> For the complete documentation index, see [llms.txt](https://yams.yassrobotics.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://yams.yassrobotics.com/api-reference/c++-reference/mechanisms/elevator.md).

# Elevator

Namespace: `yams::mechanisms::positional`\
Header: `<yams/mechanisms/positional/Elevator.h>`\
Inherits: `SmartPositionalMechanism`

**Java equivalent:** [Java Elevator](/api-reference/java-reference/mechanisms/elevator.md)

Controls a linear elevator mechanism. Position is measured in meters (carriage height).

***

## Constructor

```cpp
Elevator(config::ElevatorConfig* config, motorcontrollers::SmartMotorController* smc)
```

Both parameters are non-owning pointers. The `ElevatorConfig` and `SmartMotorController` must outlive the `Elevator` instance.

***

## State Queries

| Method      | Signature                          | Description             |
| ----------- | ---------------------------------- | ----------------------- |
| `GetHeight` | `units::meter_t GetHeight() const` | Current carriage height |

***

## Command Factories

| Method                  | Signature                                                                                           | Description                                                 |
| ----------------------- | --------------------------------------------------------------------------------------------------- | ----------------------------------------------------------- |
| `Run` (target)          | `frc2::CommandPtr Run(units::meter_t height)`                                                       | Drives to `height`, runs indefinitely                       |
| `Run` (supplier)        | `frc2::CommandPtr Run(std::function<units::meter_t()> height)`                                      | Supplier target, re-evaluated each iteration                |
| `RunTo` (target)        | `frc2::CommandPtr RunTo(units::meter_t height, units::meter_t tolerance = 0.01_m)`                  | Drives to `height`, ends within `tolerance`. Default: 1 cm. |
| `RunTo` (supplier)      | `frc2::CommandPtr RunTo(std::function<units::meter_t()> height, units::meter_t tolerance = 0.01_m)` | `RunTo` with supplier                                       |
| `Set` (duty cycle)      | `frc2::CommandPtr Set(double dutycycle)`                                                            | Open-loop duty cycle                                        |
| `Set` (supplier)        | `frc2::CommandPtr Set(std::function<double()> dutycycle)`                                           | Open-loop duty cycle with supplier                          |
| `SetVoltage`            | `frc2::CommandPtr SetVoltage(units::volt_t volts)`                                                  | Open-loop voltage output                                    |
| `SetVoltage` (supplier) | `frc2::CommandPtr SetVoltage(std::function<units::volt_t()> volts)`                                 | Open-loop voltage with supplier                             |

***

## Triggers

| Method    | Signature                                                                     | Description                                             |
| --------- | ----------------------------------------------------------------------------- | ------------------------------------------------------- |
| `IsNear`  | `frc2::Trigger IsNear(units::meter_t height, units::meter_t within = 0.01_m)` | True when current height is within `within` of `height` |
| `Gte`     | `frc2::Trigger Gte(units::meter_t height)`                                    | True when height ≥ threshold                            |
| `Lte`     | `frc2::Trigger Lte(units::meter_t height)`                                    | True when height ≤ threshold                            |
| `Between` | `frc2::Trigger Between(units::meter_t start, units::meter_t end)`             | True when height is in `[start, end]`                   |
| `Max`     | `frc2::Trigger Max() override`                                                | True when elevator is at its upper hard limit           |
| `Min`     | `frc2::Trigger Min() override`                                                | True when elevator is at its lower hard limit           |

***

## Other Public Methods

| Method                         | Signature                                                 | Description                                                  |
| ------------------------------ | --------------------------------------------------------- | ------------------------------------------------------------ |
| `SetHeight`                    | `void SetHeight(units::meter_t height)`                   | Directly commands the setpoint without a command wrapper     |
| `GetRelativeMechanismPosition` | `frc::Translation3d GetRelativeMechanismPosition() const` | 3D carriage position relative to the mechanism root          |
| `GetConfig`                    | `const config::ElevatorConfig& GetConfig() const`         | Returns the configuration this elevator was constructed with |
| `GetMotor`                     | `motorcontrollers::SmartMotorController* GetMotor()`      | Returns the underlying motor controller pointer              |
| `GetMechanismLigament`         | `frc::MechanismLigament2d* GetMechanismLigament()`        | The Mechanism2d visualization ligament                       |
| `GetMechanismRoot`             | `frc::MechanismRoot2d* GetMechanismRoot()`                | The Mechanism2d visualization root                           |
| `SimIterate`                   | `void SimIterate() override`                              | Advances elevator physics simulation one loop iteration      |
| `UpdateTelemetry`              | `void UpdateTelemetry() override`                         | Publishes current state to NetworkTables                     |
| `VisualizationUpdate`          | `void VisualizationUpdate() override`                     | Syncs Mechanism2d with current encoder reading               |
| `GetName`                      | `std::string GetName() const override`                    | Returns the mechanism name                                   |

***

## Example

```cpp
config::ElevatorConfig elevatorConfig;
elevatorConfig.WithMinHeight(0.0_m)
              .WithMaxHeight(1.5_m)
              .WithTelemetryName("Elevator");

motorcontrollers::SmartMotorControllerConfig motorConfig;
motorConfig.WithMotorInverted(false)
           .WithMotorGearing(gearing::MechanismGearing{1.0 / 9.0})
           .WithFeedback(1.2, 0.0, 0.0);

// motor is a SmartMotorController* created elsewhere
positional::Elevator elevator{&elevatorConfig, motor};

frc2::CommandPtr goToTop = elevator.RunTo(1.4_m);
```

{% @github-files/github-code-block url="<https://github.com/Yet-Another-Software-Suite/YAMS/blob/master/examples/cpptest/src/main/cpp/subsystems/ElevatorSubsystem.cpp>" %}

***

## See Also

* [Java Elevator](/api-reference/java-reference/mechanisms/elevator.md)
* [C++ ElevatorConfig](/api-reference/c++-reference/config/elevator-config.md)