DynaRod was developed as a rod design tool which mainly works based on rod deflection and rod action.  Basic idea is to decide a rod taper through designing its deflection and action.

Another consideration in the development project was how to make it  easier for a rod user (fly fisher) and a rod maker to communicate and agree with on a rod requirements to each other.  For instance, both of user and maker could  clarify the requirements on a rod by looking at the screens of DynaRod.  

DynaRod also challenges to the implementation of the definition of rod action by referring to new words, Rod Angle and Tip Top Tangent Angle.  This challenges to the existing definitions for Fast, Medium and Slow rod action. 

Characteristics of DynaRod

Calculating dynamics

DynaRod performs the calculation of a rod deflection dynamically as its name implies.  For a question "Is there a dynamic type calculation for a static rod model, which means that the rod is not moving?", the answer is YES.  To understand this clearly, let's consider a rod which is fixed to the wall at its grip and the rod hangs a certain weight at the tip top.   The rod will start bending from the tip top and balance at a certain level with flexure.  DynaRod performs the calculation of the  bend angles of this rod dynamically.  "To calculate dynamically" means that the shape of the rod  "one second after" is calculated based on the shape of the rod "one second before".  This type of calculations are continued until the rod finally balances.

For a dynamic rod model, the dynamic calculation must assume that the rod is moving.   That is, when a rod moves in a certain duration of time, for a certain distance and towards a certain direction, DynaRod calculates the receiving load on the rod, and calculates the deflection and stress as the result of rod movement,  dynamically from time to time.  At this time, it also calculates the values for "one moment after" based on the "one moment before" situation.

Then how does DynaRod assume and understand the rod movement?  Users of this tool can define or design the movement of a rod by using one of DynaRod features.  It is called as "definition of casting", or "design of casting style".  If a casting style is defined, rod movement can be automatically calculated for direction, time duration, and velocity, as a result, acceleration and so on.

In dynamic calculation, it divides a duration of time (mostly the unit of second) into several continuous subdivided time blocks, called as "phase".  Within one block of time, calculation is made based on the rod details which  was resulted in the previous time block and this is repeated for all the subdivision of time.  So it spends a little time to complete the calculations for one casting style, then the resulted deflections and stress curves become very close to natural and actual rod deflection as if the rod is cast in actual fishing scene.

Table Driven Calculations

DynaRod performs calculation in various aspects based on the table records which are entered by a user.  And the calculation panels also have additional capability of changing the assumption of calculation.

It does not  perform the same calculation always,  but performs the different calculation according to the changed assumptions via tables and via an input panel, as a user  desired.

One typical example of table, user can specify a new bamboo specie which is to be used for a rod.  Once Bamboo Attribute Table is set with new entry of bamboo specie, user can select the specie when entering or modifying rod specification via input panel.  The rod with that specie has different MOE (Modulus of Elasticity) or Weight per cubic inch.  DynaRod will use those specific attributes for the rod through Bamboo Attribute Table when performing calculation.

Even if the original Bamboo for a rod is recorded as Tonkin, user can change the bamboo on calculation panel when one would like to simulate another specie.  

There are several tables such as Bamboo Attributes, Line Weight, Ferrule, Top Guide, Snake and Stripping Guide, Typical Grip and Reel Seat Arrangement, and Reel Weight.  These all are user definable tables.

Though DynaRod is basically designed for designing Fly rod, Lure rod and Boat rod can also be designed by defining necessary guide sets into the following tables.

- Guide Attributes table
- Top Guide Attributes table
- Users Guide Size Default table

Please refer to Table Setting Menu and each Table panel for further details.

Dual unit capability of Metric and Pond/Yard measure

DynaRod maintains data in ounce/inch unit internally.  Most of screens and PF Setting output have a capability to change the unit of data by pressing [toggle Unit] buttons.  As for Graph data, unit is mostly in inch, ounce and yard.  Since most of data are dealt in inch in rod making, user may not feel any inconvenience.

Difference from Garrison style Stress Curve

The stress curve based on Garrison's mathematics has long been the tool for designing a rod for rod makers.  But it is also true that there are following critiques;

DynaRod's stress curve looks natural since it is drawn based on the dynamic type calculation, 

The differences from static stress curve are;

By those effects, stress curve of DynaRod gives up to be the objective of rod design but becomes a practical stress distribution curve under a certain load.  We can identify how stress is distributed over a rod, practically on the dynamic stress curve.

Establishing a new design criteria

Design approach via static stress curve are often used to convert an existing taper rather than designing a completely new rod taper from scratch.  For instance, we often want to convert two pieces rod to three pieces and vice versa, or want to change the taper from for #4 weight line to for #5 weight, etc..  As dynamic calculation changed the positioning of stress curve from a design criteria to stress distribution graph, a new rod design criteria must be considered, especially in the dynamic calculation.

DynaRod established a new design criteria by "rod deflection" and " action genome".   Genome is a pattern how a rod would act in deflection.  It implies that by taking one of the action patterns, we can inherit the similar deflection to a new rod.  Rod action is really like a genome.

Definition of rod deflection and action genome

Rod Deflection is an overall shape of flexure and the depth of bend form.

Action Genome is patterns of rod bending through a rod.  Action genome has a similar tendency to Garrison's original stress curve, and maintain the physical relationship with rod deflection always.  This nature of action genome makes rod deflection to be a practical design criteria. 

The physical relationship between rod deflection and action genome can be seen in the Deflection Designer tool, which is invoked by the function [Design by deflection].  It is an Excel tool and packaged in DynaRod  As it also works standalone, it can be used as a study material of rod deflection and action genome.  I hope that the usage of the tool would extend the understanding what stress curve means since both are very similar.

DynaRod made it possible to design a rod (taper) from scratch, that is, to produce a new rod (taper) which has not existed.  There are various types of rod tapers remained unknown yet.

About the System

DynaRod is developed on the technology of Microsoft Access, Visual Basic for Application (VBA) and Excel.  Database of Access, processing by VBA and graphic capability of Excel are functionally integrated.  Users can use its functions by communicating with DynaRod via Access screens.

Output of a rod from DynaRod is written into several excel files, one excel file per a function button.  Even after closing DynaRod, user can look into the output excel files standalone.   DynaRod did not develop its own print functions since Excel has flexible capabilities to produce print out hard copies and to make further calculations via its macro.  

Components of DynaRod Package

Download package of DynaRod contains the following components;  
Do not erase any of components from the folder.  All the components should reside in the same folder.

Directory System

Please make sure that your DynaRod directory looks like below;  It is assumed that you put DynaRod home directory under \My Document folder.

\My Document
    |
    |
    +- \DynaRodvnn       (Home Directory)
        |
        +- \data                         (Data Folder for excel output, auto created)
       |
        +- \DBbackup                 (for Export and Import, auto created)
       |
        +- \helpE                        (User guide, pre-defined)
       |
        +- \tap                         (CNC Beveler control file, auto created)