惯性传感器 #

介绍 #

The inertial class is used to control and access data from the IQ (2nd gen) Brain’s built-in Inertial Sensor. This sensor measures how the Brain is moving and turning.

惯性传感器由两部分组成。陀螺仪测量转向，例如航向、旋转、陀螺仪速率和方向。加速度计测量运动变化，例如沿 x 轴、y 轴和 z 轴的加速或减速。

类构造函数 #

inertial(
  turnType dir = turnType::right );

类析构函数 #

Destroys the inertial object and releases associated resources.

~inertial();

参数 #

范围	类型	描述
`dir`	`turnType`	Optional. The direction that returns positive values: `right` (default) — Right turns return positive values. `left` — Left turns return positive values.

范围

类型

描述

dir

turnType

Optional. The direction that returns positive values:

right (default) — Right turns return positive values.
left — Left turns return positive values.

示例 #

// Create the inertial instance
inertial myInertial = inertial(
    right);     // dir

成员功能 #

The inertial class includes the following member functions:

heading — Returns the direction the sensor is facing.
rotation — Returns how far the sensor has turned.
setHeading — Sets the sensor’s current heading to a new heading value.
setRotation — Sets the sensor’s current rotation to a new rotation value.
calibrate — Calibrates the Inertial Sensor.
resetHeading — Resets the sensor’s current heading to 0 degrees.
resetRotation — Resets the sensor’s current rotation to 0 degrees.
isCalibrating — Returns whether the Inertial Sensor is currently calibrating.
changed — Registers a callback function that runs when the heading changes.
installed — Returns whether the Inertial Sensor is installed.
acceleration — Returns how quickly the sensor is speeding up or slowing down on the selected axis.
gyroRate — Returns how fast the sensor is rotating on the selected axis.
orientation — Returns the Inertial Sensor’s roll, pitch, or yaw angle.
collision — Registers a callback function that runs when a collision is detected.
setTurnType — Sets which turn direction returns positive heading values.
getTurnType — Returns which turn direction produces positive values.

Before calling any inertial member functions, an inertial instance must be created, as shown below:

/* This constructor is required when using VS Code.
Inertial Sensor configuration is generated automatically
in VEXcode with the IQ (2nd gen) Brain. Replace the values
as needed. */

// Create the inertial instance
inertial myInertial = inertial();

heading #

航向角是指传感器朝向的方向，以度为单位，范围从 0 到 359.99。此函数返回传感器的当前航向角。

初始航向为0度。如果传感器旋转超过359.99度，航向将回落至0度。

Available Functions

double heading( rotationUnits units = degrees );

Parameters

范围	类型	描述
`units`	`rotationUnits`	The heading unit: `deg` / `degrees` (default) — degrees `turns` / `rev` — revolutions

范围

类型

描述

units

rotationUnits

The heading unit:

deg / degrees (default) — degrees
turns / rev — revolutions

Return Values

Returns a double representing the current heading of the sensor in the specified units.

Notes

The heading value is wrapped between 0 and 359.99 degrees. Use rotation to access the continuous rotation value.

Examples

// Turn, then show the current heading
Drivetrain.turnFor(right, 450, degrees);
Brain.Screen.print("%f", myInertial.heading(degrees));

rotation #

返回惯性传感器的当前旋转角度。

旋转角度是指传感器转动的程度。与航向不同，旋转角度可以超过 359.99 度，也可以低于 0 度。例如，向右旋转两圈，旋转角度为 720 度。从 0 度向左旋转一圈，旋转角度为 -360 度。

Available Functions

double rotation( rotationUnits units = degrees );

Parameters

范围	类型	描述
`units`	`rotationUnits`	The rotation unit: `deg` / `degrees` (default) — degrees `turns` / `rev` — revolutions

范围

类型

描述

units

rotationUnits

The rotation unit:

deg / degrees (default) — degrees
turns / rev — revolutions

Return Values

Returns a double representing the current rotation in the specified units.

Notes

The rotation value is continuous and does not wrap between 0 and 359.99 degrees. Use heading to access the wrapped heading value.

