VCT - Rocketry Construction Toolkit Software

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vcp

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I've mentioned this a few times recently, but although it's something old, I don't believe I've ever really introduced it properly. VCT was something I started almost 20 years ago, but when the VB6 programming tools became obsolete, it languished and was never finished. I always meant to move it to another language, but that never happened. For many years I believed that the VCT program didn't run on later Windows systems. However, it seems that it does run at least on Win7 and Win10 (haven't tried others), and the parts of VCT that were finished are pretty useful. So I'm going to take this thread to introduce the tools of VCT.

The VCT splash screen - I was surprised to see that this dated back to 2001.
vct - splash.JPG

The VCT main screen:
vct - main.JPG
Here you can see the tools that are available and the unfinished grayed-out tools that I had intended to include. Many of the unfinished tools actually had a lot of work done on them, and the code for those tools may still exist in the source, but they were never finished in a ready-to-use state.

The finished tools that are available are:
  • Fin Radial Position - AKA Fin Alignment Guide.
  • Tube Miter Template - template guide to cut a tube at an angle.
  • Tube Coupler - a silly little guide to tell you how much to slice out of a tube to make a coupler to fit inside that tube.
  • Shroud - usual tube-to-tube shroud template generator.
  • Altitude Tracking - remember trackers?
  • Static Port Sizing - calculator for number and size of altimeter port holes.
  • Ejection Charge - ejection charge and seperation velocity calculator.
The installation file for VCT is attached to this post, and each tool will be detailed in the following posts.
 

Attachments

  • vct.zip
    1.7 MB · Views: 102
VCT FIN ALIGNMENT GUIDE / FIN RADIAL POSITION GUIDE

This is actually two tools in one. From one body tube and fin dimension data entry, you can create and print both your typical (end view) Fin Alignment Guide, and a Fin Position Wrapper.
vct - fin align.JPG
vct - fin wrap.JPG

With most of the graphical tools, there is a tab labeled 'Quick Help' that details the required and optional entries. Select the 'Alignment Guide' or 'Position Wrapper' tabs to see a visual of the selected guide. Most of the entries are self-explanatory, but there are a couple of nifty features worth pointing out.

- If you enter an 'Incidence Angle', the Position Wrapper will produce a guide that gives you 'angled' fins that will induce a spin. This entry has no effect on the Alignment Guide.​

- There is a box for '# Fins' under the 'Even Spacing' label. A tic box to the right will let you increment the number of fins up/down, and the box below that will show the number of degrees between fin locations.​

- There is also a 'Variable Spacing' control below the 'Even Spacing' control. With Variable Spacing, you can select a number of fins, up to eight, and enter the specific degree location of each fin. The example view of the tool shows an example of this.​

- Tile prints across pages. In the view tabs for both tools, you can see faint white lines that depict separate pages of the print. If the guide to be printed doesn't fit on one page, the print will 'tile' across multiple pages. The number of pages needed will be added automatically. The pages can then be taped together into a single large page. Since printers typically don't print to the edge of a page, there are offset alignment 'corners' printed on each page. Align those corners, and the overall print will be aligned.​

- Print options: You can print directly to your installed Windows printers, or to a .pdf file if you have a .pdf printer destination installed (like cutePDF or many similar others). You can also print directly to a .dxf file which might be useful for a CNC or laser cutter. If you have a large format printer with a Windows driver, like a pen plotter, it should detect the size and print right to a B, C or D size sheet (I have done this, and it works, but YMMV).​

- Units / Data Entry: inches, feet, millimeters, and centimeters are available independently for each entry. Under the 'Units' menu item, you can change all entries to inches or cm at once. Note that the changing the units operates on the value that is currently entered, so you would usually want to select the units first, then enter the value. The tube size may be entered as the usual diameter, or as a circumference, which might be easier to measure especially on large tubes.​

- Other Gadgets: Most of the graphical tools have some common checkboxes that turn on/off elements of the view. They are grayed out if not appropriate to a particular tool.
  • Alignment Arrows adds some small pointy arrows that might help to align wraps guides, etc.
  • Glue Tabs adds some tabs at the end of wraps for gluing.
  • Centerlines adds centerline marks where appropriate.
  • Tube Ring adds a separate ring that might be helpful to center a tube on a guide.
  • Bold makes the print lines heavier - on some printers they might come out a bit light.

