Parameter groups and variables

Index

activeMarker

The Active Marker deck is mainly designed for Qualisys mocap systems and supports Qualisys Active markers, but it can also be used with other systems in a simplified mode. The deck has 4 arms with one IR LED on the tip of each arm and a light sensor in the center of the deck.

The deck is configured using the parameter sub system, for details on which parameter to use, see below.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

amarkUartTest

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

asc37800

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

BigQuadTest

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

colAv

Onboard collision avoidance algorithm.

Buffered Voronoi collision avoidance (BVCA) is a reactive multi-robot collision avoidance method [1]. It is suitable for scenarios with low to medium spatial contention

We obtain the positions of neighbors on the same radio channel from the

BVCA acts by modifying the setpoints sent from the commander to the controller. The new setpoint will be as close as possible to the original while respecting the buffered Voronoi cell constraint. Our motion within the cell also depends on a planning horizon (longer horizon will lead to more conservative behavior) and a maximum speed. The commander and controller do not need to know if BVCA is enabled.

BVCA does not attempt to smooth the modified setpoints, so the output may be discontinuous or far from the current robot state. The controller must be able to handle this kind of input. Currently, only the PID controller is confirmed to work with BVCA. High-gain controllers like Mellinger may become unstable.

The volume for collision checking is a tall ellipsoid. This accounts for the downwash effect: Due to the fast-moving stream of air produced by the rotors, the safe distance to pass underneath another rotorcraft is much further than the safe distance to pass to the side. The radii of the ellipsoid can be set by using the parameters below.

A bounding box may be specified, for example when using a motion capture system. The box is applied to the Crazyflie’s center point only; the ellipsoid collision volume is ignored. The box can be set to +/- infinity if the flight space is unbounded.

[1] Zhou, Dingjiang, et al. “Fast, on-line collision avoidance for dynamic vehicles using buffered voronoi cells.” IEEE Robotics and Automation Letters 2.2 (2017): 1047-1054.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

commander

The high level commander handles the setpoints from within the firmware based on a predefined trajectory. This was merged as part of the Crazyswarm project of the USC ACT lab (see this blogpost). The high-level commander uses a planner to generate smooth trajectories based on actions like ‘take off’, ‘go to’ or ‘land’ with 7th order polynomials. The planner generates a group of setpoints, which will be handled by the High level commander and send one by one to the commander framework.

It is also possible to upload your own custom trajectory to the memory of the Crazyflie, which you can try out with the script examples/autonomous_sequence_high_level of.py in the Crazyflie python library repository.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

cppm

The CPPM (Combined Pulse Position Modulation) parameters configure the maximum angle/rate output given a maximum stick input for CRTP packets with emulated CPPM channels (e.g. RC transmitters connecting directly to the NRF radio, often with a 4-in-1 Multimodule), or for CPPM channels from an external receiver.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

cpu

This parameter group contain read-only parameters pertaining to the CPU in the Crazyflie.

These could be used to identify an unique quad.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

crtpsrv

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

ctrlAtt

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

ctrlINDI

Tuning settings for INDI controller for the attitude and accelerations of the Crazyflie

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

ctrlMel

Tunning variables for the full state Mellinger Controller

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

deck

The deck parameter group tells us which decks are connected. There is one parameter per official deck and the parameter is nonzero if the deck is connected.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

firmware

Read-only parameters that describe the current quad firmware.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

flapper

Current sensor parameters

Flapper Drone configration parameters

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

flightmode

There are 2 levels to control: Position (X, Y, Z) and Attitude (pitch, roll, yaw or in quaternions)

These can be controlled in different modes: Absolute mode, Velocity mode or Disabled

These parameters have impact on which level and mode to use.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

health

Health modules that is trying to find problems such as unbalanced propellers or a bad power path/battery.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

hlCommander

computes smooth setpoints based on high-level inputs such as: take-off, landing, polynomial trajectories.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

imu_sensors

An inertial measurement unit (IMU) is an electronic device that measures and reports a body’s specific force, angular rate, and sometimes the orientation of the body, using a combination of accelerometers, gyroscopes, and sometimes magnetometers.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

imu_tests

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

kalman

Tuning parameters for the Extended Kalman Filter (EKF) estimator

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

led

Parameters governing the onboard LEDs

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

lighthouse

Parameters and settings for the Lighthouse positioning system

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

loadcell

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

loco

The Loco Positioning System implements three different positioning modes: Two Way Ranging (TWR), Time Difference of Arrival 2 (TDoA 2) and Time Difference of Arrival 3 (TDoA 3)

