Header pins 1-8
Bidirectional PWM (Input / Output)
Battery positive terminal
Battery negative terminal
Motor #3 (YAW)
Motor #2 (ROLL)
Motor #1 (PITCH)
Spektrum Satellite Receiver #2
IMU Port #2
IMU Port #1
Spektrum Satellite Receiver #1
|IMU mounting hardware||x1|
|IMU mounting hardware||x1|
Before mounting, you may want to solder the battery terminals (Centerpiece, Centerpiece HV) and the motor wires (Centerpiece HV only)
Never mount the IMU using tape. Always use the supplied bolts.
Always use all provided four bolts to mount the IMU.
The IMU cable is made of ultra-flexible silicon wire which has delicate isolation. Make sure it’s not chafing against any sharp edges of the gimbal.
Never mount the IMU without using a spacer as it has components on both sides.
If using two IMUs, run Autotune for the first time with just the camera IMU connected.
Turn off all power to both the R/C and the Centerpiece while connecting.
The yellow wire (signal) on the connectors must face up.
Make sure you don’t misalign the R/C connectors (connecting only one or two pins out of the three), as this may cause damage to both the Centerpiece and your receiver. Inspect the connections, and only then reapply power to the system.
S-Bus receivers may only be connected to the SBUS_IN port.
PWM receivers may be connected to any of the first 4 PWM ports.
Please refer to the diagrams in Product Overview.
It is sufficient to connect Singal and Ground.
The Centerpiece is a high precision, sensitive controller. To realize the full potential of the controller, your gimbal mechanics must be up to the task. Please take special care in following the listed steps.
Take special care to ensure the camera is balanced on all three axes.
Check the damping setup for play.
From our experience, the Centerpiece prefers harder damping as this provides a more stable platform for the gimbal to work against. We generally advise against using multiple damping layers or soft damping, although this can vary between gimbals.
Make sure your damping setup can not easily “bottom out”, causing contact between hard surfaces, under loads, which will translate to violent shakes in the video under high accelerative loads.
Please follow the instructions at http://phobotic.com/start
Once the application is installed, it can be launched from the Chrome Apps Launcher which appears on the taskbar or in Chrome’s bookmarks bar.
If you can’t find the launcher, please follow the following steps:
For the software to work, an IMU has to be connected to the Centerpiece.
You must have an internet connection the first time you connect a Centerpiece to your computer in order for the drivers to be installed.
After connecting the device, please wait 10-15 seconds before connecting the application
When the application is started, you’ll be presented with a list of available serial devices to choose from. If you are not sure which port is correct, you can just try them out one by one (once you see an error message, go to the next).
Alternatively, you can connect the Centerpiece after launching the application, and see which device is added after pressing Refresh (it will take a few seconds to show up, and it is required to wait 6-8 seconds after the device appears before connecting).
Before you start, please follow the “Gimbal Setup” section closely. Any deficiencies in the construction of the gimbal will interfere with the correct operation of the autotuning process.
Make sure the gimbal is free to move at least 30° in all directions.
For tuning of an aerial gimbal, the gimbal has to be mounted on the multirotor, with the multirotor resting firmly on a flat floor.
For tuning of handheld gimbals, the gimbal has to be held by a rigid clamp. We advise to use a bicycle mechanic stand (such as the Park Tools PCS-9) to hold your gimbal securely. Many of these mounts have no trouble clamping the 25mm Carbon tubes used in many handheld gimbals. The heavier the stand is, the better the autotuning will perform.
Do not simply rest the gimbal on anything while autotuning. The gimbal has to be mounted or clamped to a solid object
Any slop in the mounting of the gimbal will adversely affect autotuning results
During the autotune process, the camera may violently jerk in various directions. If your gimbal configuration is one that allows the lens or camera to contact parts of the gimbal or frame, please pay attention to the autotune process and manually prevent the camera from hitting any hard parts.
On startup, please wait until hearing a beep before starting Autotune
The autotuning function can be started in two ways:
On startup, please wait until hearing a beep before starting Autotune.
It is normal for the the camera to momentarily vibrate during autotuning.
Power climbs to > 80 and Autotune fails
Power > 50 or motors getting very hot
Usually indicates that the motors are too small for the payload.
Gains too low (< 100K)
Note that this is possibly a valid result on a small gimbal with low pole-count motors. Always test the gimbal before making changes.
Gains too high (> 2M)
Note that this is possibly a valid result on a very high pole-count motor (> 28 poles).
Vibrations after Autotune
See Overdamped Axis.
Vibrations at specific angles
Instructions for the application are embedded in the application itself. Detailed instructions as well as explanations of the various parameters in each section of the application are accessible by clicking the button.
