# PX4 Community Q&A: June 21, 2023 **URL:** \ **Category:** PX4 Autopilot\ **Created:** [June 14, 2023, 5:00pm UTC](https://discuss.px4.io/t/px4-community-q-a-june-21-2023/32764 "2023-06-14T17:00:45Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![rroche](https://discuss.px4.io/user_avatar/discuss.px4.io/rroche/32/17635_2.png) [@rroche](https://discuss.px4.io/u/rroche)\ **Post date:** [June 14, 2023, 5:00pm UTC](https://discuss.px4.io/t/px4-community-q-a-june-21-2023/32764/1 "2023-06-14T17:00:45Z")
# June 21, 2023 ## Join us > **[Discord - Group Chat That’s All Fun & Games](https://discord.com/channels/1022170275984457759/1022185721450213396/1065287189791002776)** > > Discord is great for playing games and chilling with friends, or even building a worldwide community. Customize your own space to talk, play, and hang out. ## Agenda - Community Announcement - Community Q&A - General Discussions ## 📢 Community Announcement * * * ### A.1: v1.14 Release update > [@PX4 Maintainers Call: June 20, 2023](https://discuss.px4.io/t/px4-maintainers-call-june-20-2023/32744#release-v114-discussion-6): > > tear_off_calendar June 20, 2023 The maintainers meeting is a meeting for the developer team to coordinate on pressing issues and to plan the development of the PX4 Autopilot project, the community is welcome to join and listen, but won’t be able to speak unless specific access is granted ahead of time. selfie Meeting Link notebook_with_decorative_cover Agenda Finalize maintainer role description Identify maintainer opportunities Open mic for maintainers memo Meeting Notes PWM Output… - We have couple of release blockers, after resolved we will have release candidate - If you have a drone to contribute, it would be helpful to get more testings! - Perhaps v1.14 release features showcase event? (release party) - E.g. new actuators setup QGC workflow ## 🧑‍🤝‍🧑 Community Q&A (No deep technical discussions) * * * ### ❗ Guideline for asking a Question 1. Specify what you are trying to **achieve** 2. Specify what environment / **platform** you are using 3. Prepare a **Link** or **Document** to help understand if possible 4. First, ask the question on **Discord** or [create a **Github Issue**](https://github.com/PX4/PX4-Autopilot/issues/new/choose)! 5. If you take over 5 minutes for the question, please continue in Discord or a Github Issue. ### Q.1: HITL with Tiltrotor bug report - Darrens > > > \### Describe the bug > > Hi all, I'm trying to run tiltrotor VTOL HITL simulation i…n Gazebo Classic 11. I have connected to QGC and made the necessary modifications to the sdf file (setting serialEnabled to 1 and hilenabled to 1, as well as setting SYS\_HITL to 1). QGC was able to connect as well. However, when commanded to take off (autonomous mission) from QGC, the rotors on the model simply rotate slowly and the model doesnt move at all. I have previously done this with standard vtol with no problems. > > I compared the flight logs of the previous successful Standard VTOL HITL mission VS the current Tiltrotor VTOL HITL mission and discovered that the motor outputs in the Tiltrotor is only 0.1 VS 0.5 in the Standard VTOL. I think this is the cause as to why the rotors turn very slowly in the tiltrotor simulation, but I can't figure out why this is happening since I did not change airframe parameters except for VT\_TYPE and MAV\_TYPE. > > Can someone please point to where the problem could lie? Thank you very much! > > \### To Reproduce > > 1. Edit tiltrotor sdf file in models folder: in the mavlink plugin set serialenabled to 1, serialDevice to (usb port), hilenabled to 1 > 2. Open QGroundControl, in application settings listen only to UDP, in vehicle settings set safety setting to HIL mode, then close QGroundControl again > 3. Create new world file in worlds folder, include tiltrotor model > 4. In terminal, run: > \> cd PX4-Autopilot > \> DONT\_RUN=1 make px4\_sitl\_default gazebo-classic > \> source Tools/simulation/gazebo/setup\_gazebo.bash $(pwd) > \> gazebo Tools/simulation/gazebo/sitl\_gazebo/worlds/hitl\_ > > 5. Launch QGroundControl, plan mission and takeoff > > \### Expected behavior > > Rotors spin up fast and model takes off > > \### Screenshot / Media > > Tiltrotor VTOL Motor Outputs on the Left vs Standard VTOL Motor Outputs on the Right > !