Imu

数据结构

字节索引	类型	字段含义
0-7	float64	X 轴姿态四元数
8-15	float64	Y 轴姿态四元数
16-23	float64	Z 轴姿态四元数
24-31	float64	W 轴姿态四元数
32-39	float64	X 轴角速度
40-47	float64	Y 轴角速度
48-55	float64	Z 轴角速度
56-63	float64	X 轴线加速度
64-71	float64	Y 轴线加速度
72-79	float64	Z 轴线加速度

Imu 固定为 80 字节

示例

C++ 示例

struct Vector3 {
  double x;
  double y;
  double z;
};

struct Quaternion {
  double x;
  double y;
  double z;
  double w;
};

struct Imu {
  Quaternion orientation;
  Vector3 angular_velocity;
  Vector3 linear_acceleration;
};

Rust 示例

#[repr(C)]
#[derive(Clone, Copy, Debug, Default)]
pub struct Vector3 {
    pub x: f64,
    pub y: f64,
    pub z: f64,
}

#[repr(C)]
#[derive(Clone, Copy, Debug, Default)]
pub struct Quaternion {
    pub x: f64,
    pub y: f64,
    pub z: f64,
    pub w: f64,
}

#[repr(C)]
#[derive(Clone, Copy, Debug, Default)]
pub struct Imu {
    pub orientation: Quaternion,
    pub angular_velocity: Vector3,
    pub linear_acceleration: Vector3,
}

const _: () = {
    assert!(core::mem::size_of::<Vector3>() == 24);
    assert!(core::mem::size_of::<Quaternion>() == 32);
    assert!(core::mem::size_of::<Imu>() == 80);
    assert!(core::mem::align_of::<Imu>() == 8);
};

Dart 示例

import 'dart:typed_data';

final class ImuView {
  static const int byteLength = 80;

  final ByteData data;

  ImuView(ByteBuffer buffer, [int offsetInBytes = 0])
      : data = ByteData.view(buffer, offsetInBytes, byteLength);

  double get orientationX => data.getFloat64(0, Endian.little);
  set orientationX(double value) => data.setFloat64(0, value, Endian.little);

  double get orientationY => data.getFloat64(8, Endian.little);
  set orientationY(double value) => data.setFloat64(8, value, Endian.little);

  double get orientationZ => data.getFloat64(16, Endian.little);
  set orientationZ(double value) => data.setFloat64(16, value, Endian.little);

  double get orientationW => data.getFloat64(24, Endian.little);
  set orientationW(double value) => data.setFloat64(24, value, Endian.little);

  double get angularVelocityX => data.getFloat64(32, Endian.little);
  set angularVelocityX(double value) => data.setFloat64(32, value, Endian.little);

  double get angularVelocityY => data.getFloat64(40, Endian.little);
  set angularVelocityY(double value) => data.setFloat64(40, value, Endian.little);

  double get angularVelocityZ => data.getFloat64(48, Endian.little);
  set angularVelocityZ(double value) => data.setFloat64(48, value, Endian.little);

  double get linearAccelerationX => data.getFloat64(56, Endian.little);
  set linearAccelerationX(double value) => data.setFloat64(56, value, Endian.little);

  double get linearAccelerationY => data.getFloat64(64, Endian.little);
  set linearAccelerationY(double value) => data.setFloat64(64, value, Endian.little);

  double get linearAccelerationZ => data.getFloat64(72, Endian.little);
  set linearAccelerationZ(double value) => data.setFloat64(72, value, Endian.little);
}

Java 示例

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.DoubleBuffer;

public final class ImuView {
  public static final int BYTE_LENGTH = Double.BYTES * 10;

  private final DoubleBuffer values;

  public ImuView(ByteBuffer buffer, int offset) {
    if (offset < 0 || offset + BYTE_LENGTH > buffer.capacity()) {
      throw new IndexOutOfBoundsException("Imu payload requires 80 bytes");
    }
    this.values = buffer.order(ByteOrder.LITTLE_ENDIAN)
        .slice(offset, BYTE_LENGTH)
        .asDoubleBuffer();
  }

  public double orientationX() { return values.get(0); }
  public void orientationX(double value) { values.put(0, value); }

  public double orientationY() { return values.get(1); }
  public void orientationY(double value) { values.put(1, value); }

  public double orientationZ() { return values.get(2); }
  public void orientationZ(double value) { values.put(2, value); }

  public double orientationW() { return values.get(3); }
  public void orientationW(double value) { values.put(3, value); }

  public double angularVelocityX() { return values.get(4); }
  public void angularVelocityX(double value) { values.put(4, value); }

  public double angularVelocityY() { return values.get(5); }
  public void angularVelocityY(double value) { values.put(5, value); }

  public double angularVelocityZ() { return values.get(6); }
  public void angularVelocityZ(double value) { values.put(6, value); }

  public double linearAccelerationX() { return values.get(7); }
  public void linearAccelerationX(double value) { values.put(7, value); }

  public double linearAccelerationY() { return values.get(8); }
  public void linearAccelerationY(double value) { values.put(8, value); }

  public double linearAccelerationZ() { return values.get(9); }
  public void linearAccelerationZ(double value) { values.put(9, value); }
}