Washing machine appliance out-of-balance detection

1. A method for operating a washing machine appliance, the washing machine appliance having a tub and a basket rotatably mounted within the tub, the basket defining a chamber for receipt of articles for washing, the method comprising:

flowing a volume of liquid into the tub;

agitating articles within the tub for a first period, the tub containing the volume of liquid;

measuring movement of the tub during agitation of the articles within the tub, the tub containing the volume of liquid, wherein the movement is measured using an accelerometer and a gyroscope;

agitating articles within the tub for a second period when the final measured movement is greater than an out-of-balance movement threshold, the tub containing the volume of liquid;

draining liquid from the tub when the final measured movement is less than the out-of-balance movement threshold; and

spinning the basket after draining liquid from the tub,

wherein agitating articles within the tub comprises redistributing the articles during a tumbling cycle within the tub through a repeated starting-stopping pattern of agitation strokes according to a corresponding agitation profile prior to the step of draining liquid from the tub.

2. The method of claim 1 , wherein the tub defines an X-axis, a Y-axis and a Z-axis which are mutually orthogonal to each other, the Z-axis extending along a longitudinal direction and defining a center of the tub, and wherein the gyroscope measures movement about the Z-axis.

3. The method of claim 2 , wherein the accelerometer measures movement along the Y-axis.

4. The method of claim 3 , wherein the movement measured by the accelerometer is measured along a direction perpendicular to a vector that passes through the center.

5. The method of claim 1 , wherein the accelerometer is a first accelerometer, and further comprising a second accelerometer mounted to the tub.

6. The method of claim 5 , wherein the second accelerometer measures movement along the X-axis.

7. The method of claim 1 , wherein the step of measuring movement occurs after agitating articles within the tub for the first period and for an intermediate measurement period.

8. The method of claim 1 , wherein the step of measuring movement occurs during agitating articles within the tub for the first period.

9. The method of claim 1 , wherein, during the step of measuring movement, agitating of the articles is actively ceased upon determination that the measured movement is less than the out-of-balance movement threshold.

10. A washing machine appliance, comprising:

a tub;

a basket rotatably mounted within the tub, the basket defining a wash chamber for receipt of articles for washing;

a valve;

a nozzle configured for flowing liquid from the valve into the tub;

an agitation element;

a motor in mechanical communication with the basket, the motor configured for selectively rotating the basket within the tub and further configured for selectively rotating the agitation element;

a gyroscope mounted to the tub;

an accelerometer mounted to the tub; and

a controller in operative communication with the valve, motor, gyroscope and accelerometer, the controller configured for:

flowing a volume of liquid into the tub;

agitating articles within the tub for a first period, the tub containing the volume of liquid;

measuring movement of the tub during agitation of the articles within the tub, the tub containing the volume of liquid, wherein the movement is measured using the accelerometer and the gyroscope;

agitating articles within the tub for a second period when the final measured movement is greater than an out-of-balance movement threshold, the tub containing the volume of liquid;

draining liquid from the tub when the final measured movement is less than the out-of-balance movement threshold; and

spinning the basket after draining liquid from the tub,

wherein agitating articles within the tub comprises redistributing the articles during a tumbling cycle within the tub through a repeated starting-stopping pattern of agitation strokes according to a corresponding agitation profile prior to the step of draining liquid from the tub.

11. The washing machine appliance of claim 10 , wherein the tub defines an X-axis, a Y-axis and a Z-axis which are mutually orthogonal to each other, the Z-axis extending along a longitudinal direction and defining a center of the tub, and wherein the gyroscope measures movement about the Z-axis.

12. The washing machine appliance of claim 11 , wherein the accelerometer measures movement along the Y-axis.

13. The washing machine appliance of claim 12 , wherein the movement measured by the accelerometer is measured along a direction perpendicular to a vector that passes through the center.

14. The washing machine appliance of claim 10 , wherein the accelerometer is a first accelerometer, and further comprising a second accelerometer mounted to the tub.

15. The washing machine appliance of claim 14 , wherein the second accelerometer measures movement along the X-axis.

16. The washing machine appliance of claim 10 , wherein the step of measuring movement occurs after agitating articles within the tub for the first period and for an intermediate measurement period.

17. The washing machine appliance of claim 10 , wherein the step of measuring movement occurs during agitating articles within the tub for the first period.

18. The washing machine appliance of claim 10 , wherein, during the step of measuring movement, agitating of the articles is actively ceased upon determination that the measured movement is less than the out-of-balance movement threshold.

19. A method for operating a washing machine appliance, the washing machine appliance having a tub and a basket rotatably mounted within the tub, the basket defining a chamber for receipt of articles for washing, the method comprising:

performing a wash cycle, the wash cycle comprising flowing a volume of liquid into the tub, agitating articles within the tub, draining liquid from the tub after agitating the articles, and spinning the basket after draining liquid from the tub;

measuring movement of the tub during the wash cycle, wherein the movement is measured using an accelerometer and a gyroscope, the measuring comprising calculating motion at a point offset from the accelerometer and the gyroscope based on movement measured at the accelerometer and the gyroscope; and

altering a characteristic of the wash cycle when a final measured movement is greater than a movement threshold.