Washing machine and method of controlling washing machine

1. A method of controlling a washing machine comprising a casing, a tub suspended in the casing, a drum rotatably provided in the tub, a pulsator rotatably provided in the drum, and a driving unit rotating the pulsator, the method comprising:

(a) controlling the driving unit to rotate the pulsator while a certain amount of laundry is being provided in the drum;

(b) measuring a first property that varies in accordance with a resistant load applied to the driving unit while the pulsator is being rotated;

(c) calculating a first laundry load based on the first property;

(d) measuring a second property that varies in accordance with a vertical load applied by the tub while the certain amount of laundry is being provided in the drum;

(e) calculating a second laundry load based on the second property;

(f) determining that the laundry provided in the drum is in a dry state when the first laundry load calculated in (c) and the second laundry load calculated in (e) are substantially identical values; and

(g) determining that the laundry provided in the drum is in a wet state when a difference between the first laundry load calculated in (c) and the second laundry load calculated in (e) is equal to or greater than a predetermined value.

2. The method of claim 1 , further comprising:

(h) supplying wash water into the tub to a predetermined water level when it is determined that the laundry in the drum is in the wet state;

(i) calculating a third laundry load by performing (d) and (e) again while the tub is being filled with the wash water supplied in (h); and

(j) calculating a dry laundry load based on the third laundry load and an amount of the wash water supplied in (h).

3. The method of claim 2 , wherein a target water level for washing or rinsing is set in accordance with the dry laundry load.

4. The method of claim 2 , wherein a rotational speed of the drum or the pulsator is set in accordance with the dry laundry load.

5. The method of claim 1 , wherein the second laundry load is calculated on the basis of a degree to which a tub support mount, on which a suspension supporting the tub suspended from the casing, is deformed by the load applied to the tub support by the tub.

6. The method of claim 1 , wherein the second property is measured by a weight detecting sensor coupled to a suspension supporting the tub suspended from the casing.

7. The method of claim 1 , further comprising:

when it is determined that the laundry in the drum is in the wet state, outputting a message indicating that wet laundry is loaded in the drum.

8. The method of claim 7 , wherein the message is output in the form of a sound.

9. The method of claim 7 , wherein the message is visually displayed.

10. The method of claim 1 , further comprising:

before (a), measuring the second property; and

outputting a message indicative of a request to empty the drum when the second property is greater than a first preset value.

11. The method of claim 10 , further comprising:

when the second property measured before (a) is less than the first preset value, measuring the first property before (a); and

outputting a message indicative of a request to empty the drum when the first property measured before (a) is greater than a second preset value.

12. The method of claim 1 , further comprising:

determining a degree of unbalance based on the second property that varies in accordance with