TURNING MOVEMENT CALCULATOR VERSION 3.0

Transcription

1 TURNING MOVEMENT CALCULATOR VERSION 3.0 User Guide February 23, 2008 Whitehouse Group Inc. For support: +1 (202)

2 TABLE OF CONTENTS INTRODUCTION... 1 Features... 1 Benefits... 1 System Requirements... 1 GENERAL RULES... 2 USER INTERFACE... 3 STARTING AN ANALYSIS... 5 Step 1 Start TMC Program... 5 Step 2 Click Reset Button... 6 Step 3 Define Intersection Configuration... 7 Step 4 Input Traffic Data... 8 FORECASTING TURNING MOVEMENTS... 9 Step 1 Intersection Leg(s) Constant Option... 9 Step 2 Calculate Intersection Turning Movements Step 3 Display and Save Results SAVING OR OPENING A RESULTS DATABASE EXPORTING RESULTS PRINTING RESULTS SUPPORT/SUGGESTIONS Turning Movement Calculator Page i

3 INTRODUCTION Turning Movement Calculator (TMC) is a tool designed to help transportation professionals forecast intersection turning movements for up to four unique time periods using a combination of available (and often limited) traffic counts, roadway forecasts and/or intersection turn percentages. TMC uses an Iterative Proportional Fitting (IPF) technique that accepts reasonable input values to forecast the most likely turning movements, which may be saved and stored for later retrieval and exported into a comma-separated values (CSV) format for additional analysis and reporting using other popular systems (e.g., Highway Capacity Software (HCS), Microsoft Excel, Microsoft Access, SPSS, SAS, etc.). Features Uses Iterative Proportional Fitting (IPF) technique to calculate expected values Stores intersection data for four time periods in a single database (3 or 4 legs per intersection) Accepts input (seed) turning movements values as absolute values, relative values or percentages Allows specific turning movements to be fixed while solving non-fixed traffic volumes Completes calculations in seconds Controls all outputs to match traffic entering each intersection leg Saves or modifies all outputs for use as inputs in additional calculations Exports to commaseparated values (CSV) format Benefits Increases productivity, reduces project costs and eliminates calculation errors Provides a consistent process that can be used to support single- or multi-corridor traffic studies or small to large-scale traffic impact analyses Supplies transparent, defendable traffic smoothing calculations and results Allows additional analysis and reporting using other popular systems (e.g., Highway Capacity Software (HCS), Microsoft Excel, Microsoft Access, SPSS, SAS, etc.) System Requirements Windows XP or Vista (minimum resolution 1024x768) Turning Movement Calculator Page 1

4 GENERAL RULES The TMC program stores up to 100 intersections for four time periods in a single database. If more than 100 intersections need to be analyzed, save separate database files in up to 100 intersection groups. Define intersection configuration for all time periods within AM Input tab. Intersection can have either 3 or 4 legs. Non-applicable legs may be disabled (hidden) by clicking on the little blue intersection line. To re-enable the leg, click on it again. Input calculation values (numbers and percentages) as integers. All zero input values are output as a zero. If a non-zero output is desired, then a non-zero must be input for that movement. Input data may be entered by tabbing to each individual data-entry box; therefore, once it has been done a few times, data may be entered without looking up at the computer screen. Generally, tab stops occur in the following order: o Intersection Leg Name (description) o Entering west leg- name/volume/left/through/right north leg- name/volume/left/through/right east leg- name/volume/left/through/right south leg - name/volume/left/through/right o Exiting west leg volume north leg volume east leg volume south leg volume Traffic entering and exiting an intersection should sum to the same value before calculations are executed. If this is not the case, the TMC sums all of the traffic entering and (separately) exiting each intersection and then factors all intersection legs equally by the ratio of entering and existing traffic such that total traffic exiting will be set equal to the traffic entering, which is assumed to be constant. A check box on each individual turning movement allows each movement to be held constant. If a check box is enabled, the values for that turning movement must be input as the absolute number of vehicles. Once an intersection has been calculated, the Results tab will be activated and displayed. After calculating an intersection, the Save button (displayed in red) MUST be pressed before moving onto the next intersection. Results are always output as integers. Results MUST be saved within the output file. Output values (results) may always be changed (a particular turn or departure value) and recalculated to see its impact. (This should be an iterative process.) Once satisfied with the results, click the Save button (located under Intersection ) before moving onto the next intersection. Results should always be checked to make sure they make sense, as the old adage garbage in, garbage out still applies. Help is provided for any given item by clicking on that item and hitting F1 on the keyboard. Turning Movement Calculator Page 2

