Servo Motor without PWM Controller


#1

I use 2 servo motor for control pan-tilt camera, i tried to add a control in Cayenne but it want that i select PWM Driver, now i dont understand if it mean software driver (i use ServoBlaster driver to control it with terminal commands) or a PWM Controller, can i control this 2 motors without a PWM Controller, connecting the motors directly on GPIO?


#2

Welcome to Cayenne!

Unfortunately as of right now you will need a PWM controller (PCA9685) to output PWM with Cayenne. Software PWM is being worked on but I have not seen any estimate for its release yet.


#3

Thank’s a lot


#4

You could alternatively use an Arduino :slight_smile: We recently released Arduino integration, check it out and let us know what you think.

-B


#5

Just a thought but Scratch GPIO controls servo’s beautifully. You could write a background scratch GPIO servo control script that auto starts and responds to pin state changes from a crude 4 button paddle on the GUI some how like

  • Servo A CW
  • Servo A CCW
  • Servo B CW
  • Servo B CCW

The Pi has huge potential as a direct driver for servo and I too am always on the lookout for the direct jumper wire solution. Amazing that you can even transmit FM stereo from the GPIO pins !

~ Andrew


#6

You mean use the Pi to control the duino, which will in turn control the pwm controller?


#7

Well, with our new Arduino integration, you could just control the servo directly from Arduino :slight_smile:

http://community.mydevices.com/t/about-the-arduino-beta-category/810?source_topic_id=855

-B


#8

Will there be a possibility in future releases that there is no need to use the PCA9685?

I want to make use of the native PWM on the RPi3 in order to control a light dimmer and not make any use of additional hardware as I have created my own sort of “PiHat” in my home automation project.


#9

The Cayenne team will be working on user requests after the MQTT release, so hopefully they will get this added in shortly!


#10

Any idea when the MQTT release is scheduled?


#11

we’re havin’ some fun now! :o


#12

Servo direct from the Pi header is Very Tidy and I use it a lot in demo mode from Scratch GPIO = Very Smooth and ‘intelligent’ I.e. servo pulse stream shuts down when logic blocks not active etc.

No reason why PWM can not be done from GPIO header direct either

Look forward to this

~ Andrew


#13

We’re finishing up first round of testing now :slight_smile:

Would like to make it publicly available by end of next month!

-B


#14

GREAT :slight_smile:Look forward to this as I have used dual servo mechanism you can get like this $7 one with scratch and python to Great effect in conference and ‘Shed Talk’ demo’s


This only needs a few jumpers and careful use of the Pi +5 volt rail direct. I would recommend use a separate x AA bat pack for the servo power and just bring out the Pi -ve and pulse pins. Otherwise it is just simple direct connect :slight_smile:
~ Andrew


#15

hi ADAM. could you please tell me how can i control multiple 9g servo by using arduino code. I mean i have tried a lot but that code doesn’t really work fine with multiple servo . It’s fine with single servo. it will be great help if you can send me an email.

my email adress :
prince.towfique29@gmail.com

Thanks.