Acceso usuarios
David Cobos Godoy
Hoy en día en la búsqueda de la optimización del tiempo resulta imprescindible en cualquier empresa, administrarlo de forma eficaz permite reducir costes, aumentar la satisfacción de los clientes, mejorar los resultados con menos esfuerzos.... Los diagramas de Gantt son sin duda de gran ayuda en esta labor, existiendo herramientas informáticas que permiten no solo su repre- sentación gráfica de forma muy sencilla, sino la explotación de los datos que se desprenden de la relación existente entre el final e inicio de una actividad, con el final e inicio del resto de actividades. En el presente artículo se propone, en base a la experiencia, una metodología de trabajo para controlar el tiempo de un conjunto de actividades, así como el planteamiento y la solución al problema de la Doble Ligadura, que a buen seguro, habrá dado más de un quebradero de cabeza a muchos técnicos.
Many technicians, in their professional activity, need to control the execution deadline of all the activities or components that make up projects, works, and processes. In an attempt to address that need, and even before the existence of computers, Henry L. Grantt proposed a methodology for the graphic representation of those activities, so as to give an approximate idea of who they each interacted with the others, as well as each of the activities’ impact on the total execution period.
Computer science has allowed the creation of various tools that lead to easily and intuitively elaborate Grantt diagrams, and to use the information about each activity’s duration and the relation that exists between the start and end of each activity with the others.
The Critical Path analysis allows the classification of activities as critical and non-critical. A delay in execution of the former will result in a delay on the total execution period, whereas non-critical activities function within a margin in such a way that a delay in completion will have little to no impact on the total execution period.
Among all of the computing tools in existence on the market for the generation of Grantt diagrams, Microsoft Project is perhaps the most widely used by technicians. It basically requires two inputs: the estimated duration of each of the activities making up a project, and the existing relations between their start and end.
Said relations require conditioning through Restraints, the end or start of an activity with the start or end of another. These restraints imply the joining of two activities under the condition that the start or end of one will only occur after a determined period of time from the start or end of the other. Microsoft Project presents the important restriction of not allowing to establish more than one restraint between two activities; meaning, if for instance, the start of one activities is conditioned by the start of another, there will not be any more relations between those two activities, such as the end of said activities, in which case incorrect or hardly comprehensive data may be constructed.
The above mentioned restriction is not a minor problem, for if analyzed correctly, when the start of one activity conditions the start of another, which frequently occurs, the ends of both activities will likely also be similarly related. For example, a facade closing evidently cannot be started until part of the structure has been completed, but it is not less true that the closing cannot be finished until after the total execution of the structure.
In this article, I will attempt to explain in simple but rigorous manner the fundamental elements of the technical programming of a project. A work methodology will be proposed to ease the work of the technicians, and I will try to offer a solution to the problem of the Double Restraint between activities, which has certainly been making it difficult for the many technicians who use Microsoft Project on a daily basis.
