Visualization, simulation and qualitative parameters in urban planning

Many new technologies are being used nowadays in urban planning, such as virtual and augmented reality, different forms of data visualization and sophisticated simulation environments. While all of them are great tools for creating, visualizing and evaluating possible scenarios in terms of quantitative parameters, some issues involve qualitative or subjective parameters, in which case the results of a computer simulation might even lead to wrong decisions.

Let’s take, for example, the case of automotive traffic. A micro-simulation software using a model such as the Travel Demand Model System may show that an increase in the number of road lanes will lead to better circulation. Although some authors are skeptical about the concept of induced traffic demand, in certain situations (e.g. when there are no tolls nor public transportation alternatives) it is possible that new traffic is created after the introduction of new lanes in an avenue or road. The concept of induced demand is very difficult to model mathematically because it involves too many variables, some of which are generally unknown.

In the case of pedestrian circulation, it would be even harder to simulate the increase in trips just because a sidewalk has become wider or more shaded in the Summer, or even more beautiful. In this case, however, technology could be in our favor: a Virtual or Augmented Reality system could be used to validate pedestrians’ intentions to use a walkway for longer walks after they experience it virtually. Of course, some of its amenities, such as the air temperature or the smell of flowers cannot be included in such representation. Still, although there is no guarantee that the design will be successful in convincing people to walk rather than drive, a representation in 3 dimensions plus displacement along an axis, projected on top of the existing environment (in the case of AR) is probably a good test.

In summary, instead of being used just as a tool for “selling” urban planning ideas, VR or AR could be used to test intended or even side-effects that are too subjective to be modeled precisely in an urban simulation environment, and the combination of these two tools could make the assessment of possible scenarios even more accurate.