In case you need assistance with the tuning or operation of your Centerpiece controller, please send us a support request through the application by pressing the “Send support request” button. You are also invited to use the Technical Support section of our forums at http://forums.phobotic.com.
The startup procedure should be performed with the gimbal as upright as possible. On an aerial platform, the multirotor should be on level ground.
Do not move the gimbal until initialization is complete.
In High Performance stabilization mode, the gimbal is fully operational. When entering this mode, Blue LED 5 will turn on and the Centerpiece will beep.
Any interference with the gimbal (such as manually moving the camera by hand, resisting the gimbal) will cause the Centerpiece to change into Stabilization Recovery mode.
Stabilization Recovery mode allows the user to manually alter the position of the camera on the yaw axis and the pitch axis. When interrupted or manually moved, the gimbal will not attempt to return to the home position, but instead enter this mode.
When entering this mode, Orange LED 5 will turn on and the Centerpiece will beep.
To exit recovery mode, place the gimbal in an upright position and simply let go of the camera and allow the gimbal to assume stabilization. After several seconds without interference, the gimbal will try to home again into the new position on yaw and pitch, while leveling the roll.
Under normal operation, as long as the gimbal is unperturbed, the gimbal is not supposed to enter Recovery mode. If your gimbal often enters Recovery mode on its own, it is most likely a sign that one or more of the axes are mistuned. Please consult the Performance Tuning chapter, or submit a support request through the application.
If the battery goes below a set cell voltage, the Centerpiece goes into LVC mode, immediately stopping the motors to prevent any damage to the battery.
The only way to get out of LVC mode is by changing the battery and starting the Centerpiece again.
If the Centerpiece is connected by both USB and battery, and the battery is removed, the Centerpiece will enter LVC mode.
The Centerpiece and the Centerpiece HV have 5 LEDs. Each LED can have one of the following states:
|IMU heating up|
Software update in progress
(every LED represents 20% progress)
When the gimbal is operational, LEDs 1-3 display the battery status as follows:
|Battery is almost empty|
LED 5 displays the stabilization mode:
|High Performance mode|
|Starting up or update in progress|
|Calibration in progress|
|Entered High Performance stabilization mode|
|Entered Recovery stabilization mode|
|Gimbal is off|
|Autotune finished successfully|
|Detected motor direction change|
A firmware update can be done in two ways: using the application, or by starting the Centerpiece in USB Drive mode and directly copying the firmware file to it.
Using the application
Using USB Drive mode
After either of these processes are performed, the Centerpiece will
Do not unplug the Centerpiece while an update is in process (until Blue LED 1 is on again).
In most installations, there would be a slight static horizon error, which can be caused by a mounting error of either the camera or the IMU. This error is very simple to fix:
The user gain parameter provides a way to fine-tune the results of the autotune process. Increasing the user gain will make the stabilization more aggressive. Reducing it may help reduce vibrations.
The user gain parameter is accessible in the application dashboard as well as in the setup menu.
When follow mode is enabled for an axis, that axis will follow movements of the frame. The Centerpiece allows turning Follow on or off separately for each axis.
Follow mode is enabled by default on the Yaw axis after Autotune has been performed.
In order to modify the follow mode behavior for an axis:
The Centerpiece can hold up to 5 Follow mode configurable behaviors for each axis, called Follow Profiles. The current profile can be changed from a drop-down in the application, or edited by clicking Edit.
The Follow mode behavior can be configured manually by setting the individual parameters, or automatically by choosing a configuration preset from a list.
For more information, see the instructions inside the application ().
R/C can be set up using the application.
The Centerpiece holds a list of 15 R/C channels. Each channel can be attached to a physical R/C control, and assigned a function.
To set up a new R/C control:
A description of the available R/C functions follows.
The Position function controls the position of the axis. There are two modes of position control:
Speed mode - the R/C controls the speed of the axis. The camera moves as long as the stick is not at center.
Angle mode - the R/C controls the absolute position of the axis. As long as the axis is held in place, the camera doesn’t move.
By default, position control operates in Speed mode. To switch to Angle mode, select “Angle” from the Mode dropdown.
The max. travel of the axis under R/C control can be limited by enabling the Position limiter in the R/C settings screen. The allowed position range is displayed graphically on a circle:
The orange-filled arc marks the allowed positions of the axis. A black dot shows the current position of the axis, so you can move the camera in real-time and see how its position is reflected on the circle. Note that the Centerpiece has no sense of direction: “up” and “down” on the circle might be the reverse of what you’d expect, so using the black dot to understand this representation is recommended.
