46 replies to this topic

[Kingbob]

Hey all

 

So have been stupid busy the last few months and havent done much nerf work, but I scored a cheap Hyperfire on the weekend, so thats inspired me to do some more modding!

 

First was my basic MkI Arduino controlled Stryfe and Rapidstrike: http://nerfhaven.com...nd-rapidstrike/

Then my MkII with an OLED and extras: http://nerfhaven.com...hot-counter-v2/

And then the MkIII with a fully reworked Stampede: http://nerfhaven.com...controller-mk3/

 

Now its time to see what else I can add in to a MkIV !

 

I've already removed some of the locks and put in better wiring to the Hyperfire, but electronically it's still stock.

The obvious things i added in the previous guns will be there:

- Mag size detection

- Round counting

- Voltage display

- Current draw display

- Jam door open detection

- Safety switch

- Single shot, three shot, full auto shot selection

- Stopping shooting at 00 rounds

- Buzzer for safety/no ammo notification

 

I'll use a 1.8" colour LCD, so i might add a way to change the colour using a trimpot.

 

Any other suggestions for things to add in? The Hyperfire has a stack of room in the front end so I can fit all sorts of things in.

[ENP10]

A toster! Jk

The only thing I could think of would be to put some sort of intergration in the front.





Maybe a battle song speaker?

Edited by ENP10, 02 November 2016 - 08:36 AM.

[CaptainSlug]

- Mag size detection

I saw how you did that in the other thread and it was pretty clever. You could potentially accomplish the same thing with reed switches if you find that constant mechanical interfacing with those switches wears them out, or you can't make the assembly small enough.

 

You can mount small magnets between the ridges on your magazines that trip certain combinations of reed switches to denote magazine size.

[DjOnslaught]

I saw how you did that in the other thread and it was pretty clever. You could potentially accomplish the same thing with reed switches if you find that constant mechanical interfacing with those switches wears them out, or you can't make the assembly small enough.
 
You can mount small magnets between the ridges on your magazines that trip certain combinations of reed switches to denote magazine size.

That's actually the way I'm gonna be doing it, when I finally get another stampede that I think I can pull it off in.

[DjOnslaught]

Remember the runaway problems you had when powering on the blaster on the mk3? I just thought of something to help avoid thathe and may be easier then a pull down. You could try using a mag lock that let's everything power on but prevents pusher motor operation without a mag inserted, kinda like they normally work but it would still allow for motor rev without the mag.

[Kingbob]

I saw how you did that in the other thread and it was pretty clever. You could potentially accomplish the same thing with reed switches if you find that constant mechanical interfacing with those switches wears them out, or you can't make the assembly small enough.

 

You can mount small magnets between the ridges on your magazines that trip certain combinations of reed switches to denote magazine size.

 

Actually if you read all the way through, i got rid of the switches and used hall effect sensors with magnets.

Remember the runaway problems you had when powering on the blaster on the mk3? I just thought of something to help avoid thathe and may be easier then a pull down. You could try using a mag lock that let's everything power on but prevents pusher motor operation without a mag inserted, kinda like they normally work but it would still allow for motor rev without the mag.

 

I solved that, it was just that one of the switches had come loose from its mount and wasnt registering a press properly. Couple of drops of superglue and all good.

[Kingbob]

I might be able to add a muzzle velocity measurement as well. Use an IR sensor at each end of the barrel, and just measure the time between them breaking as the dart goes through.

Its a short barrel though, so may not be hugely accurate.

 

I'm also going to have another go at measuring the flywheel speed. I think the reason i had problems last time was simply the speed of the processor not being able to keep up with the interrupts from the sensor. The arduino nano i used has an atmega328 processor which runs at 16Mhz which isnt exactly zippy. This time i'm using a board with an ATSAMD21G18 ARM cortex M0 processor, which runs at 48Mhz. Hopefully this can keep up with the sensor. Also has an onboard JST power connector for a LiPo, and built in LiPo charger circuit if connected to USB.

And has way more flash and RAM which solves the graphics library issue i had previously.

 

I could add an ultrasonic sensor to the front, maybe tie it to a second screen on the top of the gun, do an Aliens style motion detector

[DjOnslaught]

Holy crap, what kinda arduino you sticking in this beast a mega?

[Kingbob]

Megas have been outclassed for a while now. Look at the arduino zero, zero pro, M0, M0 Pro etc. Half of them have built in wifi or bluetooth now. The new Primo even has NFC built in, and the new Star Otto has several times the grunt of a Mega. 

 

Could even use an ESP8266, they have 4MB flash and run at 80Mhz and built in wifi, but are a bit low on gpio ports unless i add an i2c expander.

