Reactive direction control for a mobile robot: A locust-like control of escape direction emerges when a bilateral pair of model locust visual neurons are integrated

Locusts possess a bilateral pair of uniquely identifiable visual neurons that respond vigorously to the image of an approaching object. These neurons are called the lobula giant movement detectors (LGMDs). The locust LGMDs have been extensively studied and this has lead to the development of an LGMD model for use as an artificial collision detector in robotic applications. To date, robots have been equipped with only a single, central artificial LGMD sensor, and this triggers a non-directional stop or rotation when a potentially colliding object is detected. Clearly, for a robot to behave autonomously, it must react differently to stimuli approaching from different directions. In this study, we implement a bilateral pair of LGMD models in Khepera robots equipped with normal and panoramic cameras. We integrate the responses of these LGMD models using methodologies inspired by research on escape direction control in cockroaches. Using ‘randomised winner-take-all’ or ‘steering wheel’ algorithms for LGMD model integration, the khepera robots could escape an approaching threat in real time and with a similar distribution of escape directions as real locusts. We also found that by optimising these algorithms, we could use them to integrate the left and right DCMD responses of real jumping locusts offline and reproduce the actual escape directions that the locusts took in a particular trial. Our results significantly advance the development of an artificial collision detection and evasion system based on the locust LGMD by allowing it reactive control over robot behaviour. The success of this approach may also indicate some important areas to be pursued in future biological research

The ripple effects of online marketplace bans

The strive for tighter control of distribution, quality and price - has led an increasing number of producers to include restrictions on the use of online marketplaces in their selective distribution agreements. This paper considers the effects of such restrictions and the legal approach they call for. While acknowledging the legitimacy of proportionate restrictions on distribution, the article illustrates how an absolute ban on the use of online marketplaces may have a detrimental effect on market transparency, price competition, entry and expansion. The discussion illustrates how the legitimate interests of producers may be protected through less onerous means, without the increase in consumers’ search costs and the dampening of price competition. With that in mind, it is argued that these restrictions should be analysed on a case-by-case basis and should not benefit from the Vertical Block Exemption. Furthermore, the article considers whether absent proportionality and objective justification, the harmful effect of online marketplace bans, justifies their condemnation as anticompetitive by object

BUYING ALLIANCES AND INPUT PRICE FIXING: IN SEARCH OF A EUROPEAN ENFORCEMENT STANDARD

This article considers the welfare implications of input price fixing and the enforcement standard to be applied to these arrangements. It explores the way in which European competition law approaches input price fixing, the scope of the object-based approach and the instances in which effects-based analysis may be used in the appraisal. In doing so, the article sets to clarify the legal approach to price fixing of a procured input. It outlines a possible benchmark for the assessment of input price fixing, with the aim of sharpening the dividing line between instances that restrict competition by object, and those that necessitate consideration of effects. © The Author (2012). Published by Oxford University Press. All rights reserved

Research handbook on international competition law

'Some 30 leading scholars, academics and practitioners have contributed 22 formidably thoughtful and readable articles to this scholarly and topical book on competition law. . . this book should be of abiding interest to competition lawyers everywhere as well as scholars, academics and competition officials and policymakers in trading nations. The subject matter is international and so is the book's utility and appeal. - Phillip Taylor MBE and Elizabeth Taylor, The Barrister Magazine. © Ariel Ezrachi 2012. All rights reserved

Merger control and cross-border transactions: A pragmatic view on cooperation, convergence and what is in between

Volume: 7Start Page: 157End Page: 16