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I am just beginner, so perhaps this question is not correct. I am going to build a robot car, and I am going to power it by using powerbank. My question is : is it enough for robot at all? I mean, is it enough to connect by usb only raspberry pi, and others as motor drive will get power from raspberry (+ raspberry vamera module v2)? If it is enough what is the maximum limit of it`s power? It is my first project, so i am worrying to burn it. Thank You too much in advanve!

I meant powerbanks like this: https://www.amazon.co.jp/s?k=power+bank&__mk_ja_JP=%E3%82%AB%E3%82%BF%E3%82%AB%E3%83%8A&ref=nb_sb_noss

Dias-77
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    Yes, you should power the motors using external power, from a 3V to 6V battery/power bank. The following posts might help. (1) https://raspberrypi.stackexchange.com/questions/96515/why-dont-my-motors-rotate (2) https://raspberrypi.stackexchange.com/questions/99460/motor-wont-stop (3) https://raspberrypi.stackexchange.com/questions/98513/program-my-robot-with-python – tlfong01 Jul 24 '19 at 01:02
  • Thank you for prompt reply and helpful links! I read that 9V battery could burn raspberry, and to be honest i am going to use powerbank to protect it. – Dias-77 Jul 24 '19 at 01:17
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    Yes, even 5V power connected to a Rpi GPIO pin would fry the Rpi. The "Build a buddy" tutorial mentioned in my links are good for newbies to get started. Using L298N driver and 3V to 4.5V battery pack is good. – tlfong01 Jul 24 '19 at 01:23
  • Yes, that was great tutorial! Thank you so much! There were used 4 batteries is it enough? Because the sensors and other details in my project a little more. I am sorry for asking again – Dias-77 Jul 24 '19 at 01:42
  • 1.5V x 4 = 6V is only for driving cheapy yellow toy motors. That project.rpi.org tutorial actually suggests to use Lipo power banks, which are powerful enough for bigger projects. They also refer to GPIO.ZERO which has built in advanced motor control functions, and also stepping motors control. Sensors usually don't use much power. But toy servo motors, solenoids, even small, are power hungry. In short, just try to start with a 4.5V/6V battery pack, L298N motor driver, 2 cheapy yellow toy motors. The principles you learn can almost directly used in serious/industrial grade projects. – tlfong01 Jul 24 '19 at 02:08
  • I am sorry if i`ve mistaken, but I suppose in this tutorial those batteries are used to connect to L298N). Is it safety, f.ex to use 18650 batteries for motor driver-L298N, and powerbank like this : https://www.amazon.co.jp/s?k=power+bank&__mk_ja_JP=%E3%82%AB%E3%82%BF%E3%82%AB%E3%83%8A&ref=nb_sb_noss to power raspberry? – Dias-77 Jul 24 '19 at 02:10
  • @tlfong01 Thank you so much, sir! – Dias-77 Jul 24 '19 at 02:13
  • Yes, I actually started humbly with a 3V battery. Then I tried 3.7V 18650 Lipo battery. Usually those toy motors runs at 3V, 4.5V, 6V. Higher voltage means higher speed. If you search in this forum for "L298N", you can see other experts using 12V or even 24V powered motors. But as I said, start small, ... – tlfong01 Jul 24 '19 at 02:15
  • @tlfong01 I understand you. It was so kind of you to spend your time! Thank you again! – Dias-77 Jul 24 '19 at 02:19
  • And those expensive amazon power banks your mentioned are actually for smart phones and laptops. They are classy, slim and small. But usually smaller guys store smaller electrical energy. So my ugly looking, DIY cheapy Lipo 18650 x 2 power bank actually runs toy cars faster, and longer. – tlfong01 Jul 24 '19 at 02:21
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    You are welcome. I am an electronics toys hobbyist. When I was young, I earned a living as a technician in a toy factory, making toy cars and even tanks. – tlfong01 Jul 24 '19 at 02:24
  • I start to understand, by using another modules as dc dc protector, or charging protector board as mentioned in the tutorial are safe raspberry pi from burning? – Dias-77 Jul 24 '19 at 02:25
  • And should I charge L298N and raspberry separately as shown in the tutorial? – Dias-77 Jul 24 '19 at 02:29
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    Ah, that is another thing. I do use Lipo 3.7V x 3 = 11.1V. Then I use DC/DC adjustable voltage regulator module to step down 11/12V to 3V to 6V for DC motors and toy servos. The regulators usually has current limiting, say 500mA up to 3V, usually. So it is safer than to use battery packs which do not have current limiting or short circuit protection. – tlfong01 Jul 24 '19 at 02:30
  • Yes, you can forget Rpi for now, and just use L298N and one toy motor to start with. You can use jumper wire by hand to input 3V power to the L298N input, to move forward, backward, stop etc. Then you can use Rpi GPIO to replace your stupid human hand. Rpi GPIO can apply input power on and off very very fast, called PWM, which are for ninjas. I think I am going to fast, it takes some time from newbie to upgrade to ninja. So I will stop here, let you drill your kung fu for say, two weeks, and come back to let me know if you have fried your motors or the Rpi. – tlfong01 Jul 24 '19 at 02:37
  • In case you found the tutorial I recommended too brief, You might to read the two tutorials in MagPi84: (1) Page 36 - Build a low-cost robot, (2) Page 44 PWM, servo, sensors etc. And as I said, PWM and sensors are for ninjas only! – tlfong01 Jul 26 '19 at 02:04
  • I found it! Thank you! – Dias-77 Jul 26 '19 at 04:42
  • I checked motor drive L298N, with a simple 18650 batteries, it is working. I am going to use for Rpi old powerbank, if it will be not enough, i will try to use another type of battery. – Dias-77 Jul 31 '19 at 05:48
  • Well, usually 18650 battery is strong enough to move L298N driven toy motors. I forgot the 18650 current limit and current requirement of those yellow toy motors. Perhaps you can check it out for everybody's reference. – tlfong01 Jul 31 '19 at 05:56

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Power bank is a poor choice for raspberry pi. It will work but I don't think it will work that fine. You have to make something that gives you 5V 3A power. Here is how you can make one, 1. 12V lipo battery 2. UBEC/BEC(5V-3A)

With these two you can do both of your things(car+pi) BEC is the important part here. This is the part that converts 12 V to 5V with 3A.

Sohan Arafat
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