Search found 377 matches

by whoenig
Fri Mar 12, 2021 9:25 am
Forum: Loco Positioning System
Topic: Positioning system
Replies: 1
Views: 245

Re: Positioning system

Hi, * LPS: +/- 10cm; high jitter; Jitter can be reduced if you also add the flow deck (not yet quantified how accurate that combination becomes) * Lighthouse: +/- 2cm; very low jitter; (roughly, we are still in the process of measuring this) * Motion Capture: sub-millimeter; lowest jitter LPS and Li...
by whoenig
Mon Mar 08, 2021 1:34 pm
Forum: General discussions
Topic: Problems Kalman filter computation copy
Replies: 3
Views: 344

Re: Problems Kalman filter computation copy

Personally, I do a lot of development in different stages: 1. Conceptual design: First develop the method and a prototype in a high-level language that allows you to iterate quickly (e.g., Python or Matlab). You can ignore limitations such as real-time performance, memory limitations, etc. at this s...
by whoenig
Thu Mar 04, 2021 10:35 pm
Forum: Loco Positioning System
Topic: Formation Control of Crazyfile using LPS
Replies: 3
Views: 290

Re: Formation Control of Crazyfile using LPS

You can have multiple logging configurations per quadrotor. Each logging configuration packet will be timestamped with the local clock. The 26 bytes are sufficient to get the current state estimate of the quadrotor within a single, timestamped, packet. For a swarm, you would configure each quadrotor...
by whoenig
Thu Mar 04, 2021 7:47 pm
Forum: Loco Positioning System
Topic: Formation Control of Crazyfile using LPS
Replies: 3
Views: 290

Re: Formation Control of Crazyfile using LPS

Software: The position information for LPS is only known onboard the drone. However, you can easily setup a logging configuration that streams that information back to your PC using the Crazyradio. Then, you can process this information for all drones, and send commander setpoints back over the radi...
by whoenig
Thu Mar 04, 2021 7:58 am
Forum: External positioning systems
Topic: What is the best approach to control CrazyFlies in a Vicon or Optitrack environment.
Replies: 3
Views: 400

Re: What is the best approach to control CrazyFlies in a Vicon or Optitrack environment.

[I am one of the authors of the Crazyswarm, so I am biased.] In general, I'd still recommend the Crazyswarm if you are planning to control more than 5 CFs. The Crazyswarm server is written in C++ and directly interfaces with the VICON/Optritrack libraries (in the same binary) to minimize latency. Yo...
by whoenig
Mon Mar 01, 2021 1:13 pm
Forum: General discussions
Topic: Nonparametric machine learning model written in CF2.1 firmware.
Replies: 3
Views: 273

Re: Nonparametric machine learning model written in CF2.1 firmware.

I am only aware of parametric ML models (e.g., Deep FeedForward Neural Networks: https://github.com/TaoChenOSU/quad_nn) with online inference (not learning). However, if you can find any pure C implementation of your desired nonparametric model, it should be possible to add to the firmware. Note tha...
by whoenig
Wed Feb 24, 2021 7:54 am
Forum: General discussions
Topic: Query about mathematical model of CF2.1
Replies: 1
Views: 264

Re: Query about mathematical model of CF2.1

The 2.1 has the same system ID as the CF 2.0, as only the IMU has been changed (& some other mechanical improvements). You can find most system identification parameters at https://www.research-collection.ethz.ch ... 850/214143.
by whoenig
Mon Feb 15, 2021 12:31 pm
Forum: Developer Discussions
Topic: Latency measurement between PC and Crazyflie
Replies: 1
Views: 390

Re: Latency measurement between PC and Crazyflie

We have added this in an experimental branch here: https://github.com/bitcraze/crazyflie-lib-python/blob/dev-nativedriver/sys_test/single_cf_grounded/test_link.py#L82-L113. The measured (roundtrip) latency is around 4ms on our systems, so for your control system you can expect about 2ms of latency. ...
by whoenig
Tue Feb 09, 2021 9:27 am
Forum: Support
Topic: Crazyflie does not fly properly
Replies: 29
Views: 1791

Re: Crazyflie does not fly properly

The ROS topic for /cf2/log1 uses a generic topic and is not aware of which variable you are trying to inspect. The proper way of visualizing is:

Code: Select all

rqt_plot /cf2/log1/values[0]
The order in the array matches the order of your configuration.
by whoenig
Fri Jan 29, 2021 7:41 pm
Forum: Support
Topic: Crazyflie does not fly properly
Replies: 29
Views: 1791

Re: Crazyflie does not fly properly

For the error, please make sure you source your ROS workspace (source devel/setup.bash) in the shell you run rqt_plot from.