Servo motor, h-bridge & IR remote

Hardware The Arduino Starter Kit
1

Hi
I'd be so grateful for some help. I'm having trouble with my project. I'm a beginner trying to learn by myself. I've tried researching it and cannot find the info.

I'm making a moving sculpture with a servo motor, that I want to control with an IR remote. Servo - specification:
Stall Torque: 12 kg/cm(4.8V), 15kg/cm(6V)
Dimensions : 54.1 x 20 x 44.3 mm
Weight: 55g
Voltage: 4.8~6V
SUNFOUNDER Metal Gear Digital RC Servo Motor High Torque for Helicopter Car Boat Robot Arduino AVR Toys Drone Fix-Wing Airplane - SUNFOUNDER (amazon.co.uk)

The sculpture weighs 300g, so I bought this servo motor for its high torque. I followed the IR remote instructions and plugged it into my laptop and the sculpture moved for a short time successfully, but then intermittently, with the motor making a constant beeping, like a SOS, then stopped working. I took the sculpture off to check whether it was this as the cause, but the motor still did not turn, with nothing on its arm. I researched and thought it was to do with insufficient power to the motor and worried about frying the arduino, so bought a motor shield L293D. Specifications:

I followed guides I found and connected this on top of the arduino starter kit board. The motor worked and it turned the sculpture when plugged into my laptop. But it gave me two more problems. How do I connect the IR remote now, as the pins are taken up by the motor shield? I cannot find an example to show me. I want to turn the sculpture from 0 to 180 degrees and ideally 90 too - having 3 buttons to stop on 0, 90 and 180 degrees turning slowly and an off switch. I got the IR remote and code working fine before the motor shield.
How do I power it without connecting it to my laptop? I followed a guide and wired it to connect to 8 x AA batteries. This did not work. No power light came on. Ditto the 9V battery supplied in the starter kit.

I tried to wire the L2930 chip as an alternative, but I only found guides for AC motors and not servo motors, and this did not work. I do not know enough about code to amend it myself. I need a wiring guide and code to follow exactly - as I am a complete beginner and the problem is I cannot find this for exactly what I want to do. Could someone point me to where a servo, motor shield and IR remote guide exists or advise me?

I also want to make sure that the circuit is safe / won't spark - it is going in a child's bedroom.

Thanks so much for helping me.

2

Did you solve your problems? If not I recommend to read

https://www.pololu.com/blog/16/electrical-characteristics-of-servos-and-introduction-to-the-servo-control-interface

  • How to power: As mentioned on that page for power you might go for a NiMH (or LiPo pack) as used for RC cars. They can deliver the current needed for the high torque (... the H bridges you use are specified for 0,6 A which according to your post worked ...). There will be a tradeoff between voltage, capacity (how long does it work before recharging is required) on one and size, weight on the other side. And of course: The more capacity the higher the hazard in case of a shortcut.
  • How to connect the IR remote as pins are taken ...
    That depends on availability of pins of the Arduino (which?) and the libraries you are using. As I understood your post, you had already something working. Could you provide your code for a view? Usually to recieve IR signals only one digital input is required. Depending on the Lib you may redefine the pin used in your sketch either as a #define or in the initialisation of the receiver object.
  • L2930 as an alternative: I recommend to stick with the shield unless you or someone else knows an appropriate library to drive the chip. The control of servos follows a certain timing...

I cannot promise that my support will be sufficient and lead to a success, but let's give it a reasonable try ... if you are still interested :wink:

3

I have used this servo motor, some data and wiring guide I don't know if it is useful for you.
You can take a look at：https://www.omc-stepperonline.com/download/iSV57T(S).pdf

4

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.