Props Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)

[Redshirt]

I'm now engaged in an epic struggle to cut, file, bend, fold the front row of needles so they can retract fully. All the rest of the rows are simple to retract in comparison. Only the front row has to fold up to get into the nose section. That, my friends, is no small ask. Right now, I'm within about a half inch of getting that front row fully retracted. I have a plan. I just need to get back into the shop.

Hopefully the next update will end in four rows of retractable needles.


Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

Well I'm close to the goal named in the last update. I have the whole retraction system test fitted! Ideally this needs fitted with the top shroud in place. I found this nearly impossible with so small of an access point. What I ended up doing was to apply hot glue to the top of each retractor and fit it in by sticking it to the top shroud. This is not how they will go in the final build as they will instead be bolted to the lower sections. After getting all four retractors fitted I lifted off the shroud/retractor combo and used more glue to attach the retractors to each other to lock down their placement relative to each other.

Of course I needed the needle rows in place to see how they looked and if there was enough room between retractors for them to move. They stick out much further than they did on the original prop so that helps with the goal of making this look more aggressive too!

My next move was to put the shroud/retractor combo back in place onto the chassis/space frame combo and break out the glue gun again to tack the retractor formation to the chassis in the few spots I could reach. You can see in this photo that the chassis (black floor area) has lots of elevation changes and features that make correct placement of each retractor both difficult and critical. But I'm the genius that designed the system so I'd better be happy to live with it.

Now I broke out the heat gun and roasted the surface of the shroud to break the retractors free, leaving them precisely placed on the chassis.

I took the opportunity to fit up the ancillary components as well. That includes the cable runs and and four stepper motors. I'm using a synchromesh cable to drive the needle rows up and down. In some of the photos you can see the shuttle inside each retractor that the needle will mount to. The shuttles will hold the two ends of the synchromesh cable. The cable runs both directions through the retractor, through the cable runs and around a cogged pulley on the stepper motor. This system will allow precise and rapid positioning of the needles with each shot. I chose the smallest stepper motors that I thought were powerful enough for the job. In this case, I used NEMA 17 Short motors. Even though they are much smaller than standard NEMA 17s, they still weigh a bunch and take up lots of space.

So I think my system is going to work. My only real problem is still the front row. That row has to fold or hinge to fit through the throat between the front of the shroud and the nose of the gun. You can see how tight this space is.

I think this will require a redesign for the needle carrier, some aggressive Dremelling of the passage, and possibly some changes to the retractor.


Until next time.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

I led with this one because it is a cool image of the big project coming together.

I'm posting in my own thread and having to acknowledge that it's been over four months since I posted an update so I can make the post. Even the bot is telling me I'm slow.

First up, the side lights are in! Remember, this is going to be a Halo 2 Anniversary Campaign variant of the Needler. Only this Needler and the Needler in Fireteam Raven have the pink lights on the side. The Alpha to Zeta team did a beautiful job on these prints in clear pink.

All the holes are for LEDs to be fitted.

There will be a lot of illumination for these side lights. All the LED mounting holes are placed to fire the light into the part in a way that you won't be able to see the source of the light from and angle outside of the prop. All the areas that won't be see will be painted white to reflect the light back to the emitter areas, then painted black to prevent light leakage into the interior of the prop.

These pictures show where all the lights will go. Between all these lights and the glowing/pulsing needles, this prop will be hard to miss.

The last picture above illustrates a problem that surfaced when I build the spaceframe by fiberglassing all the central parts together. When everything is properly aligned, the upper shroud no longer fits well. I had to cut off the front and align it to the body. This left almost a quarter inch gap!

I needed to fill the space, but also needed it to be strong, especially in the thin areas between the needle holes. I twisted together braids of stainless steel wire, heated them red hot and melted them across the gaps from the top. Then I fiberglassed the gaps from top and bottom. After sanding these patches back, I bondoed any remaining imperfections.

