TY - JOUR A1 - Sarac, Yesim A1 - Zuazua, Enrique T1 - Sidewise control of 1-d waves N2 - We analyze the sidewise controllability for the variable coefficients one-dimensional wave equation. The control is acting on one extreme of the string with the aim that the solution tracks a given path at the otherfree end. This sidewise control problem is also often referred to as nodal profile or tracking control. First, the problem is reformulated as a dual observability property for the corresponding adjoint system. Using sidewiseenergy propagation arguments the sidewise observability is shown to hold, ina sufficiently large time, in the class of BV-coefficients. We also present a number of open problems and perspectives for further research. KW - 1-d wave equations KW - BV-coefficients KW - nodal profile con-trol Y1 - 2021 ER -