Defects / Incomplete Features

- At the bottom of the guide view panes, you can see some buttons that are chopped off. Sorry, I can't reposition them, but they are just 'Print Setup' and 'Print' buttons, and those functions are available from the 'File' menu. (You probably can still click on the buttons though.)​

- An important feature that I was working on but didn't finish was a selectable body tube database, that would have avoided the need to enter diameters for standard tubes. You can see the 'Selected Tube' area at the top, but alas, unfinished.​

- Ignore the 'Plan View' tab; that is something that was unfinished in all of the tools.​

The installation file for VCT is attached to the first post of this thread.
 
VCT TUBE MITER

This tool is used to create a tube wrapper that will allow you to mark the cut line for a straight angled cut to a body tube.
vct - tube miter.JPG
With most of the graphical tools, there is a tab labeled 'Quick Help' that details the required and optional entries. Select the 'Print Prevue' tab to see a visual of the wrapper. Most of the entries are self-explanatory, but there are a couple of nifty features worth pointing out.

- Tile prints across pages. In the prevue tab, you can see faint white lines that depict separate pages of the print. If the guide to be printed doesn't fit on one page, the print will 'tile' across multiple pages. The number of pages needed will be added automatically. The pages can then be taped together into a single large page. Since printers typically don't print to the edge of a page, there are offset alignment 'corners' printed on each page. Align those corners, and the overall print will be aligned.​

- Print options: You can print directly to your installed Windows printers, or to a .pdf file if you have a .pdf printer destination installed (like cutePDF or many similar others). You can also print directly to a .dxf file which might be useful for a CNC or laser cutter. If you have a large format printer with a Windows driver, like a pen plotter, it should detect the size and print right to a B, C or D size sheet (I have done this, and it works, but YMMV).​

- Units / Data Entry: inches, feet, millimeters, and centimeters are available independently for each entry. Note that the changing the units operates on the value that is currently entered, so you would usually want to select the units first, then enter the value. The tube size may be entered as the usual diameter, or as a circumference, which might be easier to measure especially on large tubes.​

- Other Gadgets: Most of the graphical tools have some common checkboxes that turn on/off elements of the view. They are grayed out if not appropriate to a particular tool.
  • Radial 30 degree Locator Marks - just some added lines that might help with aligning/locating things.
  • Alignment Arrows adds some small pointy arrows that might help to align wraps guides, etc.
  • Glue Tabs adds some tabs at the end of wraps for gluing.
  • Bold makes the print lines heavier - on some printers they might come out a bit light.

Defects / Incomplete Features

- An important feature that I was working on but didn't finish was a selectable body tube database, that would have avoided the need to enter diameters for standard tubes.​

- Ignore the 'Plan View' tab; that is something that was unfinished in all of the tools.​

The installation file for VCT is attached to the first post of this thread.
 
VCT TUBE COUPLER

This is a tool used to create a tube wrapper that will let you mark off the slice of a tube necessary to reduce the diameter to create a coupler that will fit into the original tube. Yeah, it's pretty stupid simple, but it might get you ahead of a cut-n-try method. If you don't want to bother printing a wrapper, it also just tells you the width of the slice to be removed.
vct - coupler.JPG
With most of the graphical tools, there is a tab labeled 'Quick Help' that details the required and optional entries. Select the 'Print Prevue' tab to see a visual of the wrapper. Most of the entries are self-explanatory, but there are a couple of nifty features worth pointing out.

- Tile prints across pages. In the prevue tab, you can see faint white lines that depict separate pages of the print. If the guide to be printed doesn't fit on one page, the print will 'tile' across multiple pages. The number of pages needed will be added automatically. The pages can then be taped together into a single large page. Since printers typically don't print to the edge of a page, there are offset alignment 'corners' printed on each page. Align those corners, and the overall print will be aligned.​

- Print options: You can print directly to your installed Windows printers, or to a .pdf file if you have a .pdf printer destination installed (like cutePDF or many similar others). You can also print directly to a .dxf file which might be useful for a CNC or laser cutter. If you have a large format printer with a Windows driver, like a pen plotter, it should detect the size and print right to a B, C or D size sheet (I have done this, and it works, but YMMV).​