5 USER INTERFACE The TMC program operates as a Windows form, meaning most basic actions are managed through buttons, spin controls and data-entry boxes organized by intersection and time period tabs located above the intersection configuration screen The Windows form usage guidelines are as follows: Intersection Actions 1. Intersection spin control use arrows to scroll up or down the database by individual intersection number (1 through 100). 2. Reset/Start button use this button activate a blank intersection configuration template or to reset the data in an intersection. (Define intersection configuration for all time periods within AM Input tab.) 3. Save button use this button to save raw (unprocessed/uncalculated) data or output results for a particular intersection. The button will have red text whenever it is mandatory to move on to another intersection. 4. Calculate button use this button to calculate turning movement forecasts. The button can be used more than once as results are calculated and adjustments, if required, made. Once satisfied with the results, be sure to hit the Save button for that intersection. File Actions 5. Open use this button to open a previously saved database file. 6. Save use this button to save results or input (unprocessed) intersection data into a database. This button must be used to save results any time a calculation has been made on any intersection. 7. Export button use this button to export results to a CSV file for subsequent processing. Turning Movement Calculator Page 3

6 User Interface Other Actions 8. Print button use this button to print the intersection screen (one screen per print). 9. About button use this button to gain additional information about the TMC program. 10. Iterations use this data box to change the number of calculation iterations performed by the TMC program. The default value is 500 and has been found to be sufficient for all data tested to date. Turning Movement Calculator Page 4

7 STARTING AN ANALYSIS Prior to starting an analysis, it is suggested that all relevant data available (e.g., roadway names, intersection entering and exiting volumes) should be gathered for each time period analyzed, as well as expected turning movement values (absolute values, relative values or percentage as integer). If a leg of an existing intersection does not currently exist, but will in the future, it is suggested that an estimated reasonable starting value be used to produce the first iteration of forecasting an intersection s turning movements. Step 1 Start TMC Program After the TMC program has been started, a screen similar to the one below will appear. Turning Movement Calculator Page 5

8 Starting an Analysis Step 2 Click Reset Button Click Reset button (red arrow) to establish an intersection configuration template (within the AM Input tab display) that can be used to set intersection configuration for all time periods. A secondary prompt screen (red circle) will appear to provide an option to clear the intersection data (reset and open a new intersection configuration template) or cancel the action. Use the Reset Intersection Data button to display a new (blank) intersection configuration template; the TMC program automatically begins with an intersection number of 1 by default. (The intersection configuration for all time periods is defined within the AM Input tab, even if the AM period will not be analyzed. In such cases, only the intersection configuration, intersection name and leg names are required. These parameters will be transferred to all time periods, analyzed or not.) Use the Cancel button if the intersection contains data that needs to be saved or used. Turning Movement Calculator Page 6

9 Starting an Analysis Step 3 Define Intersection Configuration If a particular intersection leg does not exist, click on the black line for that leg (red arrow in the left hand-side figure) and the relevant turning arrows and data-entry boxes will be disabled (hidden), leaving behind only a little blue line. To re-enable the intersection leg, click on the little blue line (red circle in the right hand-side figure). Turning Movement Calculator Page 7

10 Starting an Analysis Step 4 Input Traffic Data Input descriptive and quantitative data by tabbing to each individual data-entry box. (Once it has been done a few times, data may be entered without looking up at the computer screen.) Use the (Intersection) Save button (red circle in the left hand-side figure) to save and store individual intersection input data already entered and then use the (File Actions) Save button (red circle in the right hand-side figure) to save the project, up to 100 intersections. Turning Movement Calculator Page 8

11 FORECASTING TURNING MOVEMENTS Once all the data has been entered, the TMC programs allows a intersection leg(s) constant option and provides descriptive summaries of traffic entering and existing an intersection. Traffic entering and exiting an intersection should sum to the same value before calculations are executed. If this is not the case, the TMC sums all of the traffic entering and (separately) exiting each intersection and then factors all intersection legs equally by the ratio of entering and existing traffic such that total traffic exiting will be set equal to the traffic entering, which is assumed to be constant. Step 1 Intersection Leg(s) Constant Option A check box on each individual turning movement (red circle) allows each movement to be held constant. If a check box is enabled, the values for that turning movement must be input as the absolute number of vehicles and the other intersection values will be adjusted to the degree possible to accommodate this rule. Turning Movement Calculator Page 9

