Software - Tuning

• 01. Software - Tuning
  After the camera is balanced on the Gremsy, it’s time to fine tune some parameters for best performance.

   
• 02. Stiffness Tuning
  Stiffness setting has a significant impact on the performance of the S1. This setting adjusts the degrees to which the gimbal tries to correct for unwanted camera movement and hold the camera stable. The higher you can run the setting without vibration or oscillation, the better.

   

   

  General Method

  Start with a low value of 20 for all axes then turn motors ON. Slowly increase this setting until you feel an oscillation in each axis, then reduce it until the oscillation subsides. You can touch the camera to feel the oscillation during tuning. Increase the stiffness setting 5-10 points at a time until oscillation appears then reduce 5 points until oscillation subsides.

  

   

   

  Step 01 - Tilt Stiffness

  Slowly increase this setting until you feel an oscillation in the tilt axis, then reduce the setting until the oscillation subsides. Make sure there is no vibration when tilting the camera up and down and when moving the gimbal in any orientation.

   

   

  Step 02 - Roll Stiffness

  Slowly increase this setting until you feel an oscillation in the roll axis, then reduce the setting until the oscillation subsides. Pick the S1 up and make sure there is no vibration when you move the gimbal around.

   

   

  Step 03 - Pan Stiffness

  Slowly increase this setting until you feel an oscillation in the pan axis, then reduce the setting until the oscillation subsides. Tilt the S1 about 20 degrees from the verticality and make sure that no vibrations are presented.

   

   

   
• 03. Filter

  The purpose of the filters is to eliminate noise and vibration due to structural resonances in the camera, lens, or gimbal.

  Setting the filters too high or too low can cause signal disturbances that can reduce the overall stabilization.

   

   

  Gyro Filter

  Defines the strength of the filter applied to Gyro sensor output. If the gimbal has oscillations that cannot be corrected by adjusting stiffness settings, the Gyro Filter is used to further tune the gimbal and remove the oscillation.

   

   

  Output Filter

  Defines the strength of the filter applied to motors output. If the gimbal has oscillations that cannot be corrected by adjusting stiffness settings, the Output Filter is used to further tune the gimbal and remove the oscillation.

  1. If the gimbal is vibrating at a high frequency after tuning, increase the filter values.

  2. If the gimbal is oscillating or rocking at a low frequency after tuning, decrease the filter values.

   

   

  Default Values

  Gyro Filter	1
  Output Filter	2

   

   
• 04. Expert / Advanced Settings

  There are some expert parameters that normally do not need to be adjusted. Leave these parameters at default settings unless they are required for troubleshooting.

   

   

  Hold Strength

  If “Auto power adjustment” is enabled, “Hold strength” will be the minimum power level required for the corresponding axis. The controller will automatically adjust power level from minimum to maximum level depending on the displacement between current angle and commanded angle.

  If “Auto power adjustment” is not selected “Hold strength” will be constant power level provided to the corresponding axis and should be adjusted manually. This option is only recommended for advanced users.

  

  For heavy cameras, it’s suggested to increase hold strength for each axis around 10% than the default value. If “Auto power adjustment” is not selected “Hold strength” will be fixed power level provided to the corresponding axis and should be adjusted manually. This option is only recommended for advanced users.

   

   

   

  Gain

  Defines how fast each axis will return to commanded position. To reload default expert settings just press “Default” in the expert menu.

  

   

   

  Default Settings

  HOLD STRENGTH	TILT	ROLL	PAN
  	30	30	30
  GAIN	120
  AUTO POWER ADJUSTMENT: ENABLED

   

   

   
• 05. Follow Mode Settings

  The most widely used mode of single operation is Follow mode where the gimbal operator controls to pan and tilt of the camera. The camera movement will mimic the user’s input from the top-mount while the footage remains stable. The follow mode can be configured to be either very linear robotic, or smooth and cinematic.

  Follow mode settings is available for Tilt axis and Pan axis.

   

   

  Speed

  Defines how fast camera will follow the movement.

   

  Smooth

  Smooth out the camera movement by adjusting this parameter. The higher the value is the smoother camera moves but at the expense of more delay in following the movements.

   

  Window

  When the movement is out of the window zone, the camera starts to move.
  Within the window zone, the camera maintains its direction.

   

  Tilt Lock

  If this option is selected, the tilt axis will maintain its angle and only be controlled by remote control.

   

  AIRBORNE

  This feature is not available on the S1.