This photo also shows the fitting of the 'stinger' above and behind the grip which will be the magazine for the airsoft functions as well as the airsoft cylinder, chamber and barrel in place to fit within the very tiny confines of the central section.

Unfortunately, this is where rapid progress came to an end and the hard slog of trial and error on needle retraction. To start with, there is no room for several rows to retract inside without clipping--and here you thought that was just an armor problem! There are three problems in this picture. The needles you see are Row 2. They hit the body on the outside near the limit of retraction. The needle assembly is too thick vertically and collides with the needle carrier for Row 1, the grey curved piece above. In this picture I've shaved a tiny piece off the needle to let it fit. Finally, looking above the Row 1 needle carrier for Row 1, you see there just is not much room to drag the Row 1 needles down through that throat. Solving the Row 1 problem has taken more than the time spent on the other rows combined.

So I also was not happy with how the needles stick out of the top all parallel. This is not how the game model looks. They should fan outward for a more aggressive look.

Here is another look at the parallel needles. Looking good, but not great.

So I cut and rewelded the needle bases to get the look I wanted. They look awesome but, as expected, won't retract through the holes in the shroud without breaking. I am now in the process of designing all four needle bases from scratch with spring hinges to get the look and action that I want--more delays . . . .

Meanwhile, over on the electronics and computing side, progress moves slowly because there is so much interaction between all the parts. Below is a screenshot of the serial monitor from a test run last month. Here is some of the logic behind what is happening in the screenshot: The extension state of the needles has to match the number of airsoft BBs left in the magazine. Is the trigger still pulled after the last shot? Do we still have ammo? If so, shoot again. Retract the rear row of needles by one increment. Did the needle row hit the limit switch prematurely? If so, throw an error code and shut down that motor. It goes on . . . . But you see the point, there are a lot of moving parts and a lot of checks and safety measures to keep the mechanism from damaging itself.

Even unfinished, the Needler is already making the CON circuit. I'll wrap up with this picture of it at Phoenix Fan Fusion. Check out the sexy stepper motors in the back! This prop is not light.

That's it for this update. I'm focusing on the new needle base designs. If I can get the physical problems of fitting the needles into the body resolved, I'll return to building the software.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

So many of the problems identified in the last massive update have driven a HUGE churn of re-modelling and revisions of the prototype parts. Results in the physical world have been small, but now the new parts are arriving and I hope to see real advancement in the animation associated both with the needle retraction and the airsoft system. Perhaps the most satisfying new progress is the part that isn't a rework at all (go figure), but just a new surface for part of the exterior to take the prop up a level.

Let's take a look at the grip area. Previously, I've made massive changes to the shape of the pistol grip and trigger to get it to match the game model.

Here is how it started. How it should be. How it ended up.

Not only did I change the overall profile, I changed the border around the hex pattern. You can see that the hex pattern is still wrong. Well, the fix is in. I wanted a rubber grip as well as the right pattern to fix the lack of realism. The solution took several tries of modelling the hex and figuring out differential colors. I chose to use flex filament and 3D printing. Flex filament does not like paint, it just flakes away. The answer was to print sheets of the hex in black and grey. I think you'll agree, the result is a winner.

I'll trim them to fit at the very end of the finish work, but I expect they will look amazing.

The rework part of the project focused on three areas, the needle holders (the parts that slide up and down), the needle carriers (the rail system for the needle holders), and the airsoft bits.

The needle holders need to splay the needles out aggressively when extended and fold up tightly. when retracted. They also needed to hold two LEDs for each needle so I can pulse the pink and purple colors for a 'breathing' effect. While the central needle(s) of each row mount to the holder, the distal needles needed to be spring loaded to splay and fold as needed. That meant incorporating set screws into each piece. I chose to do resin prints for these pieces, but resin is brittle and would not accommodate set screws. So I added provisions to melt in threaded metal inserts to relieve the stress.

The picture doesn't do them justice, but they should work brilliantly. Also in this picture are the HPA (high pressure air) airsoft components. These are resin printed for precision and because I will incorporate a flash charger for pink glow BBs.