The recommended way to set the endpoints is as follows:
The Follow function controls the Follow speed of the axis. It can also be used to turn Follow off and back on.
When the Follow function is selected, the R/C settings panel shows the current follow rigidity value. To get a meaningful follow behavior, click the Setup button and follow the instructions. You can move the R/C control around to see how it is interpreted. The higher the rigidity, the faster the follow.
You can also modify the travel parameter to make the follow control softer / more aggressive.
R/C Follow control can also be used to reset the position of an axis using the R/C. This can be configured as follows:
Moving the axis using the R/C while Follow mode is enabled will move its “home” position.
Configuration banks provide the option to store several sets of the Centerpiece configuration on the device itself. The Centerpiece allows for up to 5 banks to be configured.
When modifying the Centerpiece parameters, only the active bank will be modified. To configure another bank, you must switch to it first.
The current bank can be switched from the application’s dashboard, or using the on-board buttons (see here for instructions).
When switching to another bank, the Centerpiece will reboot.
In the application, you can also save/load the current bank from a file, reset a bank to factory defaults, and copy the configuration from one bank to another.
It is often easier to copy a working bank to an unused one using the application, and only then tweak the latter, instead of starting from a clean bank.
Always start with an Autotune (gains and power). Tuning manually from zero is not advised.
Always test your gimbal before attempting manual tuning. It is advised to back up your configuration before making changes (see Configuration Banks).
Also keep in mind that low gains (< 100K) could also indicate mechanical problems, which cannot be solved by manual tuning.
The Gimbal Analyzer section in the application is a tool for running performance tests on the gimbal and inspecting their results. The tests are performed by injecting an artificial disturbance (“impact”) and measuring how well the gimbal corrects the error. Specific explanations of the different options and parameters of the Analyzer are available in the in-app help.
Here’s an example of an Analyzer graph.
Impact graphs often have these parts:
The following image shows a graph of the same axis, this time with no initial impact. This is just a recording of the position error during stabilization. When looking at Analyzer graphs, always pay attention to the y-axis scale. In the following graph, the error range is -0.002° to 0.003°.
This section shows a few of the common problems that can be detected using the Gimbal Analyzer.
The following graph shows a well-tuned axis. The following characterstics make it a good graph:
Some amount of overshoot should be expected in a well-tuned axis.
An underdamped axis is often characterized by a low-frequency (< 100 Hz), long ringing phase. This can be seen in the following impact graph, and its FFT.
Note that in some case, such graphs indicate flex in the gimbal. One particular case, where this problem appears on the yaw axis, is caused by dampers that are too soft.
An overdamped axis is often characterized by a high-frequency (> 100 Hz), high amplitude, short-duration ringing phase. This can be seen in the following impact graph, and its FFT.
In most cases this level of vibrations means that the Centerpiece can’t control the axis due to incorrect settings or a mechanical problem. Usually these vibrations will be audible.
This is an extreme case of an overdamped axis, and should be handled the same.
In the following graph you can see that the axis is properly restrained, but the absolute error never actually reaches zero.
Vibrations during R/C movement of the Pitch axis are caused by the lens mass becoming perpendicular to the roll axis (instead of axial), changing the moment of inertia of the camera about the roll axis. The yaw is also affected, but to a lesser extent.
A static horizon error, where the horizon is constantly off by a few degrees in a certain direction, is usually caused by small mounting errors. To fix this, please follow the procedure in Static Leveling.
Horizon that is visibly shifting during a simple hover and staying shifted (usually seen immediately after take-off) indicates that the IMU is experiencing severe vibrations. This would be accompanied by an unstable image showing shaking and/or vibrations. It’s important to understand that the horizon problem seen in this case is a symptom of stabilization problems, either mechanical or tuning-related. This is not a problem in itself. The only way to solve this condition is to troubleshoot the stabilization of the gimbal.
|Board not starting (no lights)||Board not powered|
|IMU not getting up to temperature (Orange LEDs flashing for over 30 seconds)||
Environment too cold
IMU might be damaged
Gimbal drifting on startup
Gimbal moving around violently on startup
|Gimbal moved before entering High Performance mode|
User gains should be lowered
Loose rigid wires or slop in gimbal parts
|Autotuning does not end||Please submit a support request|
|Gimbal enters Recovery mode on its own during stabilization||
Some axis is not properly tuned.
Consult the Performance Tuning section or submit a support request
|Centerpiece is not entering High Performance mode, or repeatedly enters Recovery mode on its own||The Centerpiece is mistuned.|
|Gimbal doesn’t start and LEDs show||IMU not detected. Faulty cable / IMU.|
|IMU LED not purple after start||IMU problem.|