OLBVH: octree linear bounding volume hierarchy for volumetric meshes

We present a novel bounding volume hierarchy for GPU-accelerated direct volume rendering (DVR) as well as volumetric mesh slicing and inside-outside intersection testing. Our novel octree-based data structure is laid out linearly in memory using space filling Morton curves. As our new data structure results in tightly fitting bounding volumes, boundary markers can be associated with nodes in the hierarchy. These markers can be used to speed up all three use cases that we examine. In addition, our data structure is memory-efficient, reducing memory consumption by up to 75%. Tree depth and memory consumption can be controlled using a parameterized heuristic during construction. This allows for significantly shorter construction times compared to the state of the art. For GPU-accelerated DVR, we achieve performance gain of 8.4$$\times $$ × –13$$\times $$ × . For 3D printing, we present an efficient conservative slicing method that results in a 3$$\times $$ × –25$$\times $$ × speedup when using our data structure. Furthermore, we improve volumetric mesh intersection testing speed by 5$$\times $$ × –52$$\times $$ × .

Robot Imitation Learning of Social Gestures with Self-Collision Avoidance Using a 3D Sensor

To effectively interact with people, social robots need to perceive human behaviors and in turn display their own behaviors using social communication modes such as gestures. The modeling of gestures can be difficult due to the high dimensionality of the robot configuration space. Imitation learning can be used to teach a robot to implement multi-jointed arm gestures by directly observing a human teacher’s arm movements (for example, using a non-contact 3D sensor) and then mapping these movements onto the robot arms. In this paper, we present a novel imitation learning system with robot self-collision awareness and avoidance. The proposed method uses a kinematical approach with bounding volumes to detect and avoid collisions with the robot itself while performing gesticulations. We conducted experiments with a dual arm social robot and a 3D sensor to determine the effectiveness of our imitation system in being able to mimic gestures while avoiding self-collisions.

The Trolley Problem Version of Autonomous Vehicles

Introduction:The Trolley problem is a very well-known ethics dilemma about actively killing one or sometimes even more persons in order to save a number of persons. The problem can occur in autonomous vehicles when the vehicle realizes that there is no way to prevent a collision, the computer of the vehicle should analyze which collision is considered to be the least harmful collision.Method and Result:In this paper, we suggest a method to evaluate the likely harmfulness of each sort of collision using Spatial Data Structures and Bounding Volumes and accordingly to decide which course of actions would be the less harmful and therefore should be chosen by the autonomous vehicle.Conclusion:The aim of this paper is to emphasize that the “Trolley Problem” occurs when the human driver is replaced by a robot and if a moral answer is given by an authoritative and legitimate board of experts, it can be coded in autonomous vehicle software.

BOUNDING VOLUMES OF SINGULAR FANO THREEFOLDS

Let $(X,\unicode[STIX]{x1D6E5})$ be an $n$-dimensional $\unicode[STIX]{x1D716}$-klt log $\mathbb{Q}$-Fano pair. We give an upper bound for the volume $\text{Vol}(X,\unicode[STIX]{x1D6E5})=(-(K_{X}+\unicode[STIX]{x1D6E5}))^{n}$ when $n=2$, or $n=3$ and $X$ is $\mathbb{Q}$-factorial of $\unicode[STIX]{x1D70C}(X)=1$. This bound is essentially sharp for $n=2$. The main idea is to analyze the covering families of tigers constructed in J. McKernan (Boundedness of log terminal fano pairs of bounded index, preprint, 2002, arXiv:0205214). Existence of an upper bound for volumes is related to the Borisov–Alexeev–Borisov Conjecture, which asserts boundedness of the set of $\unicode[STIX]{x1D716}$-klt log $\mathbb{Q}$-Fano varieties of a given dimension $n$.

Chaotic analysis of parameters of cardiovascular system in aboriginal and non-aboriginal female population of Ugra

In the 15-th measured phase space of states (m=15) the motion of the state vector in female – representatives of aboriginal (khanty) and non-aboriginal population of Ugra was studied. The parameters xi of the cardiovascular system of groups of women of three ages were ranged bounding volumes VG phase space of states, which are defined as quasi-attractor. These volumes VG determined and compared to the khanty and non-aboriginal population, thus establishing the fun-damental differences in the dynamics of VG: if the natives give almost exponential decrease VG, then it´s population in the age aspect demonstrates a parabolic relationship with at least middle age. It is assumed that a parabola cannot contribute to prolongation of life in general and an increase in the length of the working-age women of Ugra.

Research on the Collision Detection Technology of Coal-Cutting Machinery in Remote Virtual Control

On account of the dangerousness of coal mining, the remote virtual control of coal-cutting machinery is the development direction of coal mine automation, and collision detection is a crucial technology of virtual reality system. In order to solve the problems about through the wall during virtual scene walkthrough in virtual control of coal-cutting machinery, this paper has researched collision detection algorithm, according to the characteristics of coalface and virtual reality system scene, taking advantage of hierarchical bounding volumes algorithm to solve the collision detection problems of coalface in virtual reality system. And it has compiled the algorithm by applying SDK of Quest3D software. Research results show that, realization of the collision detection algorithm has solved scene roaming simulation degree and the speed of the system in coalface virtual scene walkthrough.