M1 NerfBot Build1

Let's Make Robots Robots
1

 

As a quick disclaimer, I am completely self taught in all areas we'll be discussing below (I'm a Tattoo Artist/illustrator). I'm joining this community in hopes of sharing ideas, filling in knowledge gaps and having some fun building things. This is a semi autonomous nerf blaster project not a mechanized death machine, I simple love nerf guns and this is a way for me to keep learning new things fun.

My primary goal is to log the progression of this project, and use it as a platform to learn and experiment. The current revision of M1 nerfbot is a steady progression in my pursuit of building something fun and cool. Every piece of this robot/ground drone has been upgraded and replaced in a progressive order related to power/amperage draw needs, weight conciderations, torque, speed, ect as I've learned.

This version of M1 nerfbot has hit a brick wall in-terms of what I'm looking to implement and how its built so I've taken a bit of a hiatus from it while I learned the required skills to continue. I'm planning a conciderable overhaul of the entire platform from the ground up inorder to further improve on the capabilities of M1 based on what I've learned and what I plan on tackling next.

I will first go over its current revision, how it works, what it does and then I will proceed to laying out my upgrade plans based on experimenting with it and also implementing new features I'd like to learn/play with such as ROS support. 

//Current revision//

RaspberryPi2 
USB Hub / Wifi Dongle / Blue Tooth USB/ RF Tranciever
RoboClaw Motor Controller
Servo Controller
3xUltrasonic Sensors
2xFPV (Web Cam above barrel and Pi Cam on servo front lower Chassis)

M1 connects to network on bootup, runs main python script >>

M1 connects to wireless xbox360 controller and maps buttons

2 seperate video streams run (still image streams) and are sent over the network, both streams are sourced into a local network webpage hosted on M1 which takes the video streams and lays them out across the page horizontally (so the screen is split with both video streams) I then split those streams again verticle this time so I can get a fake 3D effect and put my smart phone in a pair of 3D goggles to see FPV view through the drone.

Smart Phone sends gyroscope and accelerometer data back to M1 which upon button press accepts the data and runs it through to the pan/tilt servos for the turret on M1.

Currently 2 relays control allowing power to the flywheel cage motors that launch the darts and the pusher mechanism that pushes the darts. These are currently completely stock motos in the flywheel cage and pusher box, I push 12v to them but they're really only meant to run at like 7-9v, these issues have all been addressed just not implemented. Several firing modes have been programmed in and despite the lack of motor controller/stepper mottor I've been able to successfully time out single fire as well as 3 round and 5 round burst fire. These are all mapped to the xbox controller and I have a select fire script setup as well as an attempt at calculating ammo but will eventually need to use a sensor for that instead of monitoring button clicks.

Turret also has a simple LED light, bottom PiCam is positioned low on the front of the drone on a servo, I found it was helpful to be able to check your wheels for obstructions/proximity when driving it around with the 3D FPV goggles on.

Ultrasonic Sensors act as obstacle avoidance sending a command to the xbox controller to rumble when within 6" of an obstacle, It will immedietly hault and reverse when it gets to close to an obstacle (about 2"). I've been working on a way to try and get some onscreen display data going to you'd be able to have up to date readings about proximity to obstructions when wearing the 3D goggles.

[// working on diagram drawing //]

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This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/m1-nerfbot-build1
2

War machine

There is fear in that dog’s eyes… 

Using the brackets at the front and back, you can add deflector shields (“armor”)

3

Haha

Good call on the armor, I’ve been thinking about designing and 3D printing an ABS shell that mounts in pieces to the chassis.

The dog loves it, a little to much haha. She gets really excited when I turn it on and loves chasing the nerf darts down the hallway and barking at them when they bounce off the walls. 

4

Cool Ground Drone

Cool bot.  I am looking forward to hearing more detail about the boards, sensors, firing mechanism.  Looks like a cam.  Are you visually tracking?

5

Thanks for your interest!

