Arrangement and method for controlling at least one operation of a work machine and work machine

1 . An arrangement configured to control at least one operation of a work machine, the work machine comprising at least one structural element, at least one pressure medium operated actuator configured to establish said at least one operation, and at least one detection device configured to determine the position of the at least one structural element of the work machine, the arrangement comprising:

a control valve arrangement configured to control said actuator, and

a control device configured to control said control valve arrangement,

wherein said control device is configured to control said control valve arrangement to adjust the pressure and/or volume flow on a return line of said actuator as dependent on said position of said at least one structural element,

wherein the control device is further configured to adjust the pressure and/or volume flow on the return line of said actuator via said control valve arrangement as dependent on the speed and/or acceleration of said at least one structural element,

wherein the position of said at least one structural element comprises a tilt angle of said at least one structural element in the direction of at least one axis of the at least one structural element in relation to a reference direction,

wherein the control device is configured to adjust the pressure and/or volume flow on the return line of said actuator via said control valve arrangement as dependent on a tilt angle of at least one body part of the work machine, so that the pressure and/or volume flow on the return line of said actuator is adjusted as dependent on the tilt angle caused by an inclination of a working surface of the work machine,

wherein the at least one detection device comprises an inertial measurement unit (IMU), and

wherein the work machine is a mobile work machine, the mobile work machine being a forwarder, a harvester, or another forest machine.

2 . An arrangement as claimed in claim 1 , wherein said control valve arrangement comprises a meter-in meter-out valve.

3 . An arrangement as claimed in claim 1 , wherein said reference direction comprises a direction of a gravity vector.

4 . An arrangement as claimed in claim 1 , wherein the control device is configured to control the control valve arrangement to adjust the pressure on the return line of the actuator lower when the position of the at least one structural element and the direction of the movement of the actuator are such that the acceleration of the Earth's gravity resists the movement of the actuator than when the position of the at least one structural element and the direction of the movement of the actuator are such that the acceleration of the Earth's gravity accelerates the movement of the actuator.

5 . An arrangement as claimed in claim 1 , wherein the control device comprises a regulator comprising control codes to control the control valve arrangement to adjust the pressure and/or volume flow on the return line of the actuator, as well as means to receive at least feedback information to control the control valve arrangement.

6 . An arrangement as claimed in claim 1 , wherein said operation comprises moving at least one structural element of a boom structure or loader of the work machine in relation to said at least one structural element, whose position is detected by the detector device, and/or another structural element of the boom structure or loader.

7 . An arrangement as claimed in claim 1 , wherein said at least one structural element comprises the at least one body part of the work machine.

8 . A work machine comprising the arrangement as claimed in claim 1 .

9 . A non-transitory computer readable storage medium storing computer-readable program code executable by a processor to control the arrangement as claimed in claim 1 .

10 . An arrangement as claimed in claim 1 , wherein the operation includes moving the at least one structural element to, and stopping the movement of the at least one structural element at, a desired position, via the at least one pressure medium operated actuator and the pressure on the return line.

11 . An arrangement as claimed in claim 10 , wherein the tilt angle is non-zero.

12 . A method for controlling at least one operation of a work machine, the work machine comprising at least one structural element, at least one pressure medium operated actuator for establishing said operation, and at least one detection device configured to determine the position of said at least one structural element of the work machine, the method comprising:

controlling a control valve arrangement so that said control valve arrangement adjusts the pressure and/or volume flow on a return line of said actuator as dependent on said position of said at least one structural element,

wherein the pressure and/or volume flow on the return line of said actuator is additionally adjusted via said control valve arrangement as dependent on the speed and/or acceleration of said at least one structural element,

wherein the pressure and/or volume flow on the return line of said actuator is adjusted as dependent on a tilt angle of at least one body part of the work machine, so that the pressure and/or volume flow on the return line of said actuator is adjusted as dependent on the tilt angle caused by an inclination of a working surface of the work machine,

wherein the at least one detection device comprises an inertial measurement unit (IMU), and

wherein the work machine is a mobile work machine, the mobile work machine being a forwarder, a harvester, or another forest machine.

13 . A method as claimed in claim 12 , wherein said control valve arrangement comprises a meter-in meter-out valve.

14 . A method as claimed in claim 12 , wherein said position of the at least one structural element comprises a tilt angle of said at least one structural element in relation to at least one axis of the at least one structural element.

15 . A method as claimed in claim 12 , wherein the control valve arrangement is controlled to adjust the pressure on the return line of the actuator lower when said position of the at least one structural element and the direction of the movement of the actuator are such that the acceleration of the Earth's gravity resists the movement of the actuator than when said position of the at least one structural element and the direction of the movement of the actuator are such that the acceleration of the Earth's gravity accelerates the movement of the actuator.

16 . A method as claimed in claim 12 , wherein the control device comprises a regulator comprising control codes to control the control valve arrangement to adjust the pressure and/or volume flow on the return line of the actuator, as well as means to receive at least feedback information to control the control valve arrangement.

17 . A method as claimed in claim 12 , wherein said operation comprises moving at least one structural element of a boom structure or loader of the work machine in relation to said at least one structural element, whose position is detected by means of the detector device, and/or a second structural element of the boom structure or loader.

18 . A non-transitory computer readable storage medium storing computer-readable program code executable by a processor to perform the method as claimed in claim 12 .