  

   

   

   
• 06. Rotation Limit
  Travel of Tilt and Roll axis can be limited using UP LIMIT and DOWN LIMIT. The Pan axis keeps the ability to pan 360 degrees itself.

  

   

   

  UP LIMIT

  Set the up limit for Tilt or Roll axis (in 1 degree unit). The default values are -90 for Tilt and -45 for Roll.

   

   

  DOWN LIMIT

  Set the down limit for Tilt or Roll axis (in 1 degree unit). The default values are 90 for Tilt and 45 for Roll.

   

   

  ROLL OFFSET

  Set the Roll offset (in 0.1 degree unit) is only applicable when there is no remote control signal from remote control will override the roll angle. This is useful to fine trim the horizon. The default value is 0.

   

   
• 07. IMU Sensor

  The IMU sensor used in the S1 is a combination of a high precision 3 axis gyroscope sensor and a 3 axis accelerometer sensor.

  IMU board is enclosed in a weatherproof case and being heated where the temperature inside is controlled around 50°C with 0.2°C accuracy. Thanks to this feature, gyro calibration is no longer required in most situations.

  In order to provide extra high precision data output, the IMU is performed 6-point calibration at Gremsy factory.

  

  The S1 controller has a special algorithm to provide attitude estimation based on input data from the IMU sensor. This attitude estimation helps the controller to command motor output to compensate for camera movement.

   

   

  Gypro Calibration

  Thanks to temperature controlled and heated IMU, gyro calibration is not necessary as the gyro was calibrated at the factory and the temperature inside IMU remains constant around 50 degrees. However, if you notice drift during operation in extreme weather (below -20C or above 50C) please re-calibrate the gyro.

  CALIB AT STARTUP: this feature is not available on the GREMSY S1

  

  After Gyro Calibration, Gyro Offset X, Y, Z will change to a new value depending on the temperature.

  

   

   

  Accelerometter Calibration

  

  Do not use this function, please contact Gremsy Support Engineers. Accelerometer sensor was calibrated properly at the factory to achieve accurate horizon level with special and precise equipment. Users do not need to do this unless it’s required for troubleshooting.

   

  

   

   

   
• 08. Canlink Configuration
  INTRODUCTION

  CANLINK is Gremsy’s proprietary solution to get information from the third party flight controller to correct horizon drift.

  

  Without CANLINK, our gimbal can maintain locked horizon most of the cases where prolonged acceleration is not presented. When prolonged acceleration is presented such as circular flight or prolonged bank turn (where centrifugal force appears), the horizon will drift after a certain period of time.

  

  In order to have Canlink worked properly, GPS module should installed together with flight controller

   

   

  CANLINK CONNECTION

  DJI FC

  Connect the cable from CAN port on hyper quick release to CAN port on COMPASS/GPS module on DJI FC.

  PIXHAWK

  Connect the cable from COM2 port on hyper quick release to TELEMETRY 1/ TELEMETRY 2 on Pixhawk , Pixhawk 2. Once connected, the gimbal controller will automatically send MAVLINK message to set attitude update rate of flight controller at 10Hz.

  

  Baudrate on Pixhawk should be set at 57600bps, 8 data bits, No Parity, 1 Stop bit (8N1).

   

   

  USING CANLINK

  When the first turn on the motor, make sure the pan axis is aligned with the forward direction of the copter in order for the gimbal to calculate the attitude correctly. After turning on the motor, the LED status turns to the pink color indicating that CANLINK connection between gimbal and flight controller has been established.

   

   

  FINE TRIM THE HORIZON

  There is tolerance between the gimbal’s IMU and flight controller’s IMU due to mechanical mountings error or calibration error, for example, the gimbal’s frame and the flight controller’ plane is not perfectly parallel with roll and pitch axis and usually within 1-2 degree. To address this, we offer a way to fine trim the horizon in 3 steps.

   

   

  STEP 1:

  TURN MOTOR ON for the first time, make sure the pan axis is aligned with the forward direction of the copter during turning on the motor. LED status will change to pink color.

  

   

   

  STEP 2:

  Use radio control to move the pan to a position which is 180 degree away from the forward position of the copter. Use a bubble level in order to observe the horizon: adjust roll offset until it is level.

  

  If radio control is not available, switch gimbal in lock mode and rotate the copter 180 degrees could achieve the same result.

  

   

   

  STEP 3:

  Use radio control to move the pan to a position which is 90 degree away from the forward direction of the copter. Use a bubble level in order to observe the horizon: adjust tilt offset until it is level.

  

  If radio control is not available, switch gimbal in lock mode and rotate the copter 90 degrees could achieve the same result.