Hello im David and i wanna build robot for my school project. I ve read robot tutorial here on page but i will still need help with some stuff. i dont know which components should i choose.
i wanna make it quite cheap materials for body wont be problem. It should be big cca as A4 paper sheet i have something in my mind but i wanna make it depending on how much space will electronics take.
electronic components :
I decided to choose Arduino uno
i will need 2 gear Dc motors that will be good enough to move my tank( i saw somewhere 300 rpm should be enough )
duo Dc motor controller
i want it to be controlled wirelessly- i have radio controlled car with controller at home so maybe i can use some stuff from that to controll it. also there is nice slot for 3x 1.5V thicker type
or bluetooth to control it with my smartphone if it wont be hard to set up
it would be good to make robot autonomous too ( and maybe have some switch between control and autonomous) so ill probably need some optical sensors, other alternative would be to control robot with my voice but i dont know how complex it will be to program or set because Im new to this.
I dont want to make it so expensive max should be somwhere near 120€
About body i want to make tracks sam as instructables.com/id/How-to- … -for-very/
i have one big aluminium plate thick 0.2cm but i dont know yet how to set wheels in tracks so it wont slip same as on that site above also i dont know how will i mount motors to wheels yet.
i will appreciate any help from you.
Always one of the best choices for a small robot project.
robotshop.com/en/arduino-uno … rev-3.html
It all depends on the weight and configuration of the robot. Take a look at this free tool to get an idea of the torque and RPM each motor will need to provide:
robotshop.com/blog/en/drive- … -tool-9698
The dual DC motor controller will need to be able to provide the power that the drive motors require.
robotshop.com/en/brushed-mot … llers.html
Yes and no; that system is made for a specific type of motor and if you change that motor, the system might not work.
Hacking an existing production robot to use its parts might not be the easiest as a first project.
You’ll need to code the Arduino to receive Bluetooth commands, and your phone will also need an App which sends those commands.
One step at a time 
That should be possible, especially if you’ll be making many of the parts yourself.
You’ll need sprockets connected to the drive motors - like a bicycle uses.
So about the motors i was looking and i found pololu micro metal gearmotor that looks good and its ni that expensive so 250:1 has more torque and less speed than 150:1 ? I dont know what weight will my robot have. 2 tracks made from 2-4 bicycle chains depending on if i can cut somehow 2 into 4 or if i wanna make it higher like usual tanks have so it can go over obstacles easier, pvc tube all the electronics inside 0.2 alumiinium “box” . Ive chosen 3 motorcontrollers i want it to spin motor cw or ccw so it can turn my robot u got the idea
robotshop.com/en/l298-dual-h … oller.html
What is easiest way to control robot ? Autonomous
Rc (i bet ill need to make controller so i will need some other electronics for that ?)
Bluetooth ( this will be quite ok for me to control from my smartphone but will it be as continous and fast as usual rc controlled cars ?)
Those sprockets might be problem because ill probably need it precisely for my robot to fit not rly sure about that in a shop here, i might look at bike shop or toolshop.
Can you provide a link to the motor you are considering?
What doy ou mean by link ? like wheels connected to motors by sprocket ? also u havent answered my last questions, im kinda in hurry 
A ULR or web page link so we can see which motor you’re considering.
The easiest way to control a robot is R/C - the hardest way is autonomous.
If you choose R/C you don’t need to do any programming and don’t need a microcontroller.
Bluetooth will likely need programming and is between R/C and autonomous. It really depends on your needs.
A bike shop should have the sprockets and chain you need to build a custom track setup.
Oh gosh 
i got little bit confused robotshop.com/en/pololu-298- … or-hp.html
here it is there are a lot of others almost same but gear ratio is different
About controlling ill take that bluetooth do you have some tutorials for programming arduino uno for bluetooth here on page ? I guess ill order everything after ill be sure abou motors and ill stay in touch with my progress
The motor you linked to is really small and not powerful at all. The gear ratio is the highest of the series, which means it will rotate very slowly. You’d see if you ordered it that it’s disproportionally small compared to a bike sprocket. You’d need something more powerful. Unfortunately we don’t have much regarding Bluetooth control since most require that the code be specific to a microcontroller and motor controller.
Hello i have to change my project after discussion with my teacher. She said that if i make controlled car with bluetooth it will be kinda pointless and that i should make something that has practical use. So i’ve decide to change my plan. Do i have to make new forum discussion ? And can i somehow be in touch more often per day with you or somebody that will help me ? maybe private message ?
The new project should be R/C controlled robot with camera that can move on terrain and stream it. So as you said earlier i dont have to have microcontroller if its R/C.
so i will need only motor controller, 2x motors, camera and body with tracks ?
here are controllers that im considering, im not sure which to choose
robotshop.com/en/dfrobot-4-8 … oller.html
robotshop.com/en/10a-5-25v-d … river.html
robotshop.com/en/l298-dual-h … oller.html
here are motors that im considerindg im not sure which to choose
robotshop.com/en/pololu-12v- … coder.html
robotshop.com/en/ghm-13-spur … motor.html
robotshop.com/en/pololu-12vd … motor.html
robotshop.com/en/ghm-16-gear … shaft.html
here is some my old R/c car maybe if i use controller and motor controller for that ? at least that battery holder should be to use.
Couldn’t you just opt for a WiFi camera like an old GoPro and strream the video to your cell phone?
yeah but i dont have one thought, can look on internet.
what about other stuff ?
Any RC robot or car can act as the base. It seemed like you already had everything you need one from the photos you provided of the R/C car.
You could potentially gut that R/C car and create a new base, but that’s really up to what you need to fulfill your requirements.
so i have to just get better motors and change that old weak motors on my car to new and i can control it like that ?
Do you really even need to change the motors? Note that the electronics which came with the car are specifically designed for one motor; if you try to use it with a more powerful motor, the motor driver likely cannot provide the current required and will fail. Also, if you want to reuse that chassis, there’s a lot to consider when trying to use different motors besides just the electrical specs; fitting the motor with everything is not necessarily easy (dimensionally speaking).
Yeah but if i use old motors it o
Wont have enough torque for my tracks
So i will need to buy controller too but how will i control it, also can u help me to choose from motors and controllers which i listed before ?
The four motors you indicated would all be ok for a medium sized robot. If you indicate which one you’ll choose (based on torque and RPM), we can suggest which motor controller is best.
Would you prefer a motor controller which accepts RC input from a standard hobby RX system?
So ive chosen robotshop.com/en/pololu-12v- … coder.html
motor controller should be dual since i will use 2 motors and it should be able to control them on reverse so robot can turn.
i guess input from a standard hobby RX system would be good but im not sure what does it mean
You need a dual DC motor controller which can provide at least 70mA (0.7A) and accepts R/C input.
robotshop.com/en/rc-motor-controllers.html
Ex: robotshop.com/en/sabertooth- … =RB-Dim-30
An R/C system is something like:
robotshop.com/en/spektrum-5- … =RB-Hoh-01