 

I have a few Raspberry Pi Zero's too, thats got 512MB of RAM and a 1Ghz processor in a board not much bigger than an arduino nano. But my python skills are way rusty, and a nerf blaster that runs linux seems to be overkill

[DjOnslaught]

Wow do I feel behind on my tech

[Kingbob]

I've started prototyping it on breadboard, and poking around the guns insides to decide what will go where etc.

There is so much space in the front end of this gun its ridiculous. I could fit a lipo in the front and cut off the whole rear end!

 

I think shot detection in this one will have to be IR based since its full auto, obviously counting trigger pulls wont work.

So right after the flywheel unit i'll look at putting in an IR LED/Transistor pair to detect a dart passing by. If i can fit an IR pair at each end of the barrel tube, i might be able to do a dart speed calculation.

 

I've settled on using a Feather M0 Basic board from Adafruit. Ordered a couple a while back but hadnt gotten around to using them yet.

Edited by Kingbob, 05 November 2016 - 12:48 AM.

[Kingbob]

Since I already have code from the previous versions, i basically just have to adapt it to a new board with some different options.

So far, have the following working on the breadboard:

- LCD screen

- Hall effect sensors for magazine size detection

- Magazine insertion detection switch

- Joystick

- Buzzer

- A new "mode" switch for something else i might add

 

For now i wont add in a "safety" switch. Had one on the Stampede but thats because there was a switch built into the gun for it. Probably wont add a jam door switch detection mechanism either.

I've soldered up an IR LED/transistor pair, just need to code them up to work as the counting mechanism when a dart passes by.

 

[Kingbob]

Current diagram, though not everything is connected on the breadboard yet.

 

[DjOnslaught]

Have you considered the photo ir sensors? The ones that are both parts on a single piece, I was going to use one initially as my shot counter when I was designing my stampede.

[Kingbob]

Yeah but it was cheaper to get them separate. Plus the gap wasnt wide enough on them.

[DjOnslaught]

Ah as long as it works right

[Kingbob]

I've tweaked the design a bit. I've added in a pot read into an analog input which will determine the color of the screen. Can set it to preferred color without adjusting code that way.

Had to add in a level shifter, the buzzer is a 5V device, but the Arduino M0 board i'm using runs at 3.3V so cant drive the buzzer by itself.

 

I was previously going to leave the firing mechanism alone, not arduino connected but changed my mind. So have added a switch in for the trigger, which will close a relay to drive the firing belt motor. Will let me stop it from running when out of ammo that way.

 

I have one single IO pin left, cant think of anything else to add, suggestions?

 

(btw i obviously havent drawn in the +V and GND connections in the diagram. CBF lol)

Edited by Kingbob, 15 November 2016 - 01:38 AM.

[DjOnslaught]

I think have a unused pin might be useful in case of a bad one

[J51Mustang]

I was thinking of modding a hyperfire with a brushless motor setup similar to how Eli Wu modded a Rayven (link to youtube vid where he was featured: ) and got it to shoot an astounding 180 fps. It is quite interesting how he used outrunner brushless motors as flywheels.

[Kingbob]

Wow, yeah i'd never thought of using outrunners!

 

Impressive engineering work, but not quite my style. I like my blasters to appear minimally modified, the electronics should look like they're part of it, not quite so added on. But thats my personal preference. 

 

Now i'm off to look at outrunners

[Kingbob]

The last of my parts arrived today, will start installation tomorrow

[JospehSquared]

What are you planning on using to run this beast?

 

Do you use separate Lipos (or whatever you are using) to run the flywheels, pusher mech and all the electronics?

 

Really excited to see what this turns into!

Edited by JospehSquared, 03 December 2016 - 12:53 PM.

[Kingbob]

I have a bunch of lipos in my parts box. Probably use a 2s 4000mAh 20C pack, had it spare for a while. At the moment the motors are stock so no real issue there. 

Havent decided whether i'll end up putting in some rhinos or go brushless.

 

Will run it all off the same motor, have a small 5V regulated power supply that i'll use to run the electronics. Wont draw much anyway.

[Montymarks]

Ayy!

You got the code for that?

I kinda undestand C.

 

-Montymarks

[Kingbob]

Ayy!

You got the code for that?

I kinda undestand C.

 

-Montymarks

 

Not quite finished yet, still getting it how i want it, but its based on the version i used in my stampede, follow the link at the top to find that.

So far have changed the screen layout a bit, doesnt use the same motor drive and firing detection code though.

 

Will post the code once its done, but the Stampede version will show you most of it.