基于感兴趣区域的螺栓位姿及尺寸检测研究

为了提高工业生产中螺栓定位抓取的效率和准确性,提出基于感兴趣区域的螺栓位姿及尺寸检测方法。首先利用YOLOv5目标识别算法对螺栓目标进行识别,将识别出的目标区域截取为感兴趣区域。再利用中值滤波和二值化方法对ROI进行预处理,采用Canny改进算法检测目标轮廓。通过最优拟合直线算法获取螺栓的倾斜角度,并用矩特征算法求解出螺栓重心位置。最后采用霍夫两直线段最短距离算法检测螺栓直径。经过实验验证采用YOLOv5目标识别算法的识别准确率达到92.7%,螺栓倾斜角度的检查误差为±1.2°,螺栓直径的检测误差率为±5.5%,实现了对螺栓位姿和尺寸的识别。

Hawking Radiation from a Non-static Black Hole

A method exactly determining an event horizon and its temperature in a nonstatic space-time is proposed.Using the generalised Tortoise coordinate,we give exact location of event horison and exact Hawking temperature for a general spherically symmetric evaporating black hole.