Search found 134 matches

by kristoffer
Wed Jan 15, 2020 10:45 am
Forum: Developer Discussions
Topic: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle
Replies: 8
Views: 507

Re: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle

It seems as you have hit two issues at the same time. The unwinding part is a feature of the high level commander, it is designed to rotate to yaw=0 at take off and landing. This is maybe a behaviour that we want to change and I created an issue for it https://github.com/bitcraze/crazyflie-firmware/...
by kristoffer
Wed Jan 15, 2020 8:39 am
Forum: Loco Positioning System
Topic: Different Positioning types
Replies: 3
Views: 90

Re: Different Positioning types

It is possible that the estimator can be improved :-)
The only idea I have at this point is that it might be related to accelerometers. Maybe some sort of scaling or calibration would improve the performance?
by kristoffer
Thu Jan 09, 2020 1:28 pm
Forum: Loco Positioning System
Topic: Different Positioning types
Replies: 3
Views: 90

Re: Different Positioning types

Hi! Not exactly sure what you are seeing. I would expect some noise on top of the signal, around +-0.1 m, but it looks like there is an overshoot as well that I don't understand. Are you using a mocap as a ground truth? Were you flying when recording the data or did you move the Crazyflie around by ...
by kristoffer
Wed Jan 08, 2020 12:41 pm
Forum: Developer Discussions
Topic: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle
Replies: 8
Views: 507

Re: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle

Is it possible for you to provide a python script that reproduces the problem? Preferably as simple as possible :-)
by kristoffer
Wed Jan 08, 2020 8:14 am
Forum: Developer Discussions
Topic: changing position
Replies: 5
Views: 401

Re: changing position

When the Crazyflie is sitting on the ground, the estimator will assume it is facing positive X (yaw = 0).
The only exception is
1. if you are using a positioning system that provides yaw (lighthouse or mocap)
2. you set the start yaw using the kalman.initialYaw parameter
by kristoffer
Fri Dec 27, 2019 11:24 am
Forum: Developer Discussions
Topic: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle
Replies: 8
Views: 507

Re: Crazyflie 2.1 rotating frantically and crashing at specific Yaw-Angle

Not sure what happens. We can compare to the spiral that we fly in the ICRA/IROS demos where we yaw all the time without problems. We made the Crazyflie fly the exact same path both with Bezier-Trajectories as well as go_to-commands from the high level commander, happens in both cases. Makes sense s...
by kristoffer
Thu Dec 19, 2019 3:59 pm
Forum: Support
Topic: LPS TWR Mode accuracy
Replies: 1
Views: 122

Re: LPS TWR Mode accuracy

Hi! We have seen this type of error as well sometimes but do not have a full understanding of what it is. There are a few things to check. 1. Make sure your anchor positions are correct and correspond to where your anchors are placed in space (within a few cm) 2. Make sure to start the Crazyflie fac...
by kristoffer
Thu Dec 19, 2019 8:43 am
Forum: Loco Positioning System
Topic: TDoA2 Truncating Clock Correction Measurements
Replies: 1
Views: 105

Re: TDoA2 Truncating Clock Correction Measurements

Hi! I must admit that I don't remember why we truncate them to 32 bits, I think the timestamps are 40 bits from the DW1000 chip (looks like that in the dwTime_t type at least). Since we clearly are indicating a 40 bit long bit mask (0x00FFFFFFFFul) in the code, I assume we had a good reason and it i...
by kristoffer
Wed Dec 18, 2019 8:46 am
Forum: External positioning systems
Topic: Lighthouse Yaw Offset
Replies: 7
Views: 630

Re: Lighthouse Yaw Offset

It unfortunately looks like one sensor is not working properly. Please send us an email on contact@bitcraze.io so we can sort out a replacement for you.