Altitude

attachment:MK-Parameter/Altitude/altitude.gif BR The altitude control of the Mikrokopter is based on the pressure sensor. A PID algorithm controls the thrust of the engines so that the pressure value (=altitude) remains constant.

There are 2 different options to implement this control which can be selected choosing the option buttons beneath the checkbox Enable Altitude control.

1. Height limitation control

When Altitude limitation is inactive the total thrust is proportional to the throttle stick position. The altitude limitation weakens the thrust if the current height exceeds the setpoint. The MK can exceed the setpoint, however only if the thrust is greater than the total weight thus making the MK gain height. Thus the stable hovering point is always above the setpoint. The deviation is proportional to the throttle stick value. The Setpoint can be defined in several ways. For example you could define the Setpoint to a fixed value which one could never exceed. Furthermore you could define one Poti (from 1 to 4) together with the binded channel on the radio transmitter and change the value during flight, while the parameter Verstärkung (gain / rate) is used to provide scale. BR A further possibility is activating the check box use switch for setpoint , with which a poti should be likewise assigned to the Setpoint, so that one can switch the Altitude limitation on with the associated channel from the transmitter using a switch and the current height value as desired value is taken over at the same time.

2. Vario altitude control

With this option the altitude control takes over complete control of the thrust. One cannot any longer control it directly with gas-ticks from the transmitter. When altitude limitation is on the gas stick is now used to change the setpoint. A neutral point can be assigned for the gas stick with the parameter Stick neutral point. If gas stick value equals the parameter stick neutral point , then the neutral gas ticking position is used, with which the thrust compensates the all up weight (Hoverpoint).

If the gas-tick is over the neutral point, then the desired value of the height is shifted upward; if the gas-tick is below the neutral point, the desired value is downward shifted. The speed, with which the desired value moves, is proportional to the gas ticking position and can be likewise scaled over the parameter Verstärkung (gain / rate) . One sets thus a certain climbing or descent rate. This trim of the desired value can be optionally be indicated with activated option Acoustic Vario through a BEEP rate.

The altitude control should be configured insertable, thus the setpoint is assigned to a poti, so that one can activate the altitude control by the associated channel with a switch on the transmitter.

Enable Alitude control: altitude control activated (in the software has the same effect as the setting under [:MK-Parameter/Configuration:Configuration])
Setpoint: Indicates the desired height value. If the option use switch were activated one should select for setpoint a poti, which has an associated channel with a switch on the transmitter.
Min Gas: the gas is never reduced below this value if the height has been exceeded.
Altitude P: function to reduce thrust when height is above setpoint. The higher this value, the smaller is the flying range above the maximum height.
Barometric-D: Dampens the swinging behavior of the altitude control. Smaller changes of air pressure have thereby large effect on gas.
Z-ACC: Absorbs the swinging behavior by means of the acceleration sensor.
Verstärkung: if this value is increased makes possible higher flight altitudes. The setpoint is multiplied by this value.
Hover variation: limits the cutting down to the environment of the hover points, with smaller values calms down the adjustment but also reduces more the agility.
GPS-Z: Dampens the swinging behavior of the altitude control using the GPS height data.
Stick neutral point: it defines the neutral point of the gas stick. Climb and descent rate for the Vario altitude control mode. If the value is zero, then the natural hover point of the respective MKs is used.

$/!\$ Warning: if one takes off or lands with altitude control on there is danger of sudden rise at ground level due to ground effect feedback on altitude control, thus the danger of unexpected hopping exists

$/!\$ Warning: A possibly activated "mixer function (on the transmitter) of the altitude control switch on gas must be absolutely deactivated" since otherwise the entire regulation doesn't work!

KategorieSensor