Motion illusions for defence

防御运动错觉

• 批准号: BB/V001388/1
• 负责人: Christos Ioannou
• 金额: $ 55.05万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FV001388%2F1
• 关键词: Motion; illusions; defence

High-contrast colour patterns, such as black and white stripes, can move in a way that interferes with how animals, including humans, detect and perceive motion. For instance, objects become blurred when moving quickly enough, and when the diagonally-striped poles outside barber shops rotate horizontally they create an illusion of the stripes moving vertically. In our project, we aim to understand whether and how these 'dazzle' illusions are used by prey to escape their predators. While the colour patterning of animals is one of their most obvious features, dazzle colouration must be paired with particular ways of moving to be effective; for the first time we will quantify both colour and movement in our study. Obtaining an understanding of how dazzle colouration operates in the real world will help explain the enormous diversity of conspicuous colour patterns displayed by animals. There is also practical application in understanding how motion illusions can be exploited, or indeed minimised depending on the need, in safety and defence industries.Whilst the idea of dazzle colouration was proposed over a century ago and was potentially exploited by Allied ships in WWI and WWII to avoid torpedo-wielding enemy U-boats, it has only received serious scientific interest over the past decade. Even then, studies have almost exclusively relied on proxies for real predators by using humans 'attacking' computer-animated prey that have colour and movement patterns not necessarily found in nature. A better understanding of how dazzle illusions may actually operate in nature, and thus how they may be exploited in real-world scenarios, ultimately requires studying natural systems in the same contexts and environmental conditions within which they have evolved.In our project we will exploit the extraordinary diversity of colour patterns seen in fish to determine whether different types of colour pattern are linked to how fish move. We will then test whether these motion-colour combinations maximise the production of dazzle illusions and how this benefits prey fish attacked by real predators, and whether the dynamic nature of dazzle colouration makes it harder for predators to learn to counteract illusions and defeat their illusionist prey. We predict that dazzle-coloured prey benefit by being camouflaged (i.e. reducing detection from predators), reducing the frequency of attacks by confusing predators, and reducing successful capture after they are attacked by misdirecting the attacks of predators. We will use mathematical models of the motion-processing cells within animal visual systems to objectively quantify, from a predator's perspective, illusions across multiple prey fish species. Initial data from four species of closely-related zebrafish that display very different colour patterns suggest that by just changing the orientation of stripes, fish can either become camouflaged or create an illusion of movement in a different direction to true motion, which could affect the ability of predators to accurately target their prey. We will test whether these illusions are beneficial for prey by allowing natural predators to hunt and attack realistic robotic prey that closely match the illusionist's colouration, shape and movement. This will be the definitive study that tests whether motion illusions occur in nature, and whether they can create enough interference in the visual system of predators to benefit real animals. The results from our project may have applications for low-tech military confrontations that use visual systems to intercept moving targets, and also for road-user safety where the blending of stripes at high speeds can be exploited by stripe patterns across the road or on emergency vehicles under scenarios that require a careful perception of speed by pedestrians, cyclists and motorists.

高对比度的彩色图案，如黑白条纹，可以以一种干扰动物（包括人类）检测和感知运动的方式移动。例如，当物体移动得足够快时，物体会变得模糊，当理发店外的对角线条纹杆水平旋转时，它们会产生条纹垂直移动的错觉。在我们的项目中，我们的目标是了解这些“炫目”错觉是否以及如何被猎物用来逃离它们的捕食者。虽然动物的色彩图案是它们最明显的特征之一，但炫目的色彩必须与特定的移动方式相搭配才能有效；这是我们第一次在研究中量化颜色和运动。了解炫目色彩在现实世界中是如何运作的，将有助于解释动物所展示的炫目色彩模式的巨大多样性。在安全和国防工业中，也有实际应用，可以理解如何利用运动错觉，或者根据需要将其最小化。虽然在一个多世纪前就提出了炫目色彩的想法，并在第一次世界大战和第二次世界大战中被盟军船只利用，以避开使用鱼雷的敌人u型潜艇，但直到过去十年，它才受到严肃的科学关注。即便如此，研究几乎完全依赖于真实捕食者的代理，通过人类“攻击”计算机动画的猎物，这些猎物具有不一定在自然界中发现的颜色和运动模式。为了更好地理解炫目幻觉在自然界中是如何运作的，以及它们如何在现实世界中被利用，最终需要在它们进化的相同背景和环境条件下研究自然系统。在我们的项目中，我们将利用鱼类身上不同的颜色模式来确定不同类型的颜色模式是否与鱼类的运动方式有关。然后，我们将测试这些运动-颜色组合是否能最大限度地产生令人眼花缭乱的错觉，以及这对被真正的捕食者攻击的猎物有何好处，以及眼花缭乱颜色的动态特性是否会使捕食者更难学会抵消错觉并击败他们的错觉猎物。我们预测，色彩艳丽的猎物受益于伪装（即减少被捕食者发现），通过迷惑捕食者减少攻击频率，并通过误导捕食者的攻击来减少攻击后的成功捕获。我们将使用动物视觉系统中运动处理细胞的数学模型，从捕食者的角度客观地量化多种猎物鱼类的错觉。来自四种关系密切的斑马鱼的初步数据表明，通过改变条纹的方向，鱼要么伪装起来，要么制造一种与真实运动方向不同的运动错觉，这可能会影响捕食者准确瞄准猎物的能力。我们将测试这些幻觉是否对猎物有益，让自然捕食者捕猎和攻击与魔术师的颜色、形状和动作非常相似的逼真的机器人猎物。这将是一项决定性的研究，它将测试运动错觉是否在自然界中发生，以及它们是否能对捕食者的视觉系统产生足够的干扰，从而使真正的动物受益。我们项目的结果可能会应用于低技术含量的军事对抗，使用视觉系统拦截移动目标，也可以用于道路使用者的安全，高速下的条纹混合可以被马路上的条纹图案所利用，或者在需要行人、骑自行车的人和驾车者仔细感知速度的情况下，在紧急车辆上。