The main chassis for the needle retraction system as well as the needle carriers were redesigned from the alterations made to the prototypes and also incorporated plans for using threaded metallic inserts to be more precise and strong.

Redshirt

Overall, the collection of new parts is pretty extensive. Hidden among the discussed parts are also parts for my 717th Xeno-Materials Exploitation Battalion patch and the glitter dispenser that will incorporate with the airsoft system to provide a muzzle flash of needle shards when firing. I plan to make provisions for this system to function even when the airsoft system is disabled for CONs as I think it will really add to the prop effects.

Hopefully the next update shows these parts coming together.

Redshirt

Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

OK, update time. Today I need to talk about the airsoft features while being mindful that this is not a subject I will dwell on here on our 405th forums. The ultimate goal is to produce a dual-use prop that (decommissioned of airsoft gear) can accurately capture the look, sound and animation of the game Needler at a CON, and (when configured for airsoft) accurately and safely capture the in game weapon behavior of the Needler using airsoft BBs in lieu of Subanese crystal shards.

So what do I want it to safely do on the airsoft field?

I want it to fire 30 BBs at a rate of 7 BBs/second, just like in Halo 2 Anniversary.

I want my pink BBs to glow, just like the shards in the game.

I want a brilliant pink muzzle flash with each shot, just like in H2A.

I want my BBs to track moving targets, just like in every Halo game ever.

Wait!? What was that last one? We will get to that. Here is how I'm going to solve those airsoft animation conundrums, AND, much of it is relevant to this project's creds as a CON prop. First safety: This airsoft gun will use an unaltered, universally-approved, off-the-shelf air regulation system to to deliver regulated air to the firing system. What does that get me? Consistent speed of BB's leaving the replica such that when the speed is tested to meet national or field limits, it will stay within those limits at all times.

A 12V solenoid valve will be controlled by the Arduino to pulse air to the custom HPA (high pressure air) system that fires the BBs. This same valve will draw off a tiny portion of air for the muzzle flash system. The muzzle flash system will be available in CON configuration, even when other airsoft gear is removed. The Arduino will set the air pulse frequency and duration, and cut out when the magazine is empty. This will get me my 30 rounds at 7 BB/second.

My magazine will feed the BBs to the firing chamber by way of a feed tube. Just as the BBs enter the chamber, a set of powerful near-UV LEDs will charge the pink glow BBs to maximum intensity to leave the barrel.

Remember the dream of a shimmering charged muzzle flash just like in the game? the tiny air line drawn off of the main air feed will pass into a glitter-filled chamber where it will mix the glitter and air before exiting via a pair of siphon tubes that open up just on either side of the barrel end. This will produce a tiny cloud in front of the gun at each shot. Purple lasers set to an eye-safe dispersal pattern will strobe the glitter cloud for the flash effect. Like I said, this feature will still be available to use even when the prop is demilled to CON-safe configuration. Kinda cool, I think--until the wife becomes irate over the glitter contamination.

Finally, we come to the tracking shards (er, BBs). First, some physics for non-airsofters. Airsoft BBs are slow--relative to metal BBs and bullets. That means that they should quickly drop due to gravity upon leaving the barrel. Instead airsoft BBs are launched with a back spin that uses the Bernoulli principal to gain lift. So, airsoft BBs fly a flat trajectory for a good distance, even as they bleed speed. The system that produces back spin is called the hop-up system. The induced spin is perpendicular to vertical when the gun is held upright and so this lift is against gravity. If you fire an airsoft gun 'gangsta-style' the BB will whip sideways toward whatever direction the gun is tilted. Why? because the lift induced is no longer perpendicular to gravity.

My design will track targets via radar and internally tilt the hop-up system in the direction of target movement, thus causing the BB's flight to curve in the direction of target movement. In other words, my BBs will track just as in-game needles do. Today I will show you the mechanical system. Later, we will build and test the electronics.

