Prospective Research Topics


Are people interested in carfree development? Who? Where? What kind? How much money do they make? How many children do they have?


What will it cost? How does that compare with other development/ redevelopment options? Can we quantify significant differences in "operating costs" for residents, businesses, local authorities in carfree areas vs. autocentric ones? Are there important differences in the impact of carfree (vs. autocentric) development on externalities?

Compare all of the economic and social advantages/disadvantages of carfree vs autocentric. Results shound include numbers, not just relative comparisons, and should deal with both public and private costs.


What are the possible approaches to funding projects?


How well does the process of designing and implementing carfree districts mesh with existing planning and zoning models and procedures? In what ways might our projects be problematic or even prohibited under prevailing codes? What needs to change and who needs to be educated/convinced to effect that change?

Design and Planning

How (in detail and with specificity) might the Reference Design be adapted and applied in real-world settings? Pick model sites, create the designs and elaborate plans for development.

Urban Modeling

The purpose of the model that would be developed is to analyze a number of important urban indicators on the basis of the parameters outlined in Carfree Cities (plus others that may be identified). The inputs would allow the comparison of statistics for carfree vs. auto-centric development, as well as other possible arrangements. Ideally, the model is sufficiently sophisticated to permit mixed cases, such as the graduated-density, auto-lite (outer districts only) topology envisioned as a further development of the reference design.

Major Inputs

The following important inputs must be allowed:
  • Density of each district
  • Density gradations within each district
  • Building heights, with graduations within districts
  • FAR or other plot-size-determining density inputs, perhaps including space in the interior courtyards (Maybe FAR is an output, and the factors that determine it are inputs; alternatively, other inputs can be given together with FAR to determine one of the important parameters, say building height)
  • Lateral distance between buildings
  • Transport modal mix
  • Right-of-way dimensions
  • Transport system capacities

Numeric Indices

  • Frequency of days with poor air quality
  • Infant mortality rate
  • Poverty index
  • Unemployment rate
  • Literacy rate
  • Incarceration rate
  • Incidence of mental illness

Attributes of Livable Neighborhoods

Perhaps these attributes can be quantified and scored for the various alternatives. What would the scoring system be?
  • Priority for pedestrians (score down for motorized traffic, with a speed factor included)
  • Buildings no higher than six stories (score down for heights above 3 stories)
  • Buildings oriented towards the street (score down for garage doors facing the street)
  • Active street life created by mixed uses (score down for single-use zoning)
  • Nearby, attractive parks (walking distance in time)
  • Transport within easy walking distance (time, but may be scored in Transport section)

Minimize Daily Transport Distance

These may not need to be scored, as they may turn up in other measures.
  • Compact development, so no part of the city is far away
  • Basic shopping within walking distance
  • Work, school, and health care close to home

Minimize Daily Transport Time

Probably, this measure should be based on the mix of daily trips for various purposes. Total time is the easiest way to score.
  • Short walking distance to transport
  • No wait for service
  • No need to transfer from one vehicle to another
  • Direct routing without intermediate stops
  • High acceleration
  • High speed

Transport Costs

Land Consumed by Transport
Execute a detailed analysis (by mode) of land requirements using the following parameters:
  • Rights-of-way
  • Vehicle parking (with adjustments for value of land occupied, whether central or peripheral)
  • Access facilities (stations, etc.)
System Construction Costs (by mode)
Operating Costs (by mode)
Externalized Costs (by mode):
  • Death & injury to bystanders
  • Intimidation of pedestrians & bicyclists
  • Diminished freedom for children
  • Road maintenance costs in excess of road taxes
  • Reduced availability of public transport
  • Noise & vibration
  • Air pollution & climate change
  • Loss of beauty to visual clutter
  • Deterioration of human-scale public spaces

Other Costs

Building Construction
Street Construction

Major Outputs

The following outputs are desired:
  • Building construction costs
  • Street construction costs
  • Transport system construction costs
  • Transport system operating costs (break out by mode)
  • Energy consumed by transport (break out)
  • Energy consumed to heat and cool buildings
  • Energy produced by solar sources within the city
  • General and topical maps (optional, possibly schematic only) (maps must be in PostScript (EPS) and GIF format)
  • Ideally, permit extrusion to 3-D walk-throughs using texture mapping, etc.

Fractal-Based City Builder

The purpose of this project would be to develop city plans, using a variety of user inputs. The inputs would be processed through a series of algorithms to be defined by the project participants. The general system must be capable of handling added design rules and starting conditions as they arise. The development of this software would provide an excellent vehicle for studying the fractal quality of urban planning.

Are there prospective commercial applications for the software? For instance, computer gaming, where it is often necessary to generate convincing virtual urban spaces without spending a lot of time to create them.

Faculty And Student Involvement

The faculty and students would identify various rules for laying out streets, squares, and block interiors. Each variable would have an input mechanism that permitted a range of inputs and was provided with a randomizer that tended to generate values in a spectrum that the user could define. Once the rules are defined, algorithms would be developed to express these rules, and, where possible, the rules would be expressed as fractals. The algorithms would then form the basis for programming.

When the software was completed, the user would define as many departures from the default values as desired. Clicking on a button would initiate the drawing of a district based on the defined rules and input values selected by the user. The speed of the process would be variable, so that users could follow the development of a district and watch for unexpected or undesired behavior. This could be corrected by correcting the algorithms when necessary or by adjusting the input parameters to block undesired results.


Maps in EPS format (Hollier knows of an EPS-GIF converter).
A statistical summary would be a highly desirable addition.


EPS output can be edited in Adobe Illustrator, and possibly other packages.

It should be possible to freeze various aspects of a run and to back up to a branch point and try again. Much of the input will be ranges, with actual values to be determined by a random number generator. It should be possible to select and keep more successful runs and to try again with those that did not work out well. Individual overrides should be possible at almost any point.

New City And District Topoloigies

The Reference Design as defined in Carfree Cities is a useful starting point but only covers a narrow range of conditions and almost entirely dedicated to the "pure" carfree case. A number of other cases certainly exist, including those in which cars are allowed into less dense areas somewhat removed from the dense downtown carfree areas. These compromise scenarios are probably going to be needed during the implementation of downtown carfree districts in existing cities. The spaces should be arranged so that they can later be converted to carfree areas without undue difficulty and expense.

The development of these modified cases could be an excellent context in which students could consider the methods of urban planning and the constraints that each approach to providing transportation imposes on the affected areas.

Hold design seminars/charettes to develop these alternative scenarios.

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