Using the vertical derivative estimate prevents vertical velocity offsets caused by estimation vertical velocity errors preventing the vehicle disarming.
Before that, different modules (ekf2, commander & land detector) changed
params upon different events:
- ekf2 & commander set params after disarm
- land detector set params on land detected
If the 2 events were several 100ms appart, it led to 2 param saves, and
the latter param set could have been blocked by an ongoing save. And if
the land detector was blocked, it could lead to mag timeouts.
This patch makes all modules use the same event, thus only a single param
save will happen.
If we want to have guarantees to never block, we should introduce a
param_try_set() API method.
This change limits all mission items to the maximum flight altitude. The mission will still be executed and flown,
but the vehicle will never exceed the mission altitude. This ensures the vehicle can always reach the mission
items. Wether or not the entire mission should be rejected if it falls outside of the fenced area is enforced
in the mission feasibility checker function.
This commit is an attempt to fix a race condition happening on takeoff
between the land detector and the multicopter position controller.
Previously, an auto-takeoff leads to the following events:
1. A takeoff setpoint is given.
2. The thrust setpoint spikes because we don't enter smooth takeoff yet.
3. The land detector detects a takeoff because of the high thrust.
4. The position controller sees the landed state transition and
initiates the smooth takeoff. Thrust goes back down.
5. Depending on control gains the takeoff is successful or fails
if the smoothing takes too long which causes thrust to be too low, so
the land detector detects land again.
The two obvious problems with this are:
- The intermittent spike.
- The failed takeoff because of the smoothing leads to a delay..
With this change, the logic for a takeoff detection is moved from the
land detector to the position controller.
The events are now:
1. A takeoff setpoint is given.
2. The position controller detects the takeoff setpoint and initiates
the smooth takeoff.
3. As thrust ramps up, the land detector detects the take off.
In the same way, we now detect the intent to takeoff in manual,
altitude, control, position control in the position controller instead
of in the land detector.
The problem was signed vs unsigned mixing together with 64bit conversion:
int32_t flight_time = ...;
uint64_t _total_flight_time = ...;
_total_flight_time |= flight_time;
When flight_time is negative, the last line would first extend the sign
bit to the upper 32bits of the 64bit uint and then apply the bitwise OR.
The fix is to use an unsigned 32 bit value.
Daniel Agar