I’m working on fleshing out the details, it has 2 cams with video being ported onto the network so I can put my old smartphone into a cheap VR headset and use an xbox360 controller to operate it. Gyroscope/accelerometer data from the phone on my face is sent back to the robot for servo info. Viewing screen in the phone is split horizontaly (which admittedly takes a little getting used to) so the top view is from the nerf turret and the bottom view is a pi camera mounted near the underbody on a servo so you can also pan/tilt to check for tire obstructions.

I have played around with OpenCV on this a whole lot trying to get some facial recognition going but I keep bricking my pi, so I’m going to be tearing the entire thing apart and rebuilding it to solve a number of bumps that have come up as I’ve been building and working with this thing. Keep in mind I’m entirely self taught so any wisdom anyone might have is always well appreciated.

I’ll work up some images with what I’m planning for the rebuild also, might try and stream the rebuild 

6

Very cool project. I’ve got

Very cool project. I’ve got a nerf-shooting robot that I posted here, but I like yours more. I think I used the same gun you used (Stryfe Blaster), but my firing solution was to simply make a servo pull the trigger. I had to modify the insides a little because there’s a grip safety or something (it’s been a while, can’t remember).

Regarding your firing - you say you used a couple of relays to spin the stock motors. How are you pushing the dart forward into the spinning grabber? My servo pulls the trigger, and that pull is what pushes the dart forward. I’d love to get away from that and reimplement mine like yours if it means I can get away from this servo pulling the trigger.

7

Ok I see what you’re doing
I checked out your project, pretty cool and along the same lines as mine. I’ve managed to become a sudo nerf gun wizard as I’ve taken apart several blasters trying to figure out the best way to work this. I actually ended up using a nerf Rapidstrike for this project, it has a motorized pusher box in it that wires into a a circuit with a switch that is depressed as the pusher goes out and pressed when retracting completing the circuit. I have a wiring diagram on my home computer.

I’m working on a few alternate builds right now, one where I use a simple h-bridge motor controller to drive the pusher box and bypass the little switch mechanism they have. The only problem with this is timing, hard to get repeatable results. The other option I’m exploring lately is 3D printing my own pusher box with a small stepper motor so I can have more reliable results/control. I know there are a few thingiverse files for 3D printed pusher mechanisms, I haven’t tried any however.

8

Thanks for all those Nerf

Thanks for all those Nerf details. I was trying to keep my Nerf costs down, so I went with the best <$20 electric gun I could find. I didn’t have a 3d printer at that time, so I was pretty limited. I’ve since done all kinds of custom mechanisms with my 3d printer, and I definitely need to revisit my Nerf gun firing. I like your idea of designing your own pusher box. Might could take it a step further and design your own launching box too. The only thing that might need to be purchased after that would be the magazines, the bullets, and a few inexpensive motors. If Nerf corporation is reading this, they’re probably preparing to hit the “Fire” button on their team of lawyers and ceast-and-desist letters. (just kidding about the lawyers. Thingiverse is chock full of Nerf objects.)

9

Some more info
I actually found out that nerf is pretty reasonable about modding and hacking their stuff. Talked to a father son duo awhile back that run a little etsy shop selling custom nerf upgrades.
Anywho, speaking of custom launcher box, I’ve got a few of dr.snikkas custom machine aluminum flywheel cages, those with 180 size hellcat motors really sends the darts flying, average of 140feet per second. After some more research and digging however I found a guy that made a 3D printed nerf gun using brushless motors ( shoots 170feet per second if I recall correctly) and a stepper motor pusher setup (however with the weight concerns I have I’m going to redesign the pusher with a smaller, lighter stepper motor maybe a large gear to add a little more torque, have to experiment with that still. Google “3d printed nerf gun FDL-2” to find info on that build, it’s open source, he put all his files on thingiverse.

10

Youtube video

Added a youtube video of M1 in action, thanks for looking!

11

Head Tracking + 3D FPV

That combination must be a lot of fun!