12 Forecasting Turning Movements Step 2 Calculate Intersection Turning Movements Use the (Intersection) Calculate button to execute the analysis. A secondary prompt screen (red arrow in the left hand-side figure) will appear providing the total number intersection legs to be analyzed, summarizes of the traffic volumes entering and exiting the intersection and a note regarding whether the entering and exiting an intersection sum to the same value. Click the OK button to continue the analysis. Another secondary prompt screen (red arrow in the right handside figure) will appear providing the total number of intersection legs processed by the TMC program. Click the OK button to continue the analysis. Turning Movement Calculator Page 10

13 Forecasting Turning Movements Step 3 Display and Save Results Use the (Intersection) Save button (red circle) to save and store individual intersection input data already entered. Output values (results) may always be changed (a particular turn or departure value) and recalculated to see its impact. (This should be an iterative process.) Once satisfied with the results, click the (Intersection) Save button before moving onto the next intersection. Turning Movement Calculator Page 11

14 SAVING OR OPENING A RESULTS DATABASE At any time during the analysis the entire project may be saved within a single database for all intersections (up to 100). Use the (File Actions) Save button (red circle) to create a project file. The *.wgt extension will automatically be appended to the file name. Use the (File Actions) Open button (red circle) to open a previously saved project file. Turning Movement Calculator Page 12

15 EXPORTING RESULTS Use the (File Actions) Export button (red circle) to export the project to a comma-separated values (CSV) format for additional analysis and reporting using other popular systems (e.g., Highway Capacity Software (HCS), Microsoft Excel, Microsoft Access, SPSS, SAS, etc.). The.csv extension will automatically be appended to the binary file name and a secondary prompt screen will appear providing the location of the file ( by default, it will be placed in the same directory as the binary file with the same name but with.csv added to the file name). Turning Movement Calculator Page 13

16 Exporting Results Using Windows Explorer, browse for the file and double-click on it to open it in Excel. Results for all intersections are presented by sequential intersection number and leg. Intersection_Number 1 Intersection_Name Handcart Year _North_Leg_AM_Input_Road_Name Prospect 1_North_Leg_AM_Input_Entering_Volume 402 1_North_Leg_AM_Input_Left_Turn_Volume 50 1_North_Leg_AM_Input_Thru_Volume 50 1_North_Leg_AM_Input_Exiting_Volume 436 1_North_Leg_AM_Resulting_Entering_Volume 402 1_North_Leg_AM_Resulting_Left_Turn_Volume 182 1_North_Leg_AM_Resulting_Thru_Volume 220 1_North_Leg_AM_Resulting_Exiting_Volume 435 1_East_Leg_AM_Input_Road_Name Handcart 1_East_Leg_AM_Input_Entering_Volume 439 1_East_Leg_AM_Input_Left_Turn_Volume 90 1_East_Leg_AM_Input_Right_Turn_Volume 10 1_East_Leg_AM_Input_Exiting_Volume 479 1_East_Leg_AM_Resulting_Entering_Volume 439 1_East_Leg_AM_Resulting_Left_Turn_Volume 392 1_East_Leg_AM_Resulting_Right_Turn_Volume 47 1_East_Leg_AM_Resulting_Exiting_Volume 479 1_South_Leg_AM_Input_Road_Name Prospect 1_South_Leg_AM_Input_Entering_Volume 685 1_South_Leg_AM_Input_Thru_Volume 50 1_South_Leg_AM_Input_Right_Turn_Volume 50 1_South_Leg_AM_Input_Exiting_Volume 611 1_South_Leg_AM_Resulting_Entering_Volume 685 1_South_Leg_AM_Resulting_Thru_Volume 388 1_South_Leg_AM_Resulting_Right_Turn_Volume 297 1_South_Leg_AM_Resulting_Exiting_Volume 612 Turning Movement Calculator Page 14

17 PRINTING RESULTS Results can be printed for one intersection at a time using the (Intersection) Print button (red circle). First, scroll to the intersection number of the desired intersection and then click the Print button (red circle). A standard Windows print dialog box will appear; select the appropriate printer and then click the Print button (red arrow). Turning Movement Calculator Page 15

18 SUPPORT/SUGGESTIONS For support or suggestions, please contact us at Turning Movement Calculator Page 16

19 solutions for a dynamic world