# Test MC_09 - VIO (Visual-Inertial Odometry)

## Objective

Test that external vision (VIO) works as expected

## Preflight

Disconnect all GPS / compasses and ensure vehicle is using VIO for navigation

Ensure that the drone can go into [Altitude](../flight_modes_mc/altitude.md) / [Position](../flight_modes_mc/position.md) mode while still on the ground

Ensure there are no other sources of positioning besides VIO:

- [EKF2_OF_CTRL](../advanced_config/parameter_reference.md#EKF2_OF_CTRL): `0`
- [EKF2_GPS_CTRL](../advanced_config/parameter_reference.md#EKF2_GPS_CTRL): `0`
- [EKF2_EV_CTRL](../advanced_config/parameter_reference.md#EKF2_EV_CTRL): `15`
- [SYS_HAS_MAG](../advanced_config/parameter_reference.md#SYS_HAS_MAG): `0`

## Flight Tests

❏ [Altitude mode](../flight_modes_mc/altitude.md)

    ❏ Vertical position should hold current value with stick centered

    ❏ Pitch/Roll/Yaw response 1:1

    ❏ Throttle response set to climb/descent rate

❏ [Position mode](../flight_modes_mc/position.md)

    ❏ Horizontal position should hold current value with stick centered

    ❏ Vertical position should hold current value with stick centered

    ❏ Throttle response set to climb/descent rate

    ❏ Pitch/Roll/Yaw response set to pitch/roll/yaw rates

## Landing

❏ Land in either Position or Altitude mode with the throttle below 40%

❏ Upon touching ground, copter should disarm automatically within 2 seconds (default: see [COM_DISARM_LAND](../advanced_config/parameter_reference.md#COM_DISARM_LAND))

## Expected Results

- Take-off should be smooth as throttle is raised
- Drone should hold altitude in Altitude mode without wandering
- Drone should hold position within 1 meter in Position mode without pilot moving sticks
- No oscillations should present in any of the above flight modes
- Upon landing, copter should not bounce on the ground