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How to control two servos with one joystick

#1

I actually have two sets of three servos that I want to control with one joystick. Pan/Tilt/Zoom control on two cameras – one joystick.
I have a mini-maestro 18 and 6 servos. Hopefully this one controller can do the job.
Three questions:
I’ve been able to use the control software but need joystick - examples somewhere already?
Two sets of servos, one joystick ?
Saving settings for recall. For example point “location-1” and save it. Point “location-2” and save that. Recall (somehow) “location-1” and move the servo(s) to that position. Recall “location-2” and move to that position.
Thanks in advance for your help.

#2

Hello.

There are probably several ways you could accomplish something like that. Could you be more specific about what you are trying to do? Do you want to use the Maestro as a standalone controller for your system, or are you controlling it from a computer or separate microcontroller? What kind of joystick are you trying to use? How do you want the joystick position to relate to the target locations you described?

Brandon

#3

Thanks for the reply. I’m working swing shift and will have a break later. Back auto then.

#4

Thanks for your prompt response.

In the past I did this with the Pololu Minimaestro but I am attempting to run audio, stream live and manage two cameras while talking to a person on a third camera and finding the right slider and sliding it requires
too much attention, too much time, while an event is in live mode.

My application is controlling two p/t/z cameras from a single joystick via cat-5 cable.

I was using two laptops for this process but that is not required. I leave the hardware options open because I just don’t know what is possible/reasonable on this score.

I need to have the joystick in the “studio” portion of my system and run 100’ of cat-five to the “pod” portion of my system. At the pod the one cat-5 needs to split to two 100’ sections of cat-5 leading to each
of the cameras. This allows me to locate the cameras in the venue being recorded/streamed and my studio to be located in an adjacent room. This allows me to I can talk to a person holding a third camera as well as monitoring the actual recorded audio from
a room physically removed from the venue.

It would be fine to have a controller/raspberry PI/something linked to the joystick with the cat-5 cable carrying the control signals for both cameras to a board that would split the one cat-5 into two cat-5’s.
Then the laptop(s) would be free for the other things they are doing. There is a laptop at each location and they could be utilized in any way that would be useful.

The joystick I have is an industrial-grade unit from XXYYY and it would be great to use it – but not mandatory. It has the left/right, up/down, twist and a push-button on top as well as four buttons on it’s base.
I’m away from the studio and don’t have the specifics on that joystick but will include a link to the mfg on Monday.

Functionally, I would like to have the control available from the MiniMaestro: home, plus and minus range limit & speed.

My portable streaming studio has been in storage for three years but I have a possible streaming project for June 21 – 20 days out – and it would really improve my operations to have this functionality completed
in time to work with it some before that time. Is it possible that you could refer me to someone who has done this before, that would accept a reasonable payment for creating the solution?

A desirable enhancement would be to be able to record setpoints which would include the values for X, Y and Z as well as speed for each so that preset scenes could be created. Then selecting from a few standard
scenes would be a one-touch process.

Thanks in advance for your assistance.

Herschel Mobley

#5

Your system sounds more complicated than just controlling some servos from a Maestro, and we can only offer help with the use and implementation of our products. If your joystick can output raw signals to the Maestro (e.g. an analog voltage that ranges from 0-5V for each axis and digital 5V or ground signals for each button), you should be able to read each of those signals with a dedicated Maestro channel and write a Maestro script to use them to control your servos. However, if it uses some protocol that needs additional decoding, it might not be practical to read them directly from the Maestro. If you are not sure what kind of output the joystick has, and you have a link to your joystick’s specifications (such as a datasheet or product page), I’d be glad to look into it more for you.

As I mentioned, you would need to write your own software for controlling the servos the way you are describing. You are welcome to post here on our forum to see if any of our other members would be able to help you, but we do not have any specific referrals.

Brandon

#6

Hi - yes, complex seems to be my middle name! I’d appreciate knowing if I could link the joystick directly to the servos via th Moni Maestro. The joystick is:

AXIS T8311, part no 5020-101, fromAxis Communications, Lund, Sweden.

Then, it’s time to visit the forum.

Blessings to you, Herschel

#7

From a brief Internet search, it looks like that joystick uses a USB interface and does not give access to the raw output signals, so you would not be able to connect it directly to the Maestro (the Maestro cannot act as a host device).

You could write your own program to process the joystick inputs with a computer and send commands to the Maestro through USB (either using the virtual COM port or its native USB interface). We do not have any examples for doing that particular application, but you might find the “Writing PC Software to Control the Maestro” section of the Maestro User’s Guide helpful as a starting point.

Brandon

#8

Thanks for the advice. While talking to you I found a software engineer at work to help me. I will forward this info to him. It will cost a bit but finished = good!

I really appreciate the support and will undoubtedly be looking to Pololu for hardware in the future.

Blessings to you, Herschel

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