Enschede, Netherlands (July 2018)—Xsens, innovator in professional inertial sensor and 3D motion tracking, is applying its technology to a new venture by construction engineering company Dura Vermeer and augmented reality software developer Recreate—the Engineering Building Mixed Reality (EBMR) helmet. The helmet provides (for the first time) a 3D, real-time, holographic rendering of an architect’s plan, overlaid on the user’s view of the building site. Standing on an empty building site, the user can see the structure correctly positioned, as though it has already been built.
The construction industry has to deal with the variances between the ideal plan on paper—in the form of an architect’s drawings—and the reality on the ground. The architect’s design is a vision, but the job of realizing this vision is the builder’s. For centuries, the main way in which architects have communicated their vision to builders is in the form of a plan, or drawings—a 2D, abstract representation of 3D reality. Even today, as digital systems have replaced paper-based methods in so many domains, builders are still tied to computer renderings of an architect’s plan in the form of drawings, which are still 2D when viewed on a display screen. Mentally projecting a flat, abstract representation onto 3D reality, or imagining how the finished structure will look on-site before a single brick has been laid, calls for skill, judgement and interpretation on the part of building professionals. Inevitably, this creates a scope for error, miscalculation and miscommunication between members of a construction project’s team. The development of the EBMR helmet is a remarkable technical achievement, and it depends on an advanced combination of cutting-edge hardware and software technologies.
Dura Vermeer brought to the EBMR project some 160 years of experience in the construction industry. It knows intimately the difficulty of translating an architect’s drawing into a detailed, step-by-step construction plan, and of co-ordinating the implementation of the construction plan across large teams sometimes consisting of hundreds of builders. Together with the knowledge of the development team of Recreate, who have been working with technologies, such as virtual, augmented and mixed reality for years, software has been developed to visualize 3D models with the Microsoft HoloLens. The master document, which guides the management of construction projects, such as those undertaken by Dura Vermeer, is the architect’s blueprint. But the blueprint is not the same thing as an instruction to a builder. For instance, an architect’s drawing might call for a wall to be built. The builder needs to know exactly where the hole for the foundations needs to be dug. A drawing on paper or on a computer cannot point to a spot in the mud and say, "Dig your hole here."
The EBMR helmet can. It provides a real-world projection of the drawing so that a builder can walk around a site and see exactly where each element of the structure will go. Using ultra-accurate satellite positioning data, the helmet knows exactly where the user is on the surface of the earth. From the drawings, it knows exactly where on the surface of the earth the structure is to be built. It can then build the structure in a virtual reality and present it to the user, accurately positioned and oriented. And because it is presented holographically, the structure is overlaid on the user’s view of the site in front of them—a mixed-reality display. The EBMR helmet has already been used in pilot projects, such as the construction by Dura Vermeer of a bridge in The Netherlands, and has provided three valuable benefits:
- Time saving—The helmet enables construction and site managers to make faster and better decisions about the sequencing of tasks; the allocation of assets, such as construction equipment; and the procurement and storage of materials. This leads to a reduction of wasted time, assets and materials.
- Cost saving—The EBMR helmet is so precise that it can be used to make on-site measurements that would previously have required the services of a professional surveyor. Now, such measurements can be taken by ordinary members of the construction crew. Because the use of the helmet also reduces the potential for mistakes, there is less requirement for costly and time-consuming rework
- Quality improvement—The EBMR helmet eliminates the requirement for judgement and interpretation of the architect’s drawings. When builders can look at the site and see what needs to be built in the location where it needs to be built, their work tends to more exactly match the architect’s intention, with zero defects or variances
To provide the capabilities of the EBMR helmet, Dura Vermeer and Recreate required four main hardware elements:
- A holographic projector—This is a Microsoft HoloLens device mounted at the front of the helmet. The Hololens is the world’s most widely used holographic device for professional applications.
- A positioning system—This is a global navigation satellite system (GNSS) receiver mounted at the top of the helmet. GNSS receivers are small semiconductor-based modules and are commonly used in vehicles and mobile phones to support navigation and mapping applications. The EBMR helmet uses a precise GNSS receiver to provide accurate positioning co-ordinates.
- A battery power supply—The battery needs to provide sufficient capacity to power the device for a whole day between charges, as charging on-site might not always be possible.
- An Xsens Inertial Measurement Unit (IMU)—This is a type of motion sensor module, which provides orientation and heading information. Because of the IMU, the helmet knows which direction the user is facing and the position of the head. In navigation terminology, this positioning information is known as pitch, roll and yaw. The heading information is a compass reading relative to magnetic North.