I am looking for any information if a brush-less gimbal can be controlled via the APM boards gimbal controller and how to set this up.
Currently my Brush-less gimbal has its own stand alone gimbal controller, but I would prefer to reduce the hardware and remove this item if this can all be done via the APMs gimbal controller.
If any one has this working can they please advise in detail how they have this set up?
I suspect it cant be done without the separate controller as yet because of the power supply and control management to the motors is not available?
But just on the off change I thought to ask just in case some one does have it working.
Thanks in advance , John
Replies
you could try this.
set gains for stabilization like(PID) to zero. but leave all the setting for RC as is, this way gimbal controller IMU won't do anything, connecting APM cam controller will control the gimbal now.
But I am looking for way to disable cam stabilization altogether in flight, sometime I like to just point camera where I want to pointed, like when you banking stabilization pointing camera opposit direction to where my flight path is, when i just fly around i like to fix my camera to one point.
Someone please correct me if I'm wrong, but it seems to me that the hardware is there; couldn't we use re-flashed escs to drive the motors and I2C to get the sensor data ? Only thing missing is the ESC firmware and APM code to drive them via PWM outputs. No idea if APM has the dsp needed to handle an extra sensor on I2C bus, but should be doable on pixhawk.
www.baskindustries.com.au
No, AP can't control a brushless gimbal directly. Here's why. The AP controler has the IMU on the airframe and sends servo pulses calibrated to degrees. With a BG there is no feedback like a servo pot. The BGC doesn't know the angle of the motors,, but it does know the earth frame rotation of the gimbal IMU. That's its feed back.
Bottom line is it isn't in there code yet, but it can be with out to much trouble. Just send pitch control thru the AP, you don't need roll control(unless you want tilted video), and yaw control will have to be the copters yaw, unless you have a 3 axis gimbal.
I suppose I will work on that, I just need to get a BG system to test on. btw for full disclosure(and bragging rights) my name is on the authors list of plane an copter for my efforts on the gimbal stabilization math. I know how to control a gimbal ;)
Any updates on this project?
It is unlikely that the APM will be used to directly control Brushless Gimbal mounts without a controller for 2 reasons.
As John says above, additional electronic control and driver circuitry is required to to drive brushless gimbals, circuitry that is not present on any of the flight controllers.
The other reason is that existing brushless gimbal controllers really consist of 2 parts, the control board and the on camera gyro sensor board.
The sensor board means that the controller only has to compensate for the camera not being level to stabilize the camera.
This is much quicker and smoother than using a controller to compensate for airframe movement with variable effect servo arms.
If independent pitch control is desired it is a simple matter to feed in an offset to the gyro.
Basically you will probably always need a separate control board (pair).
Eventually for auto pointing the pitch (and eventually yaw) functions of the APM may provide auto control of the pointing override function to the Gimbal controllers.
Someday, somebody may build a flight control board with built in controls for and gyro slave board for a brushless gimbal, but what we have now isn't it.
Where as the brush-less motors would require a type of power management controller for managing the power to each three motor wires much the same as a ESC does. This is why I doubt it is possible with the current AMP boards, but you never really know unless you ask the question right. Someone may have nutted it out!
I have the APM 2.6 running fine, and want to add a stabilized gimbal for a Hero camera.
Most folks seem to be bolting on an autonomous gimbal, like the Tarot, but then I see references in the APM setup for controlling the gimbal stabilization.
Is this APM control intended for stabilization, or is it just to send directives to the independent gimbal board as servo (angle) inputs?
Cheers.