- Units / Data Entry: inches, feet, millimeters, and centimeters are available independently for each entry. Note that the changing the units operates on the value that is currently entered, so you would usually want to select the units first, then enter the value. The tube size may be entered as the usual diameter, or as a circumference, which might be easier to measure especially on large tubes.​

- Other Gadgets: Most of the graphical tools have some common checkboxes that turn on/off elements of the view.
  • Alignment Arrows adds some small pointy arrows that might help to align wraps guides, etc.
  • Glue Tabs adds some tabs at the end of wraps for gluing.
Defects / Incomplete Features

- An important feature that I was working on but didn't finish was a selectable body tube database, that would have avoided the need to enter diameters for standard tubes.​

- Ignore the 'Plan View' tab; that is something that was unfinished in all of the tools.​

The installation file for VCT is attached to the first post of this thread.
 
VCT SHROUD TEMPLATE GENERATOR

This tool is used to create a template for a typical conical paper (or whatever) shroud that connects two tubes of different diameters.
vct - large shroud.JPG
With most of the graphical tools, there is a tab labeled 'Quick Help' that details the required and optional entries. Select the 'Print Prevue' tab to see a visual of the wrapper. Most of the entries are self-explanatory, but there are a couple of nifty features worth pointing out.

- Tile prints across pages. In the prevue tab, you can see faint white lines that depict separate pages of the print. If the guide to be printed doesn't fit on one page, the print will 'tile' across multiple pages. The number of pages needed will be added automatically. The pages can then be taped together into a single large page. Since printers typically don't print to the edge of a page, there are offset alignment 'corners' printed on each page. Align those corners, and the overall print will be aligned.​

- Print options: You can print directly to your installed Windows printers, or to a .pdf file if you have a .pdf printer destination installed (like cutePDF or many similar others). You can also print directly to a .dxf file which might be useful for a CNC or laser cutter. If you have a large format printer with a Windows driver, like a pen plotter, it should detect the size and print right to a B, C or D size sheet (I have done this, and it works, but YMMV).​

- Units / Data Entry: inches, feet, millimeters, and centimeters are available independently for each entry. Note that the changing the units operates on the value that is currently entered, so you would usually want to select the units first, then enter the value. The tube size may be entered as the usual diameter, or as a circumference, which might be easier to measure especially on large tubes.​

- Calculated Shroud Dimensions: If you aren't printing a shroud template, these dimensions can be used to lay out the shroud directly on the material to be cut.​

- Other Gadgets: Most of the graphical tools have some common checkboxes that turn on/off elements of the view. They are grayed out if not appropriate to a particular tool.
  • Radial 30 degree Locator Marks - just some added lines that might help with aligning/locating things.
  • Alignment Arrows adds some small pointy arrows that might help to align wraps guides, etc.
  • Glue Tabs adds some tabs at the end of wraps for gluing.
  • Bold makes the print lines heavier - on some printers they might come out a bit light.

Defects / Incomplete Features

- An important feature that I was working on but didn't finish was a selectable body tube database, that would have avoided the need to enter diameters for standard tubes.​

- Ignore the 'Plan View' tab; that is something that was unfinished in all of the tools.​

- Ignore the 'Cant Angle' box; that was for offset shrouds but never implemented.​


The installation file for VCT is attached to the first post of this thread.
 
VCT ALTITUDE TRACKING

Remember altitude tracking, with trackers? This is a simple implementation of tracker data reduction to determine an altitude, using the Geodesic calculation method. Not much to it.
vct - altitude.JPG

Incomplete Features

- I had been planning to implement multiple stations and a record-keeping system, but that's pretty much history now anyway.
The installation file for VCT is attached to the first post of this thread.
 
VCT EJECTION CHARGE CALCULATOR

This calculator implements the generally accepted equations for determining the needed size of an ejection charge. It goes quite a bit beyond most ordinary calculators, however.
vct - eject calc.JPG
- Volume Calculations: In the usual way, you can just enter the parachute compartment diameter and length to get the volume to be pressurized, but there are additional options...
  • If, in addition to the parachute compartment, there is a 'stuffer tube' (that's a smaller diameter tube used to reduce the volume of the parachute compartment), it's volume may be added to the volume to be pressurized by entering its length and diameter.
  • If you want to consider the shoulder length of the nose cone as reducing the volume of the parachute compartment, you may enter the length of that shoulder here. This entry is required if you want the calculator to produce separation velocity estimates (it's the effective 'barell length').
  • If you want to consider the parachute and recovery components as reducing the volume of the compartment, you can enter a diameter and length estimate of their size to subtract from the compartment volume.

