aimed to minimise the number of moving mechanical parts to reduce both weight and cost and to increase its reliability. ‘Even though the heart of the system is extremely complex, we tried to keep the rest of it as simple as possible,’ said St-Pierre.

Time was also spent on making sure that the device was as ergonomic and balanced as possible to make it easy to use and, as it weighs only 980g, Creaform claims that it is extremely comfortable to handle.

According to St-Pierre it is unlikely that the Handyscan will have any direct competitors in the near future. ‘What we have developed is a major technological breakthrough,’ he said. ‘It was such a complicated development process to work out how to make it able to track on its own and be self-stabilising that we don’t expect other companies to be able to copy the Handyscan for a number of years.’