So here is the system, minus the commercial tank and regulator system, though they were mounted inside the lower housing at the time of this picture. This photo shows the approximate placement of these components relative to the body shell.

Here is the system by itself. the Arduino-controlled air valve is in the lower right. The blue fitting on the valve is where a tube will run up to the BB firing mechanism at the top right. The stepper motor to rotate the hop-up, based upon the radar signal, is in the lower left. The snake-like tube coming from the right and entering the top is the BB feed tube.

This photo is of the custom BB chamber. It is based on those common to all P90-style airsoft guns. First I modeled the original, then I added provisions for the feel tube and for the LEDs to charge to glow BBs just as they are fired. Initial test fit looks perfect.

Muzzle flash? Here is the glitter chamber. Four bolts, not shown, will hold it together. The entry point for air is that raised hole on the bottom. Exit will be top left in the picture. The exit siphon tube will split into two and pass through those two holes on the frame at the extreme left of the photo. The siphon tubes will emit tiny glitter clouds to either side of the barrel. Again, this feature will remain even when my Needler is configured for prop-only duty.

This view shows the stepper motor and pulleys for rotating the whole firing mechanism to get the BBs to curve either left or right so that they can track a moving target. If my radar system works as expected, I'm almost obligated to follow up this project with a Portal turret build.

One final shot of the whole system. The structure at the top back is the air plenum where air for the firing system enters. It is fixed while everything ahead of it rotates for the tracking system.

The radar system will use a left and right pair of tranceivers (transmitter and receiver built into one unit, about an inch (2.5 cm) across). By comparing any change in the ratio of left and right signal strength, the computer can steer the BBs toward the moved target. This system can be applicable to much more than airsoft. It could be used in many animated props to get them to 'react' to movement. My ongoing build of Timmy the Infection Form comes to mind. Perhaps this system will better enable him to chase children at CONs.

That is it for this update. After this, we will shy away from the airsoft features, but I needed to cover some of the components that will be in the final build and support the overall animation features of the prop. The second-generation of the needle-retraction system is being assembled right now and is leaps and bounds ahead of the first system. I think 80% of this one will make it to the final build. I'm really excited to demo it in a coming update.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Wayward Flood]

I was wondering if you would have an adjustable hop up for tracking. Using radar though?? That's insane man!

 

[Redshirt]

I was wondering if you would have an adjustable hop up for tracking. Using radar though?? That's insane man!

Thank you! That's a good read, there are two ways to go about 'steering the BBs, a hop up that can vary pressure to the left or right side or rotating the whole thing. Since the first solution would require adjustments in tens of thousandths of an inch rapidly and consistently, I went with a brute force approach of just rotating the whole thing (barrel, chamber, cylinder). Once I'm through the testing, I may have it induce a rotation between shots when nothing is tracking to simulate the spray and pray nature of the Needler, though the very short barrel may give that result anyway.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Wayward Flood]

I think you may be fine with replicating the inaccuracy if any of the small electric airsoft guns I used to have are any indication. Especially if you keep the FPS down to simulate the needlers range.

 

[Redshirt]

I think you may be fine with replicating the inaccuracy if any of the small electric airsoft guns I used to have are any indication. Especially if you keep the FPS down to simulate the needlers range.

You are right there. I will be keeping the FPS down to allow the back spin to be greater and thus have a greater steering effect. Besides, I want to give targets enough time to react, but not enough to get out of the way, LoL.

 

[Tyvern]

This is really awesome!

 

[Redshirt]

This is really awesome!

Thank you! The animation goals for this project are crazy, but I've finally reached the point where I feel I'm going to hit the bars. The radar tuning and algorithm will still be tricky and the front row of needles really has to fold tightly to fully retract, but I honestly feel that these things are finally within reach.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

Update time again and this time it is animation progress. So two updates ago I received a ton of resin and plastic printed parts for the needle retraction animation system. This is at least version 4. I'd like to say that I nailed it and everything fit perfectly. I didn't, but I came close enough that with a filing here, a Dremel there and heat application there, I finally have an animation system that I believe will work. Let's take a look:

So here I have assembled the whole retraction system and after a lot of adjusting, there is approximately correct spacing between the rails for the needles to retract. Or is there?