Examples

// Turn, then show the current rotation
Drivetrain.turnFor(right, 450, degrees);
Brain.Screen.print("%f", myInertial.rotation(degrees));

setHeading #

航向角是指传感器朝向的方向，以度为单位，范围从 0 到 359.99。此功能将惯性传感器的当前航向角更改为新的航向角值。

例如，如果传感器已转向右侧，将航向设置为 0 度，则该右侧位置将成为新的 0 度。然后，传感器可以根据该新方向跟踪其他航向。

Available Functions

void setHeading( double        value,
                 rotationUnits units );

Parameters

范围	类型	描述
`value`	`double`	要设置的传感器航向值，单位为度。该值可以介于 0 到 359.99 之间。
`units`	`rotationUnits`	The heading unit: `deg` / `degrees` — degrees `turns` / `rev` — revolutions

范围

类型

描述

value

double

要设置的传感器航向值，单位为度。该值可以介于 0 到 359.99 之间。

units

rotationUnits

The heading unit:

deg / degrees — degrees
turns / rev — revolutions

Return Values

此函数不返回值。

Examples

// Turn the robot around
myInertial.setHeading(180, degrees);
Drivetrain.turnToHeading(0, degrees);

setRotation #

将惯性传感器的当前旋转角度设置为指定值。

旋转角度是指传感器转动的幅度。与航向不同，旋转角度可以超过 359.99 度，也可以低于 0 度。

Available Functions

void setRotation( double        value,
                  rotationUnits units );

Parameters

范围	类型	描述
`value`	`double`	要设置的传感器旋转值，以度为单位。可以是整数或小数。
`units`	`rotationUnits`	The rotation unit: `deg` / `degrees` — degrees `turns` / `rev` — revolutions

范围

类型

描述

value

double

要设置的传感器旋转值，以度为单位。可以是整数或小数。

units

rotationUnits

The rotation unit:

deg / degrees — degrees
turns / rev — revolutions

Return Values

此函数不返回值。

Examples

// Turn the robot around
myInertial.setRotation(-180, degrees);
Drivetrain.turnToRotation(0, degrees);

calibrate #

校准惯性传感器。

校准有助于传感器正确测量转弯角度。校准过程中请保持传感器静止。如果在校准过程中传感器移动，则航向、旋转、陀螺仪速率和方向值可能无法正确测量。

Available Functions

void calibrate( );

Parameters

此函数不接受任何参数。

Return Values

此函数不返回值。

Notes

校准过程中，传感器应保持静止。
Use isCalibrating to determine when calibration has completed.

resetHeading #

将惯性传感器的当前航向重置为 0 度。

使用此功能后，传感器的当前方向将变为新的 0 度航向。

Available Functions

void resetHeading();

Parameters

此函数不接受任何参数。

Return Values

此函数不返回值。

resetRotation #

将惯性传感器的当前旋转角度重置为 0 度。

使用此功能后，传感器将从新的 0 度旋转值开始跟踪未来的旋转。

Available Functions

void resetRotation();

Parameters

此函数不接受任何参数。

Return Values

此函数不返回值。

isCalibrating #

返回惯性传感器当前是否正在校准。

Available Functions

bool isCalibrating();

Parameters

此函数不接受任何参数。

Return Values

返回一个布尔值，指示惯性传感器是否正在校准：

true — The sensor is currently calibrating.
false — The sensor is not currently calibrating.

changed #

注册一个回调函数，当惯性传感器的航向值发生变化时，该函数将运行。

Available Functions

void changed( void (* callback)(void) );

Parameters

范围	类型	描述
`callback`	`void (*)(void)`	A pointer to a function that will be called when the heading value changes. The function must take no parameters and return `void`.

Return Values

此函数不返回值。

Examples

Define the callback function (outside of int main())

// Display the heading when the Inertial Sensor's heading value changes.
void onHeadingChanged() {
  Brain.Screen.clearScreen();
  Brain.Screen.setCursor(1, 1);
  Brain.Screen.print("Heading: %.2f", myInertial.heading());
}

int main() {
  // Run onHeadingChanged when the Inertial Sensor's heading value changes.
  myInertial.changed(onHeadingChanged);
}

installed #

返回惯性传感器是否已安装并连接。

Available Functions

bool installed();

Parameters

此函数不接受任何参数。

Return Values

返回一个布尔值，指示惯性传感器是否已安装并连接：

true — The sensor is connected and responding.
false — The sensor is not connected or not detected.

acceleration #

加速度是指传感器加速或减速的快慢。此函数返回惯性传感器在所选轴上的加速度，范围从 -4.0 G 到 4.0 G。

A G is a unit used to measure acceleration. 1 G is about the acceleration you feel from gravity while sitting still. The value can be positive or negative depending on the direction of acceleration on the selected axis.

Available Functions

double acceleration( axisType axis );

Parameters

范围	类型	描述
`axis`	`axisType`	The axis to measure acceleration on: `xaxis` `yaxis` `zaxis`

范围

类型

描述

axis

axisType

The axis to measure acceleration on:

xaxis
yaxis
zaxis

Return Values

Returns a double representing the acceleration along the specified axis in G (gravitational units).

