We are interested in producing a 3D deformable model of the human hand, for use in a tracking application. Statistical methods can be used to build such a model from a set of training examples; however, a key requirement for this is the collection of landmark coordinate data from these training examples. To produce a good model, hundreds of landmarks are required from each example; collecting t...

This paper presents an active approach for part-based object detection, which optimizes the order of part filter evaluations and the time at which to stop and make a prediction. Statistics, describing the part responses, are learned from training data and are used to formalize the part scheduling problem as an offline optimization. Dynamic programming is applied to obtain a policy, which balanc...

Deformable models are used extensively in image processing, computer vision, and medical imaging applications, particularly to delineate object boundaries. Problems associated with initialization and poor convergence to boundary concavities, however, have limited their utility. This chapter presents an external force for deformable models, largely solving both problems. This external force, whi...

Recovery of unstructured 3D data with deformable models has been the subject of many studies over the last ten years. In particular, in medical image understanding, deformable models are useful to get a precise representation of anatomical structures. However, general deformable models involve large linear systems to solve when dealing with high resolution 3D images. The advantage of parametric...

Contact mechanics plays an important role in the design, performance analysis, simulation, and control of legged robots. The Hunt–Crossley model and the Coulomb friction model are often used as black-box models with limited consideration of the properties of the terrain and the feet. This paper analyzes the foot–terrain interaction based on the knowledge of terramechanics and reveals the relati...

Using a force feedback device within the framework of deformable object simulation remains difficult because of the incompatibility between the computation time needed by realistic deformable models and high refresh frequencies necessary for real-time haptic rendering. Giving the user a good haptic sensation requires refreshing the applied forces at least ten times more often than for giving a ...

Deformable models often require some degree of user-interaction to produce an accurate segmentation of the feature object. We propose an automatic deformable surface for segmenting the femur from magnetic resonance volumes of the knee. In order to overcome the limitations of many existing deformable models, probabilistic labelling is used to drive the deformation process, together with a surfac...

In this paper we describe a test-bed we have developed for simulation of abdominal trauma surgery. The abdominal surgery scene is highly complex and contains many layers of deformable organs. Representing this layered and deformable anatomy with models that can interact, be probed and cut presents a unique challenge. We have met this challenge by applying a variety of technology advances in def...

This article surveys deformable models, a promising and vigorously researched computer-assisted medical image analysis technique. Among model-based techniques, deformable models offer a unique and powerful approach to image analysis that combines geometry, physics and approximation theory. They have proven to be effective in segmenting, matching and tracking anatomic structures by exploiting (b...