Nope. Close though.

Close enough to convince me we can get there from here. More adjustments needed. But check out the front row. That damn thing is my nemesis. There is so little room for this row to retract into the nose that the two outboard needles have to fold under the center needles to clear the choke point just ahead of the purple shroud. Version 4 works!

So a little digression here as we look at the needle mounts. These are resin prints designed to hold the original needles. Each mount has two holes for a pair of pink and purple LEDs, the outboard needles in every row are on coil springs (same coil used for the BB feed tube). The spring mounts allow the needles to enter the body compactly, but spread wide like open fingers when extended. This gives a much more aggressive look than the NECA prop.

With the shroud fitted on you can really see the fan pattern and meaner look the spring mounts give compared to the NECA.

From straight on:

In short order we were able to get full retraction of all rows. Here is a closer look at how the needles in the front row have to fold to retract fully.

I'll wrap up with a comparison of the NECA with the my results from my new modelling. Not only do the needles fully retract, they extend much further. I think the back two rows need to tilt aft a bit more, but I have that adjustment available to me in the design.

That's all for this update. I'll make a few minor adjustments take the next big steps:
Running the flexible retraction cables
Wiring in the limit switches (lets the computer know when each row is fully retracted)
hooking up electrical to the stepper motors

Hopefully in short order we'll be developing and testing the control software.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

Finally got back at it today 'tuning' the rows of needles. I didn't get very far, just the back two rows sorted out to what I consider their 'final' adjustment for extension, retraction, rake, and spread. Remember from the last update that the back two rows stuck up too straight and three of the rows wouldn't retract fully inside the Needler body. Fixing all that was today's mission (also looks like the mission for tomorrow and the next day . . . .).

I started with the back row. The needle guide was tilted too far back for where the openings are. This caused the needles to stick up too vertically and caused binding of the retraction system:

Comparing what I started with to what I finished with by adjusting the needle guide up at the back actually caused the needle row to lay flatter and thus more correct to the game model:
Before: After:

Those same adjustments also gave a needle spread that looks nice and aggressive as the outer needles extend up parallel, then snap sharply outward during the last inch of extension.

That gave me about another 10 degrees of rearward cant. I still had problems with the needle row binding against the guide for the row in front of it, limiting how far the needles could retract.

After filing down the interference points and adjusting the needle carrier for the third row, I finally achieved full retraction!

After all of that I moved on to Row 3. It sucked with all kinds of binding and interference with the Row 2 carrier above/in front of it with the result that the two central needles tried to cross each other when extended as well as sticking up too straight. More filing. I actually had to cut my resin needle hub print to move the middle two needles closer so they would spread more when extended. Trust me, it makes sense when standing over the bench.
Before: After:

I had similar work to do on the rake and extension.
Before: After:

This row was much worse for interference and retraction issues. This took most of the afternoon to get the needle hub to retract all the way down to the limit of travel and to do so without binding. Even so, I'm left with about 1/4 to 3/8 inch sticking out. Tomorrow I will slightly shorten the middle two needles at the base to get full retraction.

So, success. I refitted both rows for a quick look to see how the overall rake and spread pattern looked. The third row is 3/8 inch from the top of full travel just so I can see if I'll be happy after shortening those two needles. Yeah, I will be. I think this looks great and very true to the game model.

Next update will cover the trials of fitting the front two rows and heading into the fitment of the control cables to finally make this thing dance.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

I finally got another video together. For the most part, it catches up to the last couple of photo posts.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

Why are the updates so slow? Because progress has been slow. I'm in my seventh (7th!) design of the retraction system because the last system had too much friction in the cable run system for the motors to overcome. I'd hoped to get away with solid channels for routing the cables but every row of needles had three 180 degree turns for the cables to make. Those turns were just too much for the motors to drag the cable around. So much for the 3D printed retraction system. I determined that I need to cut friction with lubricated pulleys for all the reversal points. That means metal!

