Hi guys, I did some research and found out that arduino can only control 12 servos, and for my computing project I need to be able to control 17 servos. I found this shield http://www.ebay.co.uk/itm/Arduino-Sensor-Shield-digital-analog-module-servos-V4-/320750351268?pt=UK_ToysGames_RadioControlled_JN&hash=item4aae35f3a4 but I'm not sure if it's any good. Can you please give me some advise on what shield to buy that is avaible in UK?
Thanks in advance
Hi,
That sheild only contains connections, it does not appear to contain any active components and so does not expand the capabilities of the Arduino.
You could use two Arduinos with one managing a small number of servos and doing most of the processing, the second is driving the remaining servos based on commands from the first.
Its a cheap enough solution if you build your own Arduinos.
Duane B
Besides multiple Arduinos, you might want to look around at sites that specialize in robots. There they generally have platforms that are controlled by USB and serial ports to control a larger number of servos. For example, there is the Pololu board that can control up to 24 servos from one board: http://www.pololu.com/catalog/product/1356. They have a cheaper board that supports up to 18 servos, but it may make sense to go with the larger board, in case you ever need to add more servos in the future. It looks like they have a few distributors in the UK, so you might check at those locations first: Pololu - Distributors. Note, I've bought wires and such from Pololu, but I haven't bought boards and shields.
Because this board it targeted towards servos, it solves the other problem that you likely would run into with the Sensor Shield, and that is it is probably not a good idea to run multiple servos off of the internal Arduino power supply. If you do go with multiple power supplies, remember to connect the ground wires of all supplies (this board may do that, I don't know).
Another option if you were going the multiple Arduino route is something like the DFRobot Romeo Romeo - a Robot Control Board with Motor Driver (compatible with Arduino) - DFRobot, which has 14 digital pins, but it has an option that you can run an external power through the pins, to allow you to run 10 or so servos. A lot of shields and boards that I had looked at don't have this external power option.
thanks for the reply! very helpful! I will probably go with http://www.pololu.com/catalog/product/1356, thanks again!
An ssc-32 servo controller made by lynxmotion can control 32 servos and easily works with the arduino (but it is not a shield).