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Item Inverse Kinematics and Kinetics for Virtual Humanoids(The Eurographics Association, 2007) Boulic, Ronan; Kulpa, Richard; Karol Myszkowski and Vlastimil HavranThe present tutorial deals with the use of inverse kinematics and kinetics for postural adaptations of virtual hu- manoids to different kind of constraints. It first proposes an overview of the problematic of this thematic and then of the existing techniques. Then it technically describes two key approaches: the prioritized inverse kinematics for accurate and realistic adaptation and a CCD-like algorithm based on groups for fast and realistic adaptation of hundreds of characters in real-time.Item Egocentric Normalization of Kinematic Path(The Eurographics Association, 2015) Molla, Eray; Boulic, Ronan; B. Solenthaler and E. PuppoWe focus on retargetting the class of movements involving self-interactions onto characters with different size and proportion. Such postures may produce self-collisions and/or alter the intended semantics. We introduce a technique to normalize the spatial relationship vectors between the body parts of the source character. This allows for morphological adaptation of these vectors onto the target characters, hence preserving the semantics in postures with and without body-contact.Item Proactive Steering Toward Oriented Targets(The Eurographics Association, 2005) Boulic, Ronan; John Dingliana and Fabio GanovelliIn this paper we introduce a real-time steering controller ensuring the reach of a (possible mobile) target position and orientation, without requiring to build/update the full trajectory to that target. We name it the funnelling control. The final orientation is achieved through the continuous adjustment of the heading direction. This control mode is proactive in the sense that it anticipates the success/failure of the reach and adjusts the desired speed accordingly. Both features rely on an heterogeneously sampled table of radial-tangential seek angles obtained when the controller reaches a desired position target without prescribed orientation. By construction, the control update has a constant computing cost, even with variable target characteristics. Its low update cost makes it particularly suited for controlling a large number of mobile entities in real-time. The present exposition is made for an obstacle-free context.Item Item Progressive Cartesian Inequality Constraints for the Inverse Kinematic Control of Articulated Chains(The Eurographics Association, 2005) Peinado, Manuel; Boulic, Ronan; Callennec, Benoit Le; Meziat, D.; John Dingliana and Fabio GanovelliWe propose an Inverse Kinematic Control architecture capable of handling tasks that are expressed in terms of inequality constraints in the Cartesian space. These inequality constraints are progressive in the sense that their influence manifests itself in a zone of finite thickness by damping the progression toward the strict limit of the constraint. We show how to enforce this family of constraints in a two stage process with our prioritized IK sheme. Various examples highlight the potential of this approach for managing complex articulated chains in cluttered environments where obstacles are modelled with this type of constraints.