As luck would have it, I finally got my long-idle CNC mill back together in lat summer. So, I converted all my fills for milling and designed and integrated 16mm pulleys at all the reversal points. I also added an adjustable pulley into each row to simplify tension adjustment. In other words, this new system needed 16 pulleys and shafts planned and built in. I'll add more details later, but here is the progress:

This is my little mill cutting a cable run (the part that manages the cable between the motor and a row of needles).

Here is the result of all the machining operations: Four needle row retractors, four cable runs and 16 (plus spares).

For clarity, I've marked the pulley installation locations:

Finally, here are the needle row retractors positioned in order. Each retractor represents about nine hours on machining time:

I still have a lot of cleanup on these parts as well as the attachment tabs to finish building. It will still be a few weeks before I can put it together for testing.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

This short update is a video covering a review of some older topics to get us caught up to the present work. Here we review the work done on the needle retraction chassis as well as a reveal of a new feature, the 'glittermitter'. Say what? I'm adding a gizmo to place a puff of glitter in front of the muzzle with each shot, backlit by wide beam (eye safe) lasers to give me a 'pink mist' muzzle flash with each shot. The beauty of this system is that it will work with both configurations of the prop--as an airsoft replica or as a safe and legal CON prop. I will also be able to use pink chalk dust for situations where glitter is prohibited (the smarter CONs and my house). I have a fair chance of getting tossed out if I ever distribute glitter in the house . . . . This video also includes a short look at other internal components where you can see that a lot of thought has gone into how things go together and work together.

I will try and follow up quickly with an update on version 7 of the retraction system.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

So the last post wasn't much news, but a catching up of footage that was overdue. This new video covers the material in my 24 November update--all the cool metal bits going into the animation system. I'm so sick of the animation system. Seven designs. Seven. I really hope this one works. The kicker is that this system matches the first sketches I made in my notebook years ago. I thought, "No, it doesn't need to be that complicated . . . ." Well, here we are, 16 new moving parts that weren't part of the solution before. Hopefully the added complexity pays in reduced friction and in longevity.

Beyond the animation metalwork, the four tines at the front of the gun were just too fragile when I made them to exact scale. I feared they would break in usage. One did at a CON where I was showing the work in progress. After that, I got to thinking. The answer was drill rod. Drill rod is a type of tool steel. You purchase it as a (fairly) soft metal. It can be cut, bent, or easily machined. When you have the shape you want, you heat it cherry red with a torch and drop it into cold oil. I shouldn't have to say that welding gloves and eye protection are essential when forming, heating, and hardening metal, but we do get morons cruising through the forums now and again. The cooling and hardening in oil process also straw blues the metal. Hardening the drill rod transforms it into spring steel. I have used drill rod before in making props with floating parts that needed to be tough. For a League of Legends build, we suspended the blades of the Staff of Azir with drill rod. The rod also acted as the electrical conduit.

The Staff of Azir

In the case of the Needler, I drilled a 1/8 inch hole straight back through each of the tines, measured and cut four lengths of 1/8 inch drill rod, roughed the surface to better take adhesives, heated them and quenched them in used motor oil (something a classic car hobby ensures you always have on hand). The completed, and beautifully-blued, rods were then set into each tine and recessed to contact the rear of the forward compartments and secured with first thick super glue, then fiberglass-reinforced Bondo. This ensured that any stress on the tines would be absorbed over a large area of the body.

Drill Rod lengths set into the Needler tines.

The completed job with fiberglass-reinforced Bondo anchoring the rods through the length of the nose.

So, finally, we come to the video update. Click along and see that beautiful CNC footage as the needle retractions system gets made for the seventh time, but now in 3D metal!

