The fundamental difference between autonomous robotic assembly and traditional hard automation, currently utilized in large-scale manufacturing production, lies in the specific approaches used in locating, acquiring, manipulating, aligning, and assembling parts. An autonomous robotic assembly manipulator offers high flexibility and high capability to deal with the inherent system uncertainties, unknowns, and exceptions. This paper presents an autonomous mobile manipulator that effectively overcomes inherent system uncertainties and exceptions by utilizing control strategies that employ coordinated control, combine visual and force servoing, and incorporate sophisticated reactive task control. The mobile manipulation system has been demonstrated experimentally to achieve high reliability for a "pegin-hole" type of insertion assembly task that is commonly encountered in automotive wiring harness assembly.

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Active Appearance Models (AAMs) are generative, parametric models that have been successfully used in the past to model deformable objects such as human faces. The original AAMs formulation was 2D, but they have recently been extended to include a 3D shape model. A variety of single-view algorithms exist for fitting and constructing 3D AAMs but one area that has not been studied is multi-view algorithms. In this paper we present multi-view algorithms for both fitting and constructing 3D AAMs.Fitting an AAM to an image consists of minimizing the error between the input image and the closest model instance; i.e. solving a nonlinear optimization problem. In the first part of the paper we describe an algorithm for fitting a single AAM to multiple images, captured simultaneously by cameras with arbitrary locations, rotations, and response functions. This algorithm uses the scaled orthographic imaging model used by previous authors, and in the process of fitting computes, or calibrates, the scaled orthographic camera matrices. In the second part of the paper we describe an extension of this algorithm to calibrate weak perspective (or full perspective) camera models for each of the cameras. In essence, we use the human face as a (non-rigid) calibration grid. We demonstrate that the performance of this algorithm is roughly comparable to a standard algorithm using a calibration grid. In the third part of the paper, we show how camera calibration improves the performance of AAM fitting.A variety of non-rigid structure-from-motion algorithms, both single-view and multi-view, have been proposed that can be used to construct the corresponding 3D non-rigid shape models of a 2D AAM. In the final part of the paper, we show that constructing a 3D face model using non-rigid structure-from-motion suffers from the Bas-Relief ambiguity and may result in a "scaled" (stretched/compressed) model. We outline a robust non-rigid motion-stereo algorithm for calibrated multi-view 3D AAM construction and show how using calibrated multi-view motion-stereo can eliminate the Bas-Relief ambiguity and yield face models with higher 3D fidelity.

Abstract-Traditional industrial robots have been widely used in automotive manufacturing for nearly 30 years. However, there have been very few attempts to automate mobile robotic systems for final assembly operations, despite their potential for high flexibility and capability. This paper focuses on methods of tracking a dynamic moving vehicle that is similar to the vehicle body on a moving assembly line. We have investigated two tracking methods, one using a laser scanner and the other using a visual fiducial marker. We have also studied the tracking performance of a mobile base using the pure pursuit algorithm with low pass filtering. Experimental results are presented to illustrate the remaining main challenges in achieving robotic assembly on moving assembly lines.

The accurate measurement of the orientation of optica l parts and systems is a pressing problem for upcoming space m issions, such as stellar interferometers, requiring the know ledge and maintenance of positions to the sub-arcsecond level. Theodo lites, the devices commonly used to make these measurements, cannot provide the needed level of accuracy. This paper describes the design, construction, and testing of an interferometer system to fill the w idening gap between future requirements and current capabi lities. A Twyman-Green interferometer mounted on a 2 degree of freedom rotation stage is able to obtain sub-arcsecond , gravity-referenced ti It measurements of a sample al ignment cube. Dubbed a 'theoferometer,' this device offers greater ease-of-use, accuracy, and repeatability than conventional methods, making it a suitable 2 1 st-century replacement for the theodol ite.

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