TWR mode

In this mode, the tag pings the anchors in sequence, this allows it to measure the distance between the tag and the anchors. Using this information a theoretical minimum of 4 Anchors is required to calculate the 3D position of a Tag, but a more realistic number is 6 to add redundancy and accuracy. This mode is the most accurate mode and also works when the tag or quad leaves the space delimited by the anchors. The tag is actively communicating with the anchors in a time slotted fashion and in this mode only one tag or quad can be positioned with a maximum of 8 anchors.

TDoA 2 mode

In TDoA 2 mode, the anchor system is continuously sending synchronization packets. A tag listening to these packets can calculate the relative distance to two anchors by measuring the time difference of arrival of the packets. From the TDoA information it is possible to calculate the 3D position in space. In this mode the tag is only passively listening, so new tags do not add any load to the system which makes it possible to position any number of tags or quads simultaneously. This makes it a perfect mode for swarming.

Compared to TWR, TDoA 2 is more restrictive when it comes to the space where positioning works, ideally the tag should be within, or very close to, the space delimited by the anchor system. This means that TDoA 2 works best with 8 anchors placed in the corners of the flying space. In this space the accuracy and precision is comparable to TWR.

In this mode the anchor system is time slotted and synchronized and the number of anchors is limited to 8.

TDoA 3 mode

The TDoA 3 mode has many similarities with TDoA 2 and supports any number of tags or quads. The main difference is that the time slotted scheme of TDoA 2 has been replaced by a randomized transmission schedule which makes it possible to add more anchors. By adding more anchors the system can be scaled to larger spaces or span multiple rooms without line of sight between all anchors. It also makes it more robust and can handle loss or addition of anchors dynamically. The estimated position in this mode might be slightly more noisy compared to TDoA 2.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

locSrv

Service parameters for (external) positioning data stream through ctrp

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

memTst

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

motion

Settings and parameters for handling of the flowdecks measurements

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

motorPowerSet

Override power distribution to motors.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

multiranger

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

pid_attitude

Tuning settings for the gains of the PID controller for the attitude of the Crazyflie which consists of the Yaw Pitch and Roll

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

pid_rate

Tuning settings for the gains of the PID controller for the rate angles of the Crazyflie, which consists of the yaw, pitch and roll rates

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

pm

Power management parameters.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

posCtlPid

Tuning settings for the gains of the PID controller for the position of the Crazyflie ¨ in the body-yaw-aligned X & Y and global Z directions.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

posCtrlIndi

Tuning settings for the gains of the INDI controller for the position and velocity of the Crazyflie in the X, Y and Z direction in the global coordinate system.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

posEstAlt

Tuning setttings for the altitude estimator/filtering

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

powerDist

Power distribution parameters

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

radiotest

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

ring

The LED ring expansion deck contains two powerful front-facing white LEDs and 12 bottom-facing RGB individually addressable LEDs (it uses the same LEDs as used in the NeoPixel products by Adafruit).

The deck is designed to be installed as the last deck on the bottom of the quad. It does not have pass-through holes for the expansion port connector.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

sensfusion6

Sensor fusion is the process of combining sensory data or data derived from disparate sources such that the resulting information has less uncertainty than would be possible when these sources were used individually.

The sensfusion6 module uses an 3 axis accelerometer and a 3 axis gyro to get accurate attitude measurements.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

servo

“Servo” deck parameters

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

sound

The buzzer deck contains a low profile piezo buzzer.

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

stabilizer

Parameters to set the estimator and controller type for the stabilizer module

Variables

| Name | Core | Type | Description | | ————- | ————- | —– |—– |

Detailed Variable Information

back to group index

supervisor

The purpose of the supervisor is to monitor the system and its state. Depending on the situation, the supervisor can enable/disable functionality as well as take action to protect the system or humans close by.