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Current Project: Needler Multimedia Arduino-Driven Animated Airsoft Prop (Everything the Neca Needler Could Have Been)
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Redshirt]

The necroposting warning shames me for my slow progress, but who wants to see pictures of an angry man filing, grinding and polishing reticent aluminum bits but still get no movement out of the needles? Well that's over and we have a BIG TIME achievement today. THE NEEDLES WORK! There are pictures below, but the video is what this update is all about. Take a look at the 30 round mag dump and reload sequence video. Sure, the Arduino sketch is just a simple play through, but we'll tune it some more, tie needle movements to trigger actions, magazine removal, reload button, etc. Anyway, I'm really happy to reach this point. Take look!

I have some hang ups, some attempts to move past the stops (that ratcheting sound) and some speed issues, but it is really about there. Running high-draw steppers off of a small Li-Po battery was a huge challenge. Steppers ideally move with precision and a lot of torque, but equally hold with precision. So, traditionally, a stepper uses as much electricity to hold as it does to move. Each stepper has two coils running at about 1.5-2 amps each (I have overclocked them). That's up to 16 amps! Now I don't need the holding action, so I wired my setup (and wrote my Arduino sketch) to turn on power at start move and cut it as soon as a called move is complete. Thus, I'm only at a high draw when all four are moving for the reload (less than a second and a half). Because each motor only runs for a second or two, I can risk over amping them (to a point) as heat is what kills motors and controllers. I run 50-75% over to get the torque I need. The over amping doesn't really affect the speed as I'm at max acceleration short of the motor skipping steps. I would have to boost the voltage to get a faster acceleration curve and don't want to go that route.

In addition to the need for extreme battery efficiency, cutting the power between moves keeps the motors from getting hot and compromising my PETG mountings:

The motors rest at the back and will be enclosed. I will add some sound dampening around them as they are noisy!

Here is the fitted setup with the cables and pulleys in place. Now to add the needles and shroud.

A couple of closeups of the needles fitted to the shuttles and carriers. NOT a lot of room. I have spent quite a bit of time on interference issues.

My test board was developed using the Frizting App for circuit design. Steep learning curve but you build your circuit graphically on a breadboard and once you are happy it will spit out a printed circuit board design. I am fortunate that my mill can engrave my PCB designs, but it is not prohibitive to have an outside shop make your custom boards. On the left is a Teensy 3.5, an Arduinoo-compatible product with amazing processor speed and memory. On the right are four stepper motor controllers--cheap and pretty easy to understand.

Here are all the needles in the retracted state. Not a lot of room up front for the first row.

Here’s a closeup of the front. Row 1 is a nightmare for interference issues. The outer pair of needles actually fold under the middle two in order to cram into the nose of the prop.

Here is my test and demo setup. I thought it might work better if I offered a grunt target to aim at.

So at the end of the day, a very successful couple of weeks of development—all in a hotel room on a business trip. I still have some speed and timing issues. I need to tie actions to the trigger, mag release, reload switch, and more. I also have some rows that need their attempted moves shortened to match the real-world limits of travel when the shroud is installed.

The next spiral in this development is in the actual airsoft components, so I won’t post a lot of that here except where there is a broader animation interest within the 405th’s mission. We will be working on the radar unit to make the BB’s (needles) track, so we will look at the radar application here.

Redshirt
Guess who's not coming back from the Slayer match--the guy in the Red Shirt
Signature Project: Halo 3 Working Airsoft Spartan Laser in Metal & Fiberglass

 

[Parzival]

This is amazing, watching the videos is one thing but going through and reading each post? Icing on the cake! So cool to see the development with the needle retraction setup. Great detail and explanations Redshirt! Can't wait to eventually talk with and see you on the field with this.

Much like the CB-88, I enjoy going through your teardowns of these replicas. Now having one to own, I too understand the meaning of it being an expensive toy with its' plasticy feeling. We'll see if I follow some of the methods you've done here to reinforce yours, I've got to get better with rondo at least.

Keep up the great work! Following here for sure.

 

[Lungorthin]

This build is crazy impressive. That reload action looks so good