- Component Weights: Entirely unnecessary for an ejection calculator, but if you want it to estimate separation velocity and acceleration, entries are needed for these items.​

- The Calculation Part: Here's where it gets pretty cool. You can enter one value of either...
  • the black powder weight
  • the black powder volume
  • the desired ejection charge pressure
  • the desired nose cone separation force
  • the number of shear pins
  • - or -
  • the desired separation velocity
...and it will calculate all of the other values.​

- Black Powder Volume: Select either FFFFg or FFFg, the volume calculation is slightly different for each.​

- Shear Pins: Of course, this if 'iffy'. You enter a shear pin type (currently limited to #2 or #4 nylon screws). If you are calculating from some other value (e.g., BP weight), the value calculated here is the maximum number of pins that can be sheared by that powder. If you enter a quantity of shear pins and calculate from that quantity, the values for powder are the minimum amount needed to shear that quantity of pins. Note that no margin is calculated here - it's just giving a starting lower value of what's needed. If I recall correctly, there is a text file of shear pin type / shear force that can be edited to add or change shear pin types/values.​

- Separation Velocity: What does the knowledge of the Separation Force or Ejection Pressure buy you? Not much really - what you really want to know is that the components separate 'smartly' i.e., the velocity. Through a lot simplifications and assumptions (plus some hand-waving), this is an estimate of the free-body separation velocity.​

- Caution: Read Me. This is a list of the assumptons, warnings, and stuff you should read. Most calculators make many of these same assumptions.​

- Freedom of Units: As with the other VCT tools, there are multiple units options available independently for each entry. Note that the changing the units operates on the value that is currently entered, so you would usually want to select the units first, then enter the value.
  • Note that black powder weight can be entered in oz., gm, or grains.
  • For pressure, you've got psi, Atm, Pascal, or KPascal.
  • For separation velocit there is fps, mph, m/s, or Kph.
  • For acceleration there is g's, ft/sec2, cm/sec2, or m/sec2.
  • For volume there are cubic inches, cubic feet, cubic centimeters, or cubic meters (for you guys with way too much... space).

The installation file for VCT is attached to the first post of this thread.
 
Last edited:
Thank you Gary for posting this! I found VCT years ago, and it has been very useful to me. I had links to it posted on my website, but they seem to go stale every so often, so I was afraid it was gone for good. This one seems to be sticking so far. But I am glad it has a home on TRF now.
 
I was able to run VCT on Windows 10, which really surprised me. I have an 11x17" printer and years ago printed many fin alignment guides on it that I spay-glued to foam core and cut out. Really made a big difference when I first started in getting good fin alignment. Regarding the ejection calculator, there is a text file that has the following 2 entries:

"#2 Nylon Screw",35
"#4 Nylon Screw",53

I assume the values are pounds of shear force? I really like the fact that I can calculate velocity of nosecone based on its weight. To me, that is an important consideration in a successful deployment. Really glad you brought this up, I had not even thought to try running it on my new laptop.

Thank you!


Tony
 
Regarding the ejection calculator, there is a text file that has the following 2 entries:

"#2 Nylon Screw",35
"#4 Nylon Screw",53

I assume the values are pounds of shear force?

Yes, those are values that someone came up with a long time ago. If there are better values, that text file can be edited. I'm pretty sure that additional pin types can be added as well; the program reads that file when it starts up. For example:

"#2 Nylon Screw",35
"#4 Nylon Screw",53
"#6 Steel Screw",1000

...should work fine.
 
Getting an Error: COMDLG3.OCX is not registered properly or one of it's dependents.... missing or not working properly. Keep getting win 10 warning about unregistered software.
 
Ok, got it to work after a little tinkering under Win 10 Pro.
I run a SSD as my C drive to prevent it from filling up.. I install most programs on the D Drive for data.
Crated a folder for it, no go, had to add; Run under compatibility of Win 7 and Administrator
 
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