CS177 Assignment 3 Spring 2003

Consultant's Report on the Feasibility of adding a Moving Sidewalk Between Lot 30 to West Campus Drive.

Due: 11:59pm Friday June 6

I. Summary

Based on your preliminary work in Assignment 2, the campus has decided that the highest priority location for installing a moving sidewalk is to connect the following two locations:
  1. the ``grand pedestrian staircase'' at the entrance to parking lot 30, right next to the existing sidewalk that runs under the 215 freeway along the west side of Canyon Crest Drive, and
  2. the intersection of West Campus Drive and Canyon Crest Drive, beyond which the flow of pedestrian traffic spreads out in multiple directions (i.e., east towards Olmsted Hall, north towards Sproul Hall, or west towards the Barn).
Because of cost and space limitations, the campus can only afford to install one unidirection moving sidewalk in this location. However, it could change directions at different times of day to better fit the current traffic patterns (i.e., north towards campus in the early morning, and south towards parking lot 30 late in the afternoon). Should campus go ahead with this moving sidewalk project? Justify your answer.

NOTE: A sample  CSIM solution to assignment 2 (after all the generalized topology and routing code has been stripped out) is available here. You can use it to run your experiments for assignment 3 if you wish. You still need to create your own input files for this assignment, because setting up the problem and analysing the results represents the main part of this assignment!  However, if you just want to play with the program, I have also provided some stripped down versions of the topology and rate files that I gave you for assignment 2, which describe the single path between Sproul and the Clock Tower.

II. Model Inputs

A significant part of this assignment is to create your own input data for the model and to explain the validity of that data. This will require you to spend some time observing the pedestrian traffic flow in this location at different times of day. However, to limit the amount of time you need to spend on gathering data, you can pool your observations with other students in the class by posting them to the class mailing list.

To run your experiments, you will need to find the following model inputs:
  1. Pedestrian interarrival time distribution. Recall that in Assignment 2 we just defined it to be exponential. This time you need to determine whether this assumption makes sense. Since it would be very tedious to gather enough information about interarrival times to answer this question, I have provided a sample input file here. We will assume that this file represents the output produced by a piece of test equipment we borrowed from the Mechanical Engineering department that records a time stamp (in units of seconds since the start of the test) each time a pedestrian interrupts a laser beam that runs across the sidewalk.
  2. The mean arrival rate for pedestrians walking towards campus and away from campus at different times of day. You will need to measure this data, and share it with your classmates. Clearly, we expect the rate towards campus will have a peak just before the start of each class period (i.e., once per hour on M/W/F or once every 1.5 hours on Tu/Th) while the rate away from campus will have a peak just after the start of each class period. Since the moving sidewalk system must be able to handle the busiest traffic periods, you need to estimate these arrival  rates at different times of day so you can create several test cases, with different ratios between the pedestrian arrival rates going towards campus and away from campus. Note that you do not need to execute a separate simulation experiment for each set of measurement data. Instead, you need to use the data to design a few good test cases.
  3. How many of the pedestrians wishing to cross the street at West Campus Drive at different times of day are delayed by vehicle traffic, and by how much. Similarly, how many vehicles travelling through this intersection are delayed by pedestrians crossing the street, and by how much.
  4. The width of the existing path and moving sidewalk. (Don't forget that the outside of a moving sidwalk, which takes away space from the existing path, is significantly wider than the inside, which can be used by people to walk and/or stand!) You may want to visit a nearby shopping mall to get some information about the dimensions of their escalators.
  5. How quickly people walk, and under what circumstances (if any) do they pass slower people. Are there a significant number of people using the path that don't fit the standard pedestrian profile? (For example, people riding bicycles, scooters or skateboards. What about people in wheelchairs or on crutches?)
To make it easier to gather the necessary data, you must each contributeat least 6 sets of measurement data to the pool, each covering a 5 minute observation period at one end of the existing path, covering items (2) and (4) in the list of model inputs.

III. Recommendations

In your Consultant's Report, you need to present your overall recommendation (i.e., yes or no), along with your estimate for the average reduction in travel times between these two points at different times of day if the project were built. Be sure to provide enough information about how you obtained these results (i.e., confidence intervals for your output statistics, tests of goodness of fit for your input parameters, the schedule for which direction the sidwalk is moving, etc) to convince the Chancellor that you know what you are doing.

In addition to the basic yes/no recommendation, you should also consider the option of extending the campus end of the moving sidewalk an extra 50 feet beyond the intersection to reduce the conflict between pedestrians and vehicles at the corner of West Campus Drive and Canyon Crest Drive. Since this will require the construction of bridge to carry the moving sidewalk above the road, this option would double the cost of the project. Does this option make the project more valuable, or less valuable?