# 保持模式 (多旋翼)

<img src="../../assets/site/position_fixed.svg" title="Position fix required (e.g. GPS)" width="30px" />

The _Hold_ flight mode causes the vehicle to stop and hover at its current GPS position and altitude.

:::tip
_Hold mode_ can be used to pause a mission or to help you regain control of a vehicle in an emergency.
It is usually activated with a pre-programmed switch.
:::

::: info

- Mode is automatic - no user intervention is _required_ to control the vehicle.
- Mode requires a global 3d position estimate (from GPS or inferred from a [local position](../ros/external_position_estimation.md#enabling-auto-modes-with-a-local-position)).
  - Flying vehicles can't switch to this mode without global position.
  - Flying vehicles will failsafe if they lose the position estimate.
  - Disarmed vehicles can switch to mode without valid position estimate but can't arm.
- Mode requires wind and flight time are within allowed limits (specified via parameters).
- 遥控开关可以在任何无人机上更改飞行模式。
- RC stick movement will [by default](#COM_RC_OVERRIDE) change the vehicle to [Position mode](../flight_modes_mc/position.md) unless handling a critical battery failsafe.

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:::

## 技术总结

The vehicle hovers at the current position and altitude.
The vehicle will first ascend to [NAV_MIN_LTR_ALT](#NAV_MIN_LTR_ALT) if the mode is engaged below this altitude.

RC stick movement will change the vehicle to [Position mode](../flight_modes_mc/position.md) (by [default](#COM_RC_OVERRIDE)).

### 参数

Hold mode behaviour can be configured using the parameters below.

| 参数                                                                                                                                                                      | 描述                                                                                                                                                                                                                                         |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| <a id="NAV_MIN_LTR_ALT"></a>[NAV_MIN_LTR_ALT](../advanced_config/parameter_reference.md#NAV_MIN_LTR_ALT) | This is the minimum altitude above Home the system will always obey in Hold mode if switched into this mode without specifying an altitude (e.g. through switch on RC). |
| <a id="COM_RC_OVERRIDE"></a>[COM_RC_OVERRIDE](../advanced_config/parameter_reference.md#COM_RC_OVERRIDE)                      | Controls whether stick movement on a multicopter (or VTOL in MC mode) causes a mode change to [Position mode](../flight_modes_mc/position.md). 可以分别为自动模式和 offboard 模式启用此功能，默认情况下在自动模式下启用此功能。            |
| <a id="COM_RC_STICK_OV"></a>[COM_RC_STICK_OV](../advanced_config/parameter_reference.md#COM_RC_STICK_OV) | The amount of stick movement that causes a transition to [Position mode](../flight_modes_mc/position.md) (if [COM_RC_OVERRIDE](#COM_RC_OVERRIDE) is enabled). |

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## 另见

[Hold Mode (FW)](../flight_modes_fw/hold.md)