Servo Controller like the HB-25 Motor controller

AndrewParsons

Hello all,

I am looking to connect 6 45 amp ESC Brushles mottor controllers to a servo controller. I will be using a laptop on the surface that will comunicate with the ROV below using RS-485. I have a few HB-25 motor controllers, and they are great, but I need to move to brushless motors since they work much better under water.

So my question is do Servo controllers (when not getting constant guidance from Basic Stamp 2) operate much in the same was as the HB-25 does? Does a servo controller just allow more servos or does it continue the pulse once it has recived one from the micro controller?

HB-25
This module is dependable and highly-compatible with any microcontroller that
can generate a servo compatible pulse. In the simplest sense the HB-25 allows a
DC Motor to be controlled much like a Continuous Rotation Servo. While the
signals are compatible, the HB-25 does not require refreshing as a servo does; a
single pulse can maintain the output.

Thanks in advance

Andrew

Duane Degn

Most, if not all servo controllers don't need continous updates.

Parallax's Servo Controller uses serial communication rather than pulses as input. This lets the master uC control all 16 servos with one pin.

It would be possible to use a Propeller board (QuickStart etc.) to act as a sort of "ServoPAL" that controls 16 servos instead of 2 (of course it could also controll brushless speed controllers). You'd use 16 pins as inputs that listen for pulses and the other 16 pins as outputs to refresh the 16 servos so the master uC wouldn't need to.

I personally think you'd be better off using a serial line to tell the slave controller where you want the servos set. You don't actually need an official Servo Controller board to use the Servo controller firmware (I'm not so sure about the PC software but I bet it would also work with other Propeller boards). You could use a QuickStart board (which costs less than a servo controller board). If you use a Prop board that isn't the official Servo Controller board, you'd need to do some soldering to make all the connections you need. It may well be worth the extra money purchasing a ready made solution such as the Servo Controller.

As I think about it, the Servo Controller looks like a fast and easy way of controlling a bunch of servos.

I've lately had several projects using lots of servos. Here's my 32 servo demo and my attempt at an 18 servo hexapod.

Edit: I just reread your post. Making a 6 servo "ServoPAL" type device from a Propeller board would be really easy.

AndrewParsons

Duane,

Thank you for your promt reponse. I have yet to make the switch over to the Propeller. So just to clarify once i send a varaible down the slave that slave will only need to tell the servo controller once and that countroller will cotinue to pulse X amount until the slave sends another command?

Thank you so much for your help and support.

Andrew