Page 1 Next

Displaying 1 – 20 of 39

Showing per page

On Carnot's theorem in time dependent impulsive mechanics.

Stefano Pasquero (2005)

Extracta Mathematicae

We show that the validity of the Carnot's theorem about the kinetic energy balance for a mechanical system subject to an inert impulsive kinetic constraint, once correctly framed in the time dependent geometric environment for Impulsive Mechanics given by the left and right jet bundles of the space-time bundle N, is strictly related to the frame of reference used to describe the system and then it is not an intrinsic property of the mechanical system itself. We analyze in details the class of frames...

On control problems of minimum time for Lagrangian systems similar to a swing. I. Convexity criteria for sets

Aldo Bressan, Monica Motta (1994)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

One establishes some convexity criteria for sets in R 2 . They will be applied in a further Note to treat the existence of solutions to minimum time problems for certain Lagrangian systems referred to two coordinates, one of which is used as a control. These problems regard the swing or the ski.

On control problems of minimum time for Lagrangian systems similar to a swing. II Application of convexity criteria to certain minimum time problems

Aldo Bressan, Monica Motta (1994)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

This Note is the Part II of a previous Note with the same title. One refers to holonomic systems Σ = A U with two degrees of freedom, where the part A can schemetize a swing or a pair of skis and U schemetizes whom uses A . The behaviour of U is characterized by a coordinate used as a control. Frictions and air resistance are neglected. One considers on Σ minimum time problems and one is interested in the existence of solutions. To this aim one determines a certain structural condition Γ which implies...

On D’Alembert’s Principle

Larry M. Bates, James M. Nester (2011)

Communications in Mathematics

A formulation of the D’Alembert principle as the orthogonal projection of the acceleration onto an affine plane determined by nonlinear nonholonomic constraints is given. Consequences of this formulation for the equations of motion are discussed in the context of several examples, together with the attendant singular reduction theory.

On measure solutions to the Zero-pressure gas model and their uniqueness

Jiequan Li, Gerald G. Warnecke (2002)

Mathematica Bohemica

The system of zero-pressure gas dynamics conservation laws describes the dynamics of free particles sticking under collision while mass and momentum are conserved. The existence of such solutions was established some time ago. Here we report a uniqueness result that uses the Oleinik entropy condition and a cohesion condition. Both of these conditions are automatically satisfied by solutions obtained in previous existence results. Important tools in the proof of uniqueness are regularizations, generalized...

On submanifolds and quotients of Poisson and Jacobi manifolds

Charles-Michel Marle (2000)

Banach Center Publications

We obtain conditions under which a submanifold of a Poisson manifold has an induced Poisson structure, which encompass both the Poisson submanifolds of A. Weinstein [21] and the Poisson structures on the phase space of a mechanical system with kinematic constraints of Van der Schaft and Maschke [20]. Generalizations of these results for submanifolds of a Jacobi manifold are briefly sketched.

On the alpine ski with dry friction and air resistance. Some optimization problems for it

Aldo Bressan (1999)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

In the present work, divided in three parts, one considers a real skis-skier system, Σ R , descending along a straight-line l with constant dry friction; and one schematizes it by a holonomic system Σ = A U , having any number n 4 of degrees of freedom and subjected to (non-ideal) constraints, partly one-sided. Thus, e.g., jumps and also «steps made with sliding skis» can be schematized by Σ . Among the n Lagrangian coordinates for Σ two are the Cartesian coordinates ξ and η of its center of mass, C , relative...

On the analytic non-integrability of the Rattleback problem

H. R. Dullin, A.V. Tsygvintsev (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

We establish the analytic non-integrability of the nonholonomic ellipsoidal rattleback model for a large class of parameter values. Our approach is based on the study of the monodromy group of the normal variational equations around a particular orbit. The imbedding of the equations of the heavy rigid body into the rattleback model is discussed.

Currently displaying 1 – 20 of 39

Page 1 Next