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Welcome to the Newone wiki!
Uptodate documentation: https://www.open-ats.eu/docs.html
documentation This is a documentation for building the vehicle/software by yourself. The documentation consists of three main sections which are mostly independent from each other: -programs -3d-printing -electronics
table of content
programs server
electronics raspberry pi step down converter 4g modul electronic speed controller servo motor battery battery management system
3d-printing print assembly slicer settings springs connections
features
programs • programs for access the vehicle over the internet • program for controlling motors • program for videostreaming • open-source software, all programs written in python (not secure but easy to understand) • programs using udp for low latency • opencv for taking video and displaying them, good for future AI • all programs can as well be used for standard rc-cars, airplanes or boats with pwm input and even for stationary surveillance cameras.
3d printing • open-source hardware, hole car 3D-printable • 3D-printed ball bearing (printable in one piece without any support) • 3D-printed flexible tires (airless, filaflex 82A) • insertable metal springs on all axis • assembly with only M3-screws and threaded brass inserts • support structures rarely required, low part count, easy assemply
electronics • two individual servomotors to steer the front wheels • two individual brushless motors directly integrated into the rear wheels • (inwheel, hubmotor) • raspberry pi • blheli32 ESC's • 18650 cells with BMS (25.2V) • low cost
programs There is only one python program for everything: videostream and controlling for the vehicle, groundstation and server. All in one single file not more. The programmes are compatible with Linux, Windows and Mac. A readme file for setting up the programms is included when downloading or here. Here you can download the programs. Here is a video where it is shown how to use the programs: link. You can test our video streaming program with no additional hardware.
server A server is needed for controlling the vehicle over mobile internet. Any server will work as long as there is python on it and the server has a static ip. But its not a necessity, the vehicle can also drive connected over WLAN without a server, just open the server program on your laptop additionaly and change the IP addess.
electronics The documentation of the electrical components is split into the individual electronic parts. The operation is controlled by a Raspberry Pi zero 2W that tranmites video and receives commands over the internet using a 4G stick. The vehicle is powered using 6 18650 liion batteries connected to a battery management system (BMS) module. The BMS is connected to a power distribution board (PDB) which regulates power between the Pi, 4G stick, two step down converters(one for Pi + 4g stick with 5V, one for servos with 7V), two servo motors and two ESCs. The ESCs are connected to the two brushless motors. If zou dont know how to connect everthing here is the 3D model: link
raspberry pi The Raspberry Pi is a small computer which will control the vehicle (controlling motors, get video data, communicate with the 4G stick). Basiclly it's the brain of the vehicle. If you use our Power ditribution Board the Pi is connected with it via a "eselsbrücke PCB".
stepdown converter The raspberry pi, 4G modul need 5 volts but most of the time a battery delivers more than just 5V so we need something to convert high voltage to low voltage. This task can do a stepdown converter for us. Connect it on the IN terminals to the batteries. On the step down converter there are a potentiometer where the voltage can adjusted. The servo motors also need 7 Volts to work best, so an additional step down converter is needed.
servo motor The servo motors are needed for steering the vehicle. It has two individual servo motors, so you can steer the two front wheels. They are smaller than the main ones. They have a gear inside to convert the a high spinning low torque electric motor to a low speed, high torque motor, which is needed for steering. If you use our power distribution board there are two 3 pin connetions for each motor
internet connection WLAN For testing, your phones hotspot or your WLAN does the same job. Once this works you can upgrade to a 4G connection. Just open your server on the groundstation (Laptop) too. You can test that right now: run the main.py-file tree times and select.
4G Stick The 4G stick gives the vehicle access to mobile internet. Of course, a SIM card is additionally needed for it. The Raspberry Pi will comunicate with the 4G stick over WLAN (also over USB possible with Pi 4). The 4G Stick gets power from the 5V Stepdown converter. If you use our power distribution board, there is a 2 pin connection for it. Most of the time the wireless login information is on the back of the module. Try to access the WiFi with your phone first and try to load a webpage, to be sure you have internet access. Also, try to find out the IP adresses of the connected devices, because we will need that later to find out the IP address of the raspberry pi, to ssh into the pi with our laptop over the 4G sticks WiFi.
connections To connect all the components together we need of course connections. 6.3 mm crimp connector can be soldert directly onto the power distribution board, no additional wires needed no soldering needed, just crimping cheaper, smaller and lighter compared to other options (bulled connection) easy to draw and to adjust in pcb software available shrinking tupe We dont use xt60 connectors because they are hard to solder, a big shrinking tube is needed and they are relatively expensive. Additionally we can solder the crimp connector directly onto the PCB, need to solder both plugs on a wire.
3D-Print All structural parts of the vehicle are 3D-printable. Even the bearings in the front wheels, the flexible tires, the battery case, and the support structures of the spring. the stl-files are ready to be thrown into your slicer program and then ready to print (take a look at our recommended filament and slicer settings for best results). The whole vehicle was drawn with blender. Here is the link to download the STL-file
recommended filament and slicer settings solid filament: PLA PLUS SUNLU profile: Dynamic Quality wall Thickness: 3mm 2mm is a bit less top bottom thickness: 3mm 2mm is a bit less top/bottom pattern: Line #Concentric doesn't work well infill density: 20% gyroid print temperature: 235°C not more otherwise wired stringing happens! 210 is to less, part has no strength --> delamination build plate temperature: 50°C realy needed for bigger parts, they will for sure warp otherwise flowrate: 103% better layer adhesion, waterproof, not more its to much infill flow: 103% Initial layer Flow: 103% infill support: 103% to modify first enable "support" minimal support area: 8mm so small holes for screws are not filled with support speed: 150mms support: everywhere flow: 100% will show after "support" is enabled enable support interface disable build plate adhesion type: none z seam alignment random importantn otherwise you get that horizontal line somewhere
flexible filament: FILAFLEX 82A prinable with a bowden extruder(tested on ender 3 pro) profile: Dynamic Quality wall thickness: 4mm top/bottom thickness: 4mm top/bottom patter: Concentric infill density: 100% print temperature: 220°C temperature is very important, is the temperature to high the material is too fluid, and wired strining and irregularitys in the print are the consequence build plate temperature: 40°C otherwise warping for SURE happens flow: 103% speed: 20mms generate support: everywhere build plate adhesion type: none z seam alignment: random important otherwise you get that horizontal line somewhere
tires The tires are made out of flixible filament 82A. Dont try to print them with TPU 95A, they will be to hard and they will have no grip on the ground.
bearing The bearings are printable in one piece with minimal support structure needed. They can be 3D printed in normal PLA/PLA+, but we recomend using Nylon because of good impact resistance and low friction.
axis The vehicle has 4 springs on all axis but no dampening. The spring can be inserted, no complex mechnaics needed.They can be 3D printed in normal PLA/PLA+, but we recomend using Nylon because of good impact resistance and low friction.
components holders The compnents have all there space inside the vehicle. The components are sandwitched betweeen Mainframe and cover. So no need for srews or glue.