Notes

Acceleration values are reported in units of G.

gyroRate #

陀螺仪转速是指惯性传感器旋转的速度。此函数返回惯性传感器在所选轴上的当前旋转速度。

该值可以是正数也可以是负数，具体取决于传感器绕该轴旋转的方向。

Available Functions

double gyroRate( axisType      axis,
                 velocityUnits units );

Parameters

范围	类型	描述
`axis`	`axisType`	The axis to return the gyro rate from: `xaxis` `yaxis` `zaxis`
`units`	`velocityUnits`	The gyro rate unit: `dps` — degrees per second `rpm` — revolutions per minute

范围

类型

描述

axis

axisType

The axis to return the gyro rate from:

xaxis
yaxis
zaxis

units

velocityUnits

The gyro rate unit:

dps — degrees per second
rpm — revolutions per minute

Return Values

Returns a double representing the current rotation speed along the specified axis in the selected units.

Examples

// Display the rate of change of rotation while turning in dps
Drivetrain.turn(right);
wait(1, seconds);

Brain.Screen.print(myInertial.gyroRate(zaxis, dps));

Drivetrain.stop();

orientation #

方向是指惯性传感器在选定旋转轴上的当前角度。此函数返回惯性传感器在指定轴上的当前方向。

横滚、俯仰和偏航描述了传感器倾斜或旋转的不同方式。

Available Functions

double orientation(
  orientationType type,
  rotationUnits   units );

Parameters

范围	类型	描述
`type`	`orientationType`	The orientation angle to return: `pitch` `roll` `yaw`
`units`	`rotationUnits`	The orientation unit: `deg` / `degrees` — degrees `turns` / `rev` — revolutions

范围

类型

描述

type

orientationType

The orientation angle to return:

pitch
roll
yaw

units

rotationUnits

The orientation unit:

deg / degrees — degrees
turns / rev — revolutions

Return Values

Returns a double representing the selected orientation angle in the specified units.

Examples

while (true) {
  Brain.Screen.clearScreen();
  Brain.Screen.setCursor(1,1);
  // Show the Inertial Sensor's orientation value
  // for roll in degrees
  double orient = myInertial.orientation(roll, deg);
  Brain.Screen.print("%f", orient);
  wait(0.1, seconds);
}

collision #

注册一个回调函数，当惯性传感器检测到突然冲击或碰撞时，该函数将运行。

Available Functions

void collision( void (* callback)(axisType, double, double, double) );

Parameters

范围	类型	描述
`callback`	`void (*)(axisType, double, double, double)`	A pointer to a function that will be called when a collision is detected. The callback function must accept the following parameters: `axisType` — The axis on which the collision was detected. Acceleration values at the time of impact, in order: `double` — Acceleration along the x-axis (in G). `double` — Acceleration along the y-axis (in G). `double` — Acceleration along the z-axis (in G). The function must return `void`.

范围

类型

描述

callback

void (*)(axisType, double, double, double)

A pointer to a function that will be called when a collision is detected. The callback function must accept the following parameters:

axisType — The axis on which the collision was detected.
Acceleration values at the time of impact, in order:
- double — Acceleration along the x-axis (in G).
- double — Acceleration along the y-axis (in G).
- double — Acceleration along the z-axis (in G).

The function must return void.

Return Values

此函数不返回值。

Examples

Define the callback function (outside of int main())

// Display a message when the Inertial Sensor detects a collision.
void onCollision(axisType axis, double x, double y, double z) {
  Brain.Screen.print("Collision detected!");
}

int main() {
  // Run onCollision when the Inertial Sensor detects a collision.
  myInertial.collision(onCollision);
}

setTurnType #

设置转向方向返回正值。

Available Functions

void setTurnType( turnType dir );

Parameters

范围	类型	描述
`dir`	`turnType`	The direction that returns positive values: `right` `left`

范围

类型

描述

dir

turnType

The direction that returns positive values:

right
left

Return Values

此函数不返回值。

Notes

This setting affects how heading and rotation report positive and negative values.
Calling this function overrides the dir value specified when constructing the inertial object.

getTurnType #

返回转向方向产生正值的结果。

Available Functions

turnType getTurnType();

Parameters

此函数不接受任何参数。

Return Values

Returns a turnType indicating which direction produces positive values:

right — Clockwise rotation returns positive values.
left — Counterclockwise rotation returns positive values.

Notes

This value is set during construction of the inertial object or by calling setTurnType.