\[image\](https://github.com/PX4/PX4-Autopilot/assets/123139647/5a4b6d95-2346-4a46-850d-aca682ba3b56) > > > \### Flight Log > > \`\`\`txt > Tiltrotor VTOL Flight Log: > https://review.px4.io/plot\_app?log=d5ead83a-4169-41b1-9c76-c22ff2fd567a > > Standard VTOL Flight Log: > https://review.px4.io/plot\_app?log=1fac9d43-6548-47c3-b75a-d94e8a098f52 > \`\`\` > > > \### Software Version > > \`\`\`txt > HW arch: PX4\_FMU\_V5 > HW type: V5004000 > HW version: 0x004 > HW revision: 0x000 > PX4 git-hash: 70178b66d8f4bc18e74941821217b1ac8e5850b6 > PX4 version: 1.14.0 0 (17694720) > PX4 git-branch: main > OS: NuttX > OS version: Release 11.0.0 (184549631) > OS git-hash: 3f77354c0dc88793a47ff3b57595195ab45f7ba9 > Build datetime: Jun 21 2023 16:01:34 > Build uri: localhost > Build variant: default > Toolchain: GNU GCC, 9.3.1 20200408 (release) > PX4GUID: 000200000000303236323039510b003d003a > MCU: STM32F76xxx, rev. Z > Simulator: Gazebo Classic 11 > \`\`\` > > > \### Flight controller > > Pixhawk 4 Mini > > \### Vehicle type > > Hybrid VTOL > > \### How are the different components wired up (including port information) > > \_No response\_ > > \### Additional context > > \_No response\_ - Works in SITL, but in HITL the motor ouptut is too low for some reason - Standard VTOL works fine in HITL, but tiltrotor isn’t. Feedback - MAVLink interface for HITL is quite jenky. Why is HITL necessary? - To debug, first debug what the output of actuator goes through for mavlink ↔ sitl gazebo. Then, check what’s the pipeline for HITL for motor outputs - Check: Control allocator setup / `simulator_mavlink` for SITL and `mavlink` module for HITL - Make sure to figure out how the tiltrotor VTOL SITL is working fine, and where HITL differs from SITL for that. ### Q.2: Offboard causing drone to flip in v1.13.3 - Aiswarya Flight log: [Flight Review](https://review.px4.io/plot_app?log=e3878cb0-6fe4-4ee4-9108-58cf4f388f52) ![image](https://discuss.px4.io/uploads/default/original/2X/e/e9009971e15b853d47fa0a4cbd25b37e54d81312.png) Our drone was accepting mavros commands for arming, takeoff, etc but when I set the mode to offboard the drone immediately flipped and started behaving in an unstable way. I was publishing local position z value before I switched to offboard mode. We are using our quad with pixhawk 6x fc and px4. - Offboard setpoint is `local position` message - Have tried takeoff and landing, and works Another log: [Flight Review](https://review.px4.io/plot_app?log=011ffcda-4444-42a0-a443-dab8b8ed2325) Feedback - When the motor directions were all switched, as soon as yaw control is induced, it may cause a flip. So check motor directions! - Mark - Perhaps the position setpoint was too aggressive, and maybe current offboard control can’t handle that - Daniel - Try out manual mode and apply aggressive inputs, and make sure vehicle can track the attitude/rate well. Issue may be from rate controller. Analysis from Matthias: ![image](https://discuss.px4.io/uploads/default/original/2X/0/039d9963c797986b35b52e737c0999e1bb513154.png) > Try to find the rate control issue in Stabilized/Manual mode by flying aggressively. If found try to tune such that it does not get unstable in this case. When switching to offboard initialize the setpoint with the current vehicle state and then start moving it gently when you were able to take over. ### Q.3: QGC Herelink telmetry not working with Cube Orange - SJ Is there any work being done to update QGC Herelink Radio telemetry . I am currently on a Beta 1 update version and things are not working as required with the CUBE Orange - Herelink has their own fork based on 5.12 Qt, but it’s likely very outdated - Ramon also pinged cubepilot team, will get back with answer ## 🤔 General Discussions * * * ### D.1 : RTK GPS PR > > > This PR seeks to match \[https://github.com/PX4/PX4-GPSDrivers/pull/136\](https://…github.com/PX4/PX4-GPSDrivers/pull/136) - adding high precision RTK lat/lon/alt components from MSG\_NAV\_HPPOSLLH > > \### Solved Problem > This creates a possibility to operate coordinates with precision necessary to drive land based Rovers, for example, agricultural machines. > > \### Solution > please follow the link above for details > > \### Note: > once 1e-9 precision is available in \_gps\_position ORB message, it can be used in the following modules, as far as I know: > \- EKF2 > \- GPS Blending > > For my Rover project, I modified RoverPositionControl.cpp to subscribe to ORB\_ID(sensor\_gps) and use precise lat/lon for course planning. This won't be necessary if EKF2 could deliver centimeter level precision coordinates. - For lawnmower application - `int` data type for altitude limits precision to around 10 centimeters! Suggestions from SLG robotics: - Rename `lattitude` to `lat_deg`, to make search through code better and make unit more explicit Feedback: - If we change the data type, let’s change the naming as well, to always catch these migration cases in e.g. Flight Review - Change altitude members into float (achieve 0.1m precision), and rename to append unit ### D.2: Switching External vision ↔ GNSS Fusion - Farhang Currently in internal development with Ascend Engineering. Is it useful for PX4 in general?