Miscellaneous Speed from RPM


Overview: Computes the Speed of a vehicle or bicycle based on engine speed and two gear ratios.


Entry into Module:


This module of the program is normally entered by clicking on the REC-TEC block in the upper left of the REC-TEC Window causing the drop-down menu to appear. Place the cursor on the Time - Distance block and click on Acceleration Deceleration Factor on the sub-menu to initiate this module.


Under certain circumstances, the user may choose to use the Files block instead of the drop-down menu approach. Selecting any file with an .RPM extension in the Dialog box accessed from either the Open Single File or Open Multiple Files block opens this module.


Selecting AutoLoad [ON] from either the Setup Menu or the AutoLoad Icon on the upper right side (third line) of the REC-TEC Window automatically loads the scenario that was on the screen when the module was closed, either individually, or when the program was closed. With AutoLoad [OFF] on the main REC-TEC Window, modules will start without loading a file.


Data Entry:


This module contains four data entry blocks within the leftmost frame:

             Engine RPM RPM of the Engine

             Tran Gr Ratio (?:1) Transmission Gear Ratio (N:1)

             Diff Gr Ratio (?:1) Differential Gear Ratio (N:1)

             Tire Radius Center of Hub to Road Surface


Optional Inputs


             Tire Radius Tire Width, Profile, and Rim Diameter (255/60R15) used to compute Sidewall height and Radius.


             Target Speed Target speed used to compute the required RPM based on available input information


Note Module will show formula for speed or RPM as appropriate using Formulae* button


Entry of specific (known) data in the data boxes sufficient to generate an answer causes output information to appear in the Output frame. As the input data is changed, the output data is automatically updated without the need to tell the program to update the output.




The output from this module consists of the repeated Input variables and the computed Speed in both the primary and secondary output configurations as selected in the Setup > REC-TEC menu.




Several Command Buttons appear in a frame located at the lower right corner of the module Window. The Command Buttons allow the user to engage options including the option to Open and Save the data required to generate the scenario shown on the screen at the time the file was saved.


             Open .RPM File Calls up a Dialog box, which Opens any pre-existing .RPM file and displays the output results.


             Save .RPM File Calls up a Dialog box, which Saves data on the screen to files with any user-selectable filenames. This is independent of the automatic saving as LastFile.RPM of the data at the close of this module or the close of the program.


             Formulae Opens a word processor (set by the user in Setup) with a file showing the basic formulae used in this module of the program. While the user may add to or modify the information in this file, it does not change the formulae imbedded into the program.


             Formulae* - Toggles a frame displaying the formulae for computing the unknowns in this module. In addition to the basic formulae, the frame shows intermediate steps with the actual input data shown in the computation.


             N This button toggles a graphical number pad on the screen that can be used to enter data into the input boxes without using your keyboard number pad. This may be useful for presentations as data entry can be accomplished using a wired/wireless mouse.

             Tables / FDA Calls up a frame that permits the user to input the minimum and maximum values for selected input variables along with the interval for Iteration. If Finite Difference Analysis (FDA) is selected, the resulting analysis computes the uncertainty level for the specified range of the input variables.


For a more in-depth description of Finite Difference Analysis, see the Finite Difference Analysis Section of this Manual Press [F2] from any Active module of the program.