Method for determining the position of an actuating device, corresponding actuating device
A method determines the position of an actuating device of an element of an aircraft seat. The actuating device includes a calculating unit, an actuator movably mounted on an output shaft for actuating the element, the output shaft being connected to an angular position encoder so a position (X) of the actuator on the output shaft corresponds to a single angular position (θ) of the encoder. The method includes a preliminary submethod of automatically calibrating the actuating device including: placing the actuator at a predetermined position (Xref) corresponding to an expected angle value (θatt) of the encoder; measuring an initial positioning angle value (θini) of the encoder when the actuator shaft is in the predetermined position (Xref); comparing the initial positioning angle value (θini) and the expected angle value (θatt) calculating the angular offset of the encoder signal, with θdécal=(θini−θatt) [MODULO 360°], θdecal being between 0° and 359°.
1 . Actuating device of at least one element for actuating an aircraft seat, the actuating device comprising a calculating unit, an actuator mounted to be movable in translation and/or rotation on an output shaft so as the actuate the corresponding at least one element of an aircraft seat, said output shaft being connected to an angular position encoder so that a position (X) of the actuator on said output shaft corresponds to a single angular position ( 0 ) of the encoder, said device being configured to implement a method for determining the position of the actuating device, the method comprising a preliminary submethod of automatically calibrating said actuating device comprising the following steps:
a step of placing the actuator at a predetermined position (Xref) corresponding to an expected angle value (θatt) of the encoder;
a step of measuring an initial positioning angle value (θini) of the angular position encoder when the actuator shaft is in the predetermined position (Xref);
a step of comparing said initial positioning angle value (θini) and said expected angle value (θatt);
a step of calculating the angular offset (θdécal) of the angular position encoder signal, with θdécal=(θini−θatt) [MODULO 360°], θdécal being between 0° and 359°; and
a step of measuring the position (X (t)) of the actuator at a given moment according to the following relationship:
X
(
t
)
=
[
(
θ
+
θdécal
)
[
MODULO
360
°
]
]
K
+
X
min
with Xmin a minimum position of the actuator, and
with K a proportion coefficient between the angle value sent by the encoder and the value of the actuator position.
2 . The actuating device according to claim 1 , wherein the actuator can be moved between the minimum position (Xmin) corresponding to a single minimum angular position (θmin) of the encoder and a maximum position (Xmax) corresponding to a single maximum angular position (θmax) of the encoder, the deviation between the maximum angular position (θmax) and the minimum angular position (θmin) being less than 360 degrees.
3 . The actuating device according to claim 2 , wherein the deviation between the minimum position (Xmin) of the actuator and the maximum position (Xmax) of the actuator is between 100 mm and 800 mm.
4 . The actuating device according to claim 2 , wherein the deviation between the minimum position (Xmin) of the actuator and the maximum position (Xmax) of the actuator is between 500 mm and 700 mm.
5 . The actuating device according to claim 2 , wherein the deviation between the minimum position (Xmin) of the actuator and the maximum position (Xmax) of the actuator is equal to 600 mm.
6 . The actuating device according to claim 1 , the method further comprising a step of determining a position of at least one element to be actuated of an aircraft seat as a function of said position of the actuator at a given moment X (t).
7 . The actuating device according to claim 1 , further comprising a step of determining a minimum angular position (θmin) of the encoder corresponding to a minimum position (Xmin) of said actuator, and a maximum angular position (θmax) of the encoder corresponding to a maximum position (Xmax) of said actuator, the maximum angular position (θmax) and the minimum angular position (θmin) having an absolute variance of less than 360 degrees.
8 . The actuating device according to claim 7 , wherein if (θmin)>(θmax), the method comprises, for 355°<θ<365°:
a step of detecting the direction of rotation of said angular encoder;
a step of deactivating said step of measuring the position (X (t)) of the actuator at the given moment for a predetermined period.
9 . The actuating device according to claim 1 , wherein the encoder is a magnetic encoder having a periodical proportional increasing or decreasing ramp response, the angular position (θ) at a given moment being measured by measuring the magnetic axis of a radially magnetised magnet attached to the actuator.
10 . The actuating device according to claim 1 , wherein said calculating unit comprises a hysteresis filter.
11 . An aircraft seat, comprising at least one element of a movable seat mobile, wherein the seat is provided with at least one actuating device according to claim 1 .