Simulation and Optimization of Urban Environments

Simulation of Operational Concepts

Simulation is one tool that can help quantify the benefits of different operational concepts, which in turn can help answer questions about design options. A common engineering practice is to first document and construct a baseline validated simulation of the system you have in place, then extend the simulation with new proposals for changes to equipment or operation. After analysts have evaluated the performance benefits projected by different options, engineers could make a decision, implement the change, and then re-validate the simulation to make sure their model matches the performance of the modified actual system. Unfortunately, few municipalities maintain validated simulated representations of their jurisdictions, much less use them as decision making tools, deferring more towards the use of surveys and standalone analytical teams. Building such a tool would not only give them better access to information about the physical arrangement and performance of their existing town, but could also be used as a ``vision communication tool'' to the populace in order to cut down on some of the arguments and political delays.

Simulation as a Decision Support Tool

Several initiatives are currently underway to rethink the way metropolitan areas are designed. This simulation modeling and analysis framework can provide a design planning and evaluation tool to assess several integrated mass transit paradigms such as busing, rail, and PRT-type (personalized rapid transport) networks to help identify and accelerate acceptance of the worthwhile investments.

The use of simulation as a decision-support tool could provide a measure of accountability that would help avoid or at least temper some of the larger controversies over the past century of rapid technological change. The history of our infrastructure has been peppered with some epic and ultimately costly battles over different modes of transfer, such as the turn of the century Edison - Tesla battle to establish AC or DC as the power delivery standard [27] or the politicized finger pointing over whether GM was duly responsible for taking control of streetcar operations in the 20s in order to dismantle them in favor of GM-manufactured buses [41,14]. Having detailed records of the simulations used to provide hard data on which broad policy decisions are based could help justify your decision later. With more exotic options pushed by several technology firms, we ought to determine the selection of major communications upgrades or transit systems based on available technical data, and not on which company has the best connections to the civil servants responsible for municipal decision making.

Ultimately, if this were to evolve into a fully-featured urban simulation tool, it could be used as a rapid prototyping environment for proposals to system changes big and small. When this functionality matures, a municipality might require a simulation-based analysis to accompany any new infrastructure proposal as part of a gateway approval process. As standard patterns are built up, the simulation framework may morph into a design tool, replete with a library of openly available blueprints, guidelines, and standards (as well as freely customizable sections) to that can be assembled to achieve development goals. Furthermore, as the process becomes automated, it might incorporate more direct civil input, turning review and evaluation of problem areas and proposals into something of an experiment with direct digital democracy governance, in which the citizens can interact as something like a hive mind. Or so goes the vision.

Urban Simulation in the Media

Previous well-known works that tackle the task of urban simulation includes two series of open-ended games from Maxis (now part of Electronic Arts) that approach the problem from different scales: SimCity and The Sims. Certain versions of SimCity (2000 and 3000) even had actual arcology units in them (although since they were entirely self-contained, they really added little to the game play other than to provide an easy way to boost your population tax base). To some extent, these games could be used to experiment with different urban or residence layouts, but they primarily pattern themselves after common current day paradigms and lack the flexibility needed to really turn its simulated environment into useful data. Hopefully these games will serve to influence the next generations of urban planners and administrators, who might come to expect and demand some of the streamlined user interfaces to command, control, and instantaneous reporting of city condition and resources. Beyond that, there is not much published in the way of complete city and/or lifestyle simulation. This might be the case partly because most analysis can simply be done on spreadsheets using historical data tracked by government agencies, and partly because most simulation programmers are still busy developing their craft while simulating more interesting things such as data [31] and transportation networks [33].

Optimization of Mass Transit Operations

The purpose of the optimization tool embedded within the simulation is to provide some measure of intelligence that could demonstrate an advanced, demand-responsive modeling scheme. We'd use this flexibility to investigate the potential effectiveness of various mass transit paradigms, especially with regards to network topologies and their ability to model:

1. The distribution of various loads generated by work nodes and residential nodes.

2. The size and connectivity constraints of various shared vehicle networks shuttling people and goods between nodes.

3. The ability for the passengers and cargo to make transfers between different vehicles as well as modes of transit.

Applying a schedule optimizer ensures that we evaluate different transit paradigms on a level playing field. Different transit schemes utilizing rail, bus, and PRT styles of vehicle sizes and routing will get a fair shake at providing the maximum theoretical performance possible given the same physical construction constraints. Each mode of transit will have some measure of routing intelligence that should reflect the optimization computing power that should become more pervasive in the near future. They would all operate with the benefit of an intelligent central dispatch that characteristic of advanced transportation systems. System operators will have the freedom to direct their fleet about the network and pick up, transfer, and drop off groups of passengers as necessary to meet passenger demand as quickly and efficiently as possible with their existing resources. Mass transit vehicle fleets will only be subject to the physical constraints of vehicle passenger capacity, station berth / terminal / gate capacity, and the existence of connective links between stations.