ArduCopter SHOW parameters

The custom ArduCopter firmware we provide with Skybrush Live has a new SHOW flight mode and a corresponding new parameter group (SHOW_*), containing parameters that change drone behaviour related to the SHOW flight mode. Details of SHOW parameters are provided below.

SHOW_CTRL_MODE: Flags to configure the show position control algorithm

This parameter is for advanced users

Controls various aspects of the position control algorithm built into the firmware

Bit Meaning

0

Velocity control

1

Acceleration control

Value Meaning

0

Position control only

1

Position and velocity control

3

Position/velocity/acceleration control

SHOW_CTRL_RATE: Target update rate

This parameter is for advanced users

Update rate of the target position and velocity during the show

Range Increment Units

1–50

1

Hz

SHOW_GROUP: Show group index

Index of the group that this drone belongs to

Range Increment

0–7

1

SHOW_HFENCE_DIST: Hard fence minimum distance

Minimum distance that the hard fence extends beyond the standard geofence

Range Increment Units

1–1000

None

m

SHOW_HFENCE_TO: Hard fence timeout

Minimum time that the vehicle needs to spend outside the hard geofence to trigger a motor shutdown

Range Increment Units

0–120

None

sec

SHOW_HFENCE_EN: Hard fence enable/disable

Allows you to enable (1) or disable (0) the hard fence functionality

Value Meaning

0

Disabled

1

Enabled

This parameter is for advanced users

PWM channel to use for the LED output (1-based) if the LED type is "NeoPixel", "ProfiLED" or "NeoPixel RGBW"; the MAVLink channel to use if the LED type is "MAVLink"; the I2C address of the LED if the LED type is "I2C"; the UART index if the LED type is "WGDrones". For UART-driven LEDs, you also need to set the baud rate in SERIALx_BAUD and set SERIALx_PROTOCOL to "Scripting" to ensure that the UART is initialized.

SHOW_LED0_COUNT: Number of individual LEDs on a LED channel

This parameter is for advanced users

For NeoPixel or ProfiLED LED strips: specifies how many LEDs there are on the strip. For I2C LEDs: specifies the index of the bus that the LED is attached to.

SHOW_LED0_GAMMA: Gamma correction factor for the LED channel

This parameter is for advanced users

Specifies the exponent of the gamma correction to apply on the RGB values of this channel. Set this to 1 if you do not want to use gamma correction or if the LEDs perform gamma correction on their own; otherwise typical values are in the range 2.2 to 2.8 for LEDs. Set a value that provides an approximately linear perceived brightness response when the LEDs are faded from full black to full white.

Range Increment

1–5

0.1

SHOW_LED0_TYPE: Assignment of LED channel 0 to a LED output type

This parameter is for advanced users

Specifies where the output of the main LED light track of the show should be sent

Value Meaning

0

Off

1

MAVLink

2

NeoPixel

3

ProfiLED

4

Debug

5

SITL

6

Servo

7

I2C RGB

8

Inverted servo

9

UART (WGDrones)

10

NeoPixel RGBW

11

I2C RGBW

12

Notification LED

SHOW_LED0_WTEMP: Color temperature of the white LED of the channel

This parameter is for advanced users

Specifies the color temperature of the white LED of the channel if the channel makes use of an additional white LED. Set to zero if you don’t know the color temperature of the white LED or if there is no white LED.

Range Increment

0–15000

100

SHOW_MAX_XY_ERR: Maximum placement error in XY direction

Maximum placement error that we tolerate before takeoff, in meters. Zero to turn off XY placement accuracy checks.

Range Increment Units

0–20

0.1

m

SHOW_MODE_BOOT: Conditions for entering show mode

Bitfield that specifies when the drone should switch to show mode automatically

Bit Meaning

0

At boot

1

When authorized

Value Meaning

0

Never

1

At boot

2

When authorized

3

At boot and when authorized

SHOW_ORIENTATION: Show orientation

Orientation of the X axis of the show coordinate system in CW direction relative to North, -1 if unset

Range Increment Units

-1–360

1

degrees

SHOW_ORIGIN_AMSL: Show origin (altitude)

AMSL altitude of the origin of the drone show coordinate system, -10000000 or smaller if unset

Range Increment Units

-10000000–10000000

1

mm

SHOW_ORIGIN_LAT: Show origin (latitude)

Latitude of the origin of the drone show coordinate system, zero if unset

Range Increment Units

-900000000–900000000

1

1e-7 degrees

SHOW_ORIGIN_LNG: Show origin (longitude)

Longitude of the origin of the drone show coordinate system, zero if unset

Range Increment Units

-1800000000–1800000000

1

1e-7 degrees

Controls the brightness of light signals on the drone that are used to report status information when the drone is on the ground

Range Increment

0–3

1

SHOW_START_AUTH: Authorization to start

Whether the drone is authorized to start the show

This parameter is volatile; it is reset to its default after every boot
Range Increment

0–1

1

SHOW_START_TIME: Start time

Start time of drone show as a GPS time of week timestamp (sec), negative if unset

This parameter is volatile; it is reset to its default after every boot
Range Increment Units

-1–604799

1

sec

SHOW_SYNC_MODE: Time synchronization mode

This parameter is for advanced users

Time synchronization mode to use when starting the show

Changing this parameter requires reboot
Value Meaning

0

Countdown

1

GPS time

SHOW_TAKEOFF_ALT: Takeoff altitude

This parameter is for advanced users

Altitude above current position to take off to when starting the show

Changing this parameter requires reboot
Range Increment Units

0–5

0.1

m

SHOW_VEL_FF_GAIN: Velocity feed-forward gain

This parameter is for advanced users

Multiplier used when mixing the desired velocity of the drone into the velocity target of the position controller. Lower values will result in more relaxed/stable behaviour, at the price of a smoothed trajectory with rounded corners, less accuracy and more lag behind desired position. Higher values will decrease lag, make trajectory following more accurate, sharp and agressive, but might increase overshoot at corners and decrease stability if general attitude control is not tuned well.

Range Increment

0–1

0.1