RC servo, automated-repeating servo driving project

Hello,
I need help determining what hardware/software I need for my project using RC servos.
What I want to do is drive a single RC servo with an automated,repeating routine while monitoring and charting servo V,A, & temp.
This routine would simulate RC servo use in an aircraft and would be ‘taught’ to the device utilizing RC control hardware.
If I understand what I’ve gleaned so far, I need…

An Orangutan programmable controller
“Pulse reading code” as ref: from the above quote from the Pololu servo controller forum.
“servo generation” code.
A USB AVR controller programmer.
Various connectors,wiring,power source.

Also, could you refer me to what I need to add the ability to measure/record servo output torque and position (actual servo output shaft position).
Thank you for your assistance.
Jay.
P.S. Any idea why I end up with the words ‘quote’ around my quoted text instead of quotation marks? :confused:
From moderator: you closed your quotes with “/quote]” instead of “[/quote]”. I fixed it for you. -Ben

Hello,
If your goal is to drive a single servo with some kind of a program that also needs to measure incoming R/C pulses and temperature (what are V and A?) I would recommend our Baby Orangutan B-328 or Orangutan SV-328. Use the SV-328 if the size and weight are okay for your application - the LCD is great for debugging and the 5V regulated power should be enough to power your servo from, say, a 7.2V battery.

We will be releasing a new version of the AVR Library this week that will include pulse reading code (actually, it is in the current release of the library, but it is not yet documented, and the new version will have significant improvements.) I am not at all sure what you plan to do with the R/C pulse input, but that library code will probably help you get started.

-Paul

Hello Paul,
Thank you for your reply.
My project is to test RC servos.Torture actually :slight_smile: .
I don’t necessarily need to measure incoming R/C pulses. I want to operate the servos as they would operate installed in a R/C vehicle. From the post I quoted in the Maestro controller forum I got the impression a ‘routine’ could be captured and duplicated by one of your controllers using RC equipment to input the ‘routine’. This would be invaluable for confirming/duplicating results.
Volts, amps,and temperature would be measured as a means to validate the load imposed upon the test subject RC servo and to make comparisons between different RC servos.
The RC servos will be powered by standard RC battery equipment.
Can the Orangutan channels be configured as inputs similar to the Maestro?
I would like to add ‘output shaft location’ and ‘developed torque’ information if I could develop or locate the appropriate sensors.
Again,the RC pulse input will be the means to ‘program’ the controller with a ‘routine’ that would duplicate the operation of a RC servo as used in a RC vehicle (aircraft) so that the controller can then duplicate the programmed routine continuously, looping for several hours.The routine would involve fine and extreme travel motions and can involve dozens of movements.
Thank you for your input.
Jay.

Hello Jay,
Do you have any programming experience? You are talking about a project that would be a significant challenge even for an experienced microcontroller programmer. For example, you will definitely need to save a copy of the R/C signals on your PC so that you can use the same exact test with future revisions of your code, right? Getting the record/playback and the load/save functionality all in there is going to take a lot of work.

Programming the Orangutan is nothing like programming the Maestro, but yes, the channels can be configured as inputs.

-Paul

My programming experience consists of classes in school a long time ago.Thats why the interest in using the RC equipment to establish the routines.Recording/saving the RC signals is essentially what I’m after (Could this be an iPod project :wink: ) along with the ability to view & log data from sensor inputs.
Sounds like the programming for the RC input will be the major hurdle.Would creating the servo routines directly be much simpler? Initially the device programming is what scared me but as I think about it, I could develop simple/discreet routines,based on my objective(position accuracy,speed,etc.) and call them as desired and loop.
Is this level of project better served with a different type of hardware? Do you have other recommendations?
Thanks again for your input.
I really like all the gadgets you guys have.
Skies.
Jay.

Okay, well if I were you I would take it one step at a time. Get an SV-328 + programmer or SVP-324 (no programmer required) and set it up to drive a servo in some pattern. The servo functions in our AVR library make this pretty easy. Next try outputting some simple messages to your PC via the serial port/USB (the AVR programmer can be used as a USB-serial converter). You can use the serial functions that we provide for that, as well. You can then connect a sensor and try sending sensor values to the PC for logging.

Once you get to that point you will have most of what you need. If you get that far, and you want to look into reading R/C pulse inputs, you should be able to understand what will be required.

Good luck!
-Paul