For decades, researchers have tried to create holographic displays with the aim of displaying 3D objects that can float in the air. Here’s the latest from researchers in Canada and Brazil who created a spherical display, called Spheree, that lets you gesture and interact with 3D floating projected images. The project was on display at SIGGRAPH 2014 in Vancouver presenting their work through a paper in the IEEE Spectrum. In their own words, this is the first display, “capable of projecting uniform, high resolution pixels on a spherical surface.”
Multiple smaller pico projectors are calibrated together through their FastFusion system, creating a seamless display which uses a standard webcam to automatically blend and calibrate the system. The demonstrations include an interactive snow globe which is a 3D animation of a popular winter seasonal image of a house, snow and train moving around the house. “In one demonstration, viewers have the sensation of staring into a snow globe that they can control with simple gestures from any angle,” said IEEE Spectrum. Another fun application includes 3D sculpting using pointing and bi-manual gestures. You can even take the sculpted piece and send it to the 3D printer. Gesture support include moving, rotating, sculpting and painting objects.
The authors explain that the Spheree is completely scalable with their system, enabling Spheree’s that can go as large as required. The team has even tested a 20-in diameter, eight projector unit as well. Head tracking support allows Spheree to display a prospectively correct view of the object inside, making it look like it’s floating in thin air within the globe. In fact, according to the authors, Spheree also uses six infrared cameras to track the movement of special headbands worn by viewers. The data the cameras feed to a computer constantly provide perspective-corrected virtual scenes based on a viewer’s position with respect to the globe.”
Awesome work. Here’s a related project from years past:
Spheree illustrates that calibrated, multiple projector spherical displays
represent the future of interactive, scalable, high resolution non-planar displays.
HOW IT WORKS
We developed a novel multiple pico-projector system that automatically calibrates and blends using a camera+projector approach. This creates a uniform pixel space on the surface of the sphere.
Our auto-calibration algorithm uses a spherical modification of [Teubl et al. 2012], which uses a simple webcam. This same webcam is used to calculate the parametrization of the spherical screen for the correct view-point rendering of a scene from the head-coupled viewer.
Spheree is highly scalable allowing as many projectors as needed for virtually any sphere size. Our spherical display design has no corners, hence no singularities in blending, and provides uniform pixel density across the whole sphere. Additionally, no mirrors are used so there are no blind spots. We only use lenses that come with the pico-projectors, rather than special ones such as fish-eye lenses, simplifying rendering.
Spheree supports bi-manual gesture, hands-free and moving-the-display interactions. We coupled Spheree to a 3D modelling package, Blender, to illustrate its use in a 3D modelling workflow. People can use a 3D modelling environment or capture real objects, such as designs moulded with clay, and easily put them inside Spheree.
We have tested a 20" diameter, eight pico-projector and a 7", four pico-projector Sphere. The 20" Spheree allows participants to experience and interact with 1:1 models of human sized objects. The small spheree can be held in your hands; thus, users are able to pick it up and interact with the models inside.
Spheree: A 3D Perspective-Corrected Interactive Spherical Scalable Display
Spheree is a personal spherical display that arranges multiple blended and calibrated mini-projectors to transform a translucent globe into a high-resolution perspective-corrected 3D interactive display. It tracks both the user and Spheree to render user-targeted views onto the surface of the sphere. This provides motion parallax, occlusion, shading, and perspective depth cues to the user. One of the emerging technologies that makes Spheree unique is that it uses multiple mini-projectors, calibrated and blended automatically to create a uniform pixel space on the surface of the sphere. The calibration algorithm allows for as many projectors as needed for virtually any size of sphere, providing a linear scalability cost for higher-resolution spherical displays.
Spheree does not have any seams or blind spots, so rendered scenes are not occluded, and the display can support stereo 3D experiences. Using touch and gesture, it supports tangible interactions such as moving, rotating, sculpting, and painting objects, in addition to object manipulation. Computer-generated 3D models or 3D models of real objects can be imported into Spheree. Once objects are modified within Spheree, its workflow supports export of the modified model to work easily with other applications.
Two Spherees (different sizes) are presented at SIGGRAPH 2014 Emerging Technologies, to demonstrate that calibrated multiple-projector spherical displays represent a future of interactive, scalable, high-resolution, non-planar displays.
It's official: we're well on the way to a true 3D display. This one, called Spheree, is the work of a team of researchers working together from the University of São Paulo, Brazil, and the University of British Columbia, Canada, and it's mesmerising to behold.
Like its name suggests, it's in the shape of a translucent sphere; inside, the viewer can see animations and images that appear to float in the centre; as the viewer moves around, they can see other sides of the object as their perspective changes.
And it's all based on optical illusion. Packed inside the Spheree are multiple mini-projectors, which shine the images onto the interior surface of the sphere. Special software designed by the team blends the projector images together for a single, seamless image.
Because it is projected onto the surface of the globe, the next problem is the viewer's position in relation to Spheree. If the user is on one side and walks to the other, the view would usually distort or be obscured. For this reason, the device integrates motion-tracking software for user-targeted views: as the user moves around the sphere, the projected image follows, automatically correcting for perspective, appearing to stay in one place while the viewer moves around.
To do this, it uses infrared cameras that track a headband worn by the user.
"One of the emerging technologies that makes Spheree unique is that we use multiple mini-projectors, calibrated and blended automatically to create a uniform pixel space on the surface of the sphere," the team wrote.
"The calibration algorithm we developed allows for as many projectors as needed for virtually any size of sphere, providing a linear scalability cost for higher-resolution spherical displays. Spheree does not have any seams or blind spots, therefore rendered scenes are not occluded and the display can support stereo 3D experiences."
Although small projectors are usually low-resolution, the team circumvented this using a scalable multi-projector system called FastFusion, which automatically calibrates aligned projectors to blend separate projections.
But it's not just for passive viewing: using a leap motion gesture controller, the Spheree is able to integrate motion control, allowing users to interact with the models and images therein with their hands. Much like a sculptor can push, pull, turn, and sculpt a piece of clay, 3D modellers can directly create 3D models with their hands using software such as Blender via a connected computer.
The team demonstrated two versions of the Spheree at SIGGRAPH 2014 in Vancouver, Canada, earlier this month: a smaller 18cm display and a larger 51cm display.