Le contrat de concession commerciale et le libre marché

This paper deals with the exclusive sale contract or solus agreement. Its first part identifies some characteristic features of this type of agreement, which quite often is not only aimed at regulating the exercise of trade, but also serves as a technique of market organization and economic power concentration. The impact of the increasing currency of such commercial practices on the free market justifies consideration of the various forms of control that can be exercised by public authorities in order to preserve free competition. Control can be achieved through the judiciary applying concepts such as public order in civil law or public policy at common law. However, in view of the courts' reluctance to interfere with such instances of private economic power and their indifference towards the economic inequities inherent in such agreements for the distributor, legislative intervention has become necessary to protect the free market. Thus the Combines Investigation Act was amended in 1976 to allow regulation of commercial practices such as refusal to deal, consignment selling, exclusive dealing, market restriction and tied selling

L'harmonisation du droit de la vente: l'influence de la Convention de Vienne sur l'évolution et l'harmonisation du droit des provinces canadiennes

La Convention de Vienne sur les contrats de vente internationale de marchandises est le résultat de difficiles compromis de la part de pays appartenant à différentes familles juridiques ; plusieurs de ses dispositions reflètent de tels compromis entre systèmes de droit civil et de common law. Sur le plan interne canadien, retrouve-t-on une telle tendance à l'harmonisation des règles du droit de la vente de marchandises en droit civil et en common law ? Dans quelle mesure ces compromis à l'échelle internationale ont-ils influé sur le projet de Code civil du Québec de même que le Uniform Sale of Goods Act, que la Conférence sur l’uniformisation des lois aproposé aux provinces de common law en vue d'en arriver à l'harmonisation du droit de la vente entre celles-ci ? L'inclusion dans la Convention de Vienne d'une disposition créant une obligation de bonne foi fut en particulier l'occasion de longs débats. Si l'inclusion dans le projet de Code civil du Québec d'une disposition reconnaissant expressément le principe de bonne foi ne soulève pas de controverse, une reconnaissance expresse du principe de bonne foi, dans le Uniform Sale of Goods Act soulève cependant encore de longs débats. L'adhésion du Canada à la Convention des Nations Unies sur les contrats de vente internationale de marchandises contribuera à harmoniser le droit applicable à ce type de transaction. Mais, on ne peut malheureusement pas parler d'harmonisation pour ce qui est des ventes interprovinciales de marchandises au Canada.The Vienna Convention on contracts for the international sale of goods is the product of arduous compromises on the part of countries belonging to differing legal traditions. Several of its provisions reflect such compromises between the civil law and common law systems. In domestic matters in Canada, do we find a similar trend towards a harmonization of rules governing the sale of goods in civil law and common law ? To what extent have these international compromises influenced the proposed Civil Code of Quebec and the Uniform Sale of Goods Actthat the Uniform Legislation Conference proposed to the common law provinces so as to harmonize legal practices amongst themselves ? The inclusion in the Vienna Convention of a provision creating an obligation of good faith was the source of long debates. If the inclusion in the Civil Code of Quebec of a provision expressly recognizing the principe of good faith does not raise any controversy, an express recognition of the principle of good faith in the Uniform Sale of Goods Act does, to the contrary, still provoke long debates. The adhesion of Canada to the United Nations convention on the international sale of goods will contribute to harmonizing the law applicable to this type of transaction. Nonetheless, we still cannot speak of harmonization in the case of interprovincial sale of goods in Canada

Control of VTOL Vehicles with Thrust-direction Tilting

An approach to the control of a VTOL vehicle equipped with complementary thrust-direction tilting capabilities that nominally yield full actuation of the vehicle's position and attitude is developed. The particularity and difficulty of the control problem are epitomized by the existence of a maximal thrust-tilting angle which forbids complete and decoupled control of the vehicle's position and attitude in all situations. This problem is here addressed via the formalism of primary and secondary objectives and by extending a solution previously derived in the fixed thrust-direction case. The proposed control design is also illustrated by simulation results involving a quadrotor UAV with all propellers axes pointing in the same monitored tilted direction

Nonlinear Feedback Control of Axisymmetric Aerial Vehicles

We investigate the use of simple aerodynamic models for the feedback control of aerial vehicles with large flight envelopes. Thrust-propelled vehicles with a body shape symmetric with respect to the thrust axis are considered. Upon a condition on the aerodynamic characteristics of the vehicle, we show that the equilibrium orientation can be explicitly determined as a function of the desired flight velocity. This allows for the adaptation of previously proposed control design approaches based on the thrust direction control paradigm. Simulation results conducted by using measured aerodynamic characteristics of quasi-axisymmetric bodies illustrate the soundness of the proposed approach

Modeling for Control of Symmetric Aerial Vehicles Subjected to Aerodynamic Forces

This paper participates in the development of a unified approach to the control of aerial vehicles with extended flight envelopes. More precisely, modeling for control purposes of a class of thrust-propelled aerial vehicles subjected to lift and drag aerodynamic forces is addressed assuming a rotational symmetry of the vehicle's shape about the thrust force axis. A condition upon aerodynamic characteristics that allows one to recast the control problem into the simpler case of a spherical vehicle is pointed out. Beside showing how to adapt nonlinear controllers developed for this latter case, the paper extends a previous work by the authors in two directions. First, the 3D case is addressed whereas only motions in a single vertical plane was considered. Secondly, the family of models of aerodynamic forces for which the aforementioned transformation holds is enlarged.Comment: 7 pages, 4 figure

Observer design for position and velocity bias estimation from a single direction output

This paper addresses the problem of estimating the position of an object moving in $R^n$ from direction and velocity measurements. After addressing observability issues associated with this problem, a nonlinear observer is designed so as to encompass the case where the measured velocity is corrupted by a constant bias. Global exponential convergence of the estimation error is proved under a condition of persistent excitation upon the direction measurements. Simulation results illustrate the performance of the observer.Comment: 6 pages, 6 figure

Une approche pour la synthèse et l'analyse de la commande des robots manipulateurs rigides

Disponible dans les fichiers attachés à ce documen

Time-varying feedback stabilization of nonholonomic car-like mobile robots

Many nonholonomic mechanical systems, such as car-like mobile robots, are controllable but cannot be stabilized to given positions and orientations by using smooth pure-state feedback control. However, as shown in [18], such systems may still be stabilized by using smooth time-varying feedbacks, i.e. feedbacks which explicitly depend on the time-variable. This possibility is here applied to the stabilization of a class of nonlinear systems whose equations encompass simple car models. A set of stabilizing smooth time-varying feedbacks is derived and simulation results are given