Arduino module for servo and motor control

Hello, I'm brand new in this forum and must first say I'm a little overworked. I do not know if I should ask which question and which rubric. If I am already wrong here with the creation of this post then I apologize now already for it.
I would like to create a project. But I am absolutely new in this segment and try to answer all my questions in this regard myself as in google or on others because.
Now, to my question to you:

  1. I buy a model, which is operated with chain drive. As far as I know, these are 2 electromotors (right-left) which are operated with 9volt 1200mA.

  2. on this model, in addition, a movable arm, with 6x 7.2 volts servos betrtieben (lift, lower, turn, grip ect)

  3. there will be a camera mast, with 2 servos (lower-lift, turn)

Now to my main question:

I will use a Rasperry Pi 3 Model B. This can be operated via a 5volt usb bank since it must work independently. Model is remote controlled.

I need an Arduino controller for the 2x 9 Volt motors for driving and steering, which must be controlled via the rasperry.

The servo arm with the 6x servos must be separate from driving and steering. (I have found a module with a Sony PS2 controller and a control board for 32x servo.)

Is there an Arduino module with which I can handle all these requirements? It is important that I can use the Arduino module with the PS2 controller.

If this is not the case, I do not know how to do the project.

I really hope you can help me. Because otherwise it will be nothing.
I thank 1000 times for your help and considerations and I look forward to answers. Thank you

The Arduino cannot drive the track motors directly. You need a motor controller board or transistors. The Arduino will send a 5V or 3.3V signal (depending on your board) and the motor controller or transistor will switch the 9 volts. The output from the Arduino will typically be Pulse Width Modulation (PWM). If you don't know what that is then Google it or ask.

If you need both forward and reverse for the motors then you will need an H-Bridge or a motor driver board that has both PWM and direction. If this is all new to you, then you might want a motor driver boards that is controlled by a serial link (UART, SPI or I2C). Sparkfun and Pololu have them available.

Controlling RC servos can be easier if they are powered by the same voltage as your Arduino (or RPi). You can use the servo library to control them. If the servos are powered by a higher voltage then you need a level shifter or transistors.

We would need to know more about your PS2 controller board to understand how it interfaces.

Hello, many dear thanks for the fast and detailed answer :slight_smile: With the H bridge I thought to myself. However, I see the biggest challenge in the programming of the servos and the h bridge. The board with the ps2 controller I found here: https://www.aliexpress.com/store/product/32-Channel-Servo-Control-Board-Robot-PS2-Controller-Receiver-Handle-for-Arduino-Robot -DIY Platform / 614216_32660022901.html
But does it deprive my knowledge of how I can combine these with the adruino board and the bridge?

The servos should all be operated with 7.2 volts, since the load will be relatively large (over 5-10 kg)

I cannot think of any reason why an Arduino cannot control your two drive motors (via suitable H-bridges) and your 6 servos.

An Arduino can easily receive messages from an RPi telling it what to operate.

...R

The problem with buying from Aliexpress, eBay or many of the Chinese suppliers is that you get no useful documentation. I've looked at the web page and I don't know if the 32 channel servo board will come programmed with the Arduino boot loader or not. I have no idea how the PS2 controller connects to the board.

Try hooking it up and see if the Arduino interface will talk to the board. If not you can search for how to program the Arduino bootloader. It might work, but they have obscured the markings on the micro so it could be a completely different micro.

I'm sorry I wish I could be more help.

Thank you for your quick reply.
With the chinese copies of the control boards I see exactly the same. The problem is that it is too insubstantial with power or circuit diagrams.

I am willing to use adruino, although I have no idea (shy)

Hello Community, I have now my project thought and came to the conclusion that I want to try it differently. I will buy a 6wd robot.

But now I have more than ask, since I am totally new and have no knowledge about adruino and raspberry.

My thinking looks like this: the robot has 6 motors for driving and steering (6 axes)

The crane: this has 7 servos, lifting, turning, lowering and gripping.
The servos need 7.2 Volt as well as the traction motors.

Now comes the difficult, for me in any case, because I have no previous knowledge.
I want to control the robot with a gamepad over wlan, not over bluetooth, very important (back and forth, right, left) the crane, must be controllable over the analog sticks.
As I have in experience, I must use the raspberry, because the drivers for the gamepad must be installed. Because the robot is needed outside, I see only the solution over the wlan. For this I found a wlanpowerker with 8W performance, since the robot must be controlled up to 1km in built area.
Is it possible, and if so how, via the wlan connection of the raspberry over the amplifier, to drive the adruino board, in order to enable the drive, as well as the servicing of the crane? I hope someone has an idea, or at best

If, by "wlan" you mean wifi then that won't work over a range of 1km unless there are multiple base-stations it can connect to - hopping in the way that mobile phones do.

Wireless over that distance with obstructions caused by buildings and such like will not be easy and may not be possible without using a frequency that needs a licence. Perhaps it could be done with a 3G or 4G mobile phone or dongle on the robot.

And if you are "totally new and have no knowledge about adruino and raspberry" then this project is much too complex for you. It would be a challenge for an experienced programmer. Start with something simpler that you have a reasonable chance of completing.

...R

hank you Robin2 for your clarifying words. I have now found out by myself that a wlan solution is not to be realized. Because I want to forget the idea and the associated project, there is probably only the possibility over bluetooth. So the distance is very limited, but it should go with a servo board which has a bluetooth interface, or is I too here in the complex? H bridge and servo control directly over bluetooth? Best regards

PROLIX:
or is I too here in the complex?

The complexity has little or nothing to do with the choice of wireless system.

It is the whole project that is complex. From what you have said you don't yet know how to create a simple program on an Arduino or an RPi.

...R

If the entire area of operation is covered by Wifi, then it can be done. As mentioned, 1Km wireless range requires more than the simple radio links we normally see here. I have not done much over Wifi so hopefully someone else can speak up about that, or ask specific questions in the networking section of the forum. Also, everything I've done has been with the low-end Arduinos, which may not have the processing power to handle networking and driving the motors and servos. I would probably do the networking and master control on the RPi and only use Arduino's as slaves to control the motors, servos or sensors if needed.

XBee Pro communication modules with a good antenna can easily cover this range and don't require a lot of processing power for the interface.

You want to achieve a fairly complicated end product. I would break the project into building blocks:

  • Basic RPi software - If this is all new to you, go through some beginner tutorials to get familiar with the RPi and programming
  • Basic Arduino Software - Same thing for Arduino
  • Connect to Controller - Be able to read the inputs from the controller, just displaying the data on a screen
  • Basic Communication - Be able to send data back and forth between your RPi and another RPi or Arduino via wireless
  • Distance Communication - Verify the communication link works over the required range. What is the max distance? What kinds of messages or errors occur when the distance is near the max. Develop a way of identifying the conditions and clearing any faults. Learn about error checking the messages
  • Motor Control - Be able to control the speed and direction of a single motor, then be able to control it remotely
  • Drive Control - Be able to control multiple motors and/or steering to maneuver the robot around
  • Servo Control - Be able to control a single servo, then be able to control remotely
  • Arm Control - Be able t control the position of the arm using multiple servos. This will involve some involved geometry and/or lookup tables
  • Stop and Think - Now that you have the building blocks, what information needs to be sent between the controller and the robot? Do you want to only send "go to x position" info and do all the calculation at the robot or do you need to do all the calculations at the master control and send individual commands for each motor and servo?
  • Put it all together

It sounds like a great project and you will learn a lot if you see it through. Best of luck.