Acceleration values reported with wrong sign

[scrouthtv]

Describe the bug
I am experiencing a regression in the ros2 branch, where Y and Z acceleration values are reported with the wrong sign.

To Reproduce
Steps to reproduce the behavior:

1. Checkout branch ros2
2. Run node with this configuration file:

microstrain_inertial_driver:
  ros__parameters:
    port: /dev/ttyUSB0

3. Confirm that the driver is publishing wrong acceleration values when exposing the IMU to gravity:

X value is correct:

Y value has the wrong sign:

Z value also has the wrong sign:

4. I've validated the raw sensor data to verify that the sensor is working ok:

With X vector pointing upwards, I received this packet:

0e 04 3f 80 08 e9 39 59 80 62 bb 19 03 43
 -> x = 1.0002719
 -> y = 0.00020742559
 -> z = -0.0023347891

With Y vector pointing upwards, I received this packet:

0e 04 3b 4e 03 72 3f 80 22 91 bb 83 09 8a
 -> x = 0.003143516
 -> y = 1.0010549
 -> z = -0.00399894

With Z vector pointing upwards, I received this packet:

  0e 04 bc 44 9c ca 3b a9 79 b7 3f 80 0a 6a
 -> x = -0.012000272
 -> y = 0.0051719802
 -> z = 1.0003178

5. Now I furthermore tested the ros2-3.x.x branch where everything is working as expected. I am currently not able to comprehend the entire version history since then, but I'd recommend writing some unit tests, e.g. using the above packets as examples and do a regression test.

Expected behavior
The driver would be reporting +1g = +9.81 m/s2 in whatever direction is currently pointing upwards.

Environment (please complete the following information):

• OS: Linux ubuntu 5.15.148-tegra 3dm-gx5-10 #1 SMP PREEMPT Tue Jan 7 17:14:38 PST 2025 aarch64 aarch64 aarch64 GNU/Linux
• Architecture: arm64
• ROS Version: ROS2 humble
• Sensor(s): 3DM-GX-25 (s/n 6253-...)

Launch Parameters

microstrain_inertial_driver:
  ros__parameters:
    port: /dev/ttyUSB0

[scrouthtv]

ETA: I haven't tested whether gyro and attitude data is also affected.