In 1997, Azuma published a survey on augmented reality (AR). Our goal is to complement, rather than replace, the original survey by presenting representative examples of the new advances. We refer one to the original survey for descriptions of potential applications (such as medical visualization, maintenance and repair of complex equipment, annotation, and path planning); summaries of AR system characteristics (such as the advantages and disadvantages of optical and video approaches to blending virtual and real, problems in display focus and contrast, and system portability); and an introduction to the crucial problem of registration, including sources of registration error and error-reduction strategies.

https://www.cc.gatech.edu/~blair/papers/ARsurveyCGA.pdf

Recent advances in augmented reality

We are on the verge of ubiquitously adopting Augmented Reality (AR) technologies to enhance our percep- tion and help us see, hear, and feel our environments in new and enriched ways. AR will support us in fields such as education, maintenance, design and reconnaissance, to name but a few. This paper describes the field of AR, including a brief definition and development history, the enabling technologies and their characteristics. It surveys the state of the art by reviewing some recent applications of AR technology as well as some known limitations regarding human factors in the use of AR systems that developers will need to overcome.

/pdf/a-survey-of-augmented-reality-technologies-applications-and-3d9hf1tnc4.pdf

A Survey of Augmented Reality Technologies, Applications and Limitations

This survey summarizes almost 50 years of research and development in the field of Augmented Reality AR. From early research in the1960's until widespread availability by the 2010's there has been steady progress towards the goal of being able to seamlessly combine real and virtual worlds. We provide an overview of the common definitions of AR, and show how AR fits into taxonomies of other related technologies. A history of important milestones in Augmented Reality is followed by sections on the key enabling technologies of tracking, display and input devices. We also review design guidelines and provide some examples of successful AR applications. Finally, we conclude with a summary of directions for future work and a review of some of the areas that are currently being researched.

/pdf/a-survey-of-augmented-reality-2ce6xet7y5.pdf

A Survey of Augmented Reality

A safety critical, time sensitive data system for projecting safety/mission critical data onto a display pair of Commercial Off The Shelf (COTS) light weight projection glasses or monocular creating an immersive omnidirectional HUD (Heads Up Display) system with 6 degrees of freedom movement with user immersion and user inputs & outputs. The system includes the display, haptic glove, haptic suit, vestibular interface, temperature emulation, smell emulation, and omnidirectional sound, the workstation, the application software, and inputs containing the safety/mission critical information (Current User Position, Total Collision Avoidance System—TCAS, Global Positioning System—GPS, Magnetic Resonance Imaging—MRI Images, CAT scan images. Weather data. Military troop data, real-time space type markings etc.). The workstation software processes the incoming safety/mission critical data and converts it into a three dimensional space for the user to immerse into the environment. Selecting any of the images may display available information about the selected item or may enhance the image, or moving hand or body will generate enhanced environmental perception & awareness, as well as inputs and outputs. Predicted position vectors may be displayed as well as 3D terrain.

Computer-aided system for 360º heads up display of safety/mission critical data

A real-time structured light depth extraction system includes a projector for projecting structured light patterns onto an object of interest. A camera positioned off-axis from the projector samples light reflected from the object synchronously with the projection of structured light patterns and outputs digital signals indicative of the reflected light. An image processor/controller receives the digital signals from the camera and processes the digital signals to extract depth information of the object in real time.

Methods and systems for real-time structured light depth extraction and endoscope using real-time structured light depth extraction

We present the design and a prototype implementation of a three-dimensional visualization system to assist with laparoscopic surgical procedures. The system uses 3D visualization, depth extraction from laparoscopic images, and six degree-of-freedom head and laparoscope tracking to display a merged real and synthetic image in the surgeon’s video-see-through head-mounted display. We also introduce a custom design for this display. A digital light projector, a camera, and a conventional laparoscope create a prototype 3D laparoscope that can extract depth and video imagery.

/pdf/augmented-reality-visualization-for-laparoscopic-surgery-ln800qx277.pdf

Augmented Reality Visualization for Laparoscopic Surgery

The pocketing operation is a fundamental procedure in NC machining. Typical pocketing schemes compute uniform successive offsets or parallel cuts of the outline of the pocket, resulting in a toolpath with C 1 discontinuities. These discontinuities render the toolpath quite impractical in the context of high speed machining (HSM). This work addresses and fully resolves the need for a C 1 continuous toolpath in HSM and offers MATHSM, a C 1 continuous toolpath for arbitrary C 1 continuous pockets. MATHSM automatically generates a C 1 continuous toolpath that consists of primarily circular arcs while maximizing the radii of the generated arcs and, therefore, minimizing the exerted radial acceleration. MATHSM is especially suited for machining of elongated narrow pockets.

/pdf/mathsm-medial-axis-transform-toward-high-speed-machining-of-546z1u4lqt.pdf

MATHSM: medial axis transform toward high speed machining of pockets

An iterative spline interpolation method for a numerically-controlled machine tool device is disclosed The non-uniform rational B-spline (NURBS) curve inputted to the numerically-controlled machine tool is interpolated with a constant step size providing the ability to maintain a controlled velocity to within a specified tolerance In addition, the distance left to travel on the curve is obtained by a unique spline node-based approximation method providing accurate acceleration and deceleration control The rational spline interpolation method provides significant reduction in the amount of data required to produce smoothly machined pieces while providing accurate machining of conic sections not possible by previous spline interpolation methods

Method and system for spline interpolation, and their use in CNC

Sketch-N-Make is a prototype system that enables individuals to create dimensioned designs quickly for a restricted, but broadly useful, domain of machined metal and plastic prismatic parts. Process plans, xturing, tool selection, feeds and speeds, and toolpaths are automatically generated from the designs allowing parts to be manufactured on a machining center with the aid only of a technician who prepares and loads the stock and cutting tools. The system employs a gestural interface that exploits familiar pencil sketching paradigms to allow users to create and manipulate geometry without specifying the details required for manufacturing. The system transforms the geometry into a highlevel feature-based model that represents the geometry and additional information from which machining features are derived. The sketching interface has mechanisms to constrain and parameterize 3D model geometry in ways required for precise part design and design iteration. The user can modify iteratively the geometric representation causing the system to automatically update the feature-based model accordingly. Then the system generates the necessary machining operations to manufacture the geometry on a machining center according to a family of process plans. The synergy between the choices for part domain, user interface, and process plan family helps provide a smooth and rapid

/pdf/sketch-n-make-automated-machining-of-cad-sketches-1i5hbhwfrg.pdf

Sketch-n-make: automated machining of cad sketches

http://asmedigitalcollection.asme.org/IDETC-CIE/proceedings-pdf/doi/10.1115/DETC1993-0374/6666638/35_1_detc1993-0374.pdf

Samuel Drake

Papers

Augmented Reality Visualization for Laparoscopic Surgery

MATHSM: medial axis transform toward high speed machining of pockets

Method and system for spline interpolation, and their use in CNC

Sketch-n-make: automated machining of cad sketches

Reconstruction of Sculptured Surfaces Using Coordinate Measuring Machines