9 Replies Latest reply on Mar 23, 2017 5:23 PM by Intel Corporation

    Intel Aero RTF drone compass

    VF_drones

      I am experiencing high level of inaccuracies in the compass:

      1. When I turn the drone, readings change but keep drifting for a while until they settle

      2. When I turn the drone 90 degrees at a time, readings don't settle to values indicating 90 degree turns.

       

      I am not sure, but I believe the Aero board is using the built in compass. The GPS board on the drone looks like is made by Yuneec and has a blox MAX-M8Q-0-01 chip on it.

      I also see cables coming out of a connector labelled compass on the Aero board cover.

       

      My questions:

      1. Is the system using the compass on the Aero board?

      2. If so, is there a way to connect an external compass and how can that be done? What are the HW connections, SW configurations required?

      3. Does the code look at accelerometer data at the same time it is updating heading based on compass?

        • 1. Re: Intel Aero RTF drone compass
          Intel Corporation
          This message was posted on behalf of Intel Corporation

          Hi VF_drones,

          Thanks for your interest in the Intel® Aero Platform for UAVs.

           

          I will address your concerns in order:

           

          1)  Is the system using the compass on the Aero board?

           

          Actually the compass is integrated on the quadcopter, not on the Intel Compute Board. You can confirm this information by looking at the hardware guide of Compute Board (Intel® Aero Compute Board Hardware Features and Usage Guide ) and by checking the specifications of the Intel Aero Ready to Fly (Intel® Aero Ready to Fly Drone | Intel® Software ).

           

          2) If so, is there a way to connect an external compass and how can that be done? What are the HW connections, SW configurations required?

           

          Yes, you can attach an external compass by using the 80-pin Accessories Connector Pinout Definition, for more information, please check the hardware guide of the Intel Aero Compute Board (Intel® Aero Compute Board Hardware Features and Usage Guide ).

           

          3) Does the code look at accelerometer data at the same time it is updating heading based on compass?

           

          What code exactly are you referring? Are you talking about the INS algorithm?

           

          Also, it would be great if you could tell me which software are you using to see the readings of the Drone heading.

           

          I will be waiting for your reply, have a nice day!

           

          Best Regards,
          -Jose P.

          • 2. Re: Intel Aero RTF drone compass
            mindThomas

            To answer your two first questions:

            1. When I turn the drone, readings change but keep drifting for a while until they settle

            2. When I turn the drone 90 degrees at a time, readings don't settle to values indicating 90 degree turns.

            This is the normal (but undesired) effect of an uncalibrated or badly calibrated magnetometer.

            You should install QGroundControl and connect to the WiFi of the drone and perform a Magnetometer calibration very gently.

            This should reduce these drift issues, scale errors and offsets.

             

            Jose; I think what we are all gently asking and requesting is which sensors are connected to the STM32 processor running the PX4 stack on the Intel Aero RTF boards?

            An external GPS is connected (as mentioned this looks like the Yuneec brand type) on the Intel Aero RTF drone, but does this GPS include a compass? The onboard sensors what are these used for?

            When do you expect to release schematics and further documentation?

             

            Regards Thomas

            • 3. Re: Intel Aero RTF drone compass
              Intel Corporation
              This message was posted on behalf of Intel Corporation

              Hi Thomas,

              Thanks for your interest in the Intel® Aero Platform for UAVs.

               

              We appreciate the suggestion that you made to VF_drones.

               

              Now, regarding your questions, please let us investigate and we will get back to you as soon as we have some useful information.

               

              By the way, regarding if the GPS has a compass, you can confirm that there is an integrated compass in this link Intel® Aero Ready to Fly Drone | Intel® Software , please check the Pre-assembled Quadcopter section.

               

              Have a nice day!

               

              Best Regards,
              -Jose P.

              • 4. Re: Intel Aero RTF drone compass
                VF_drones

                To be more exact, I am trying to find out how heading information is derived. Is it purely based on compass readings? Is IMU data used in conjunction with compass readings?

                • 5. Re: Intel Aero RTF drone compass
                  VF_drones

                  Also, when adding an external compass, should SW settings be changed?

                  • 6. Re: Intel Aero RTF drone compass
                    mindThomas

                    This is all related to the PX4 stack (Pixhawk) installed on the STM32 flight controller on board.

                    Please be aware that the compass is not a compass but rather a Magnetometer. The difference is the way they measure and the output. A magnetometer outputs the direction of a detected magnetic field (earth's magnetic field in this case).
                    The heading is derived from a filtered combination of the Accelerometer, Gyroscope and Magnetometer, yielding the attitude of the Quadcopter from which the heading can be extracted.

                    You can find more information here: https://dev.px4.io/tuning_the_ecl_ekf.html

                    • 7. Re: Intel Aero RTF drone compass
                      Intel Corporation
                      This message was posted on behalf of Intel Corporation

                      Hi guys,

                       

                      First, Thomas again thanks for answering VF_drones questions.

                      At last, the answer in this thread Re: Block Diagram  applies to all your questions. Also, you should know that we are still working on the documentation for the Intel Aero RTF.

                       

                      Thanks for your understanding.

                       

                      Best Regards,
                      -Jose P.

                      • 8. Re: Intel Aero RTF drone compass
                        mindThomas

                        Hi Jose.

                         

                        Thank you. Yes, that post and further posts definitely unveils answers to some of the questions, but still nothing confirmed from your side.

                        Why are you so secret about all this?

                         

                        Regards Thomas

                        • 9. Re: Intel Aero RTF drone compass
                          Intel Corporation
                          This message was posted on behalf of Intel Corporation

                          Hi Thomas,

                          We are diligently working on the documentation, we understand it must be frustrating having to wait, but we hope it will become available soon.

                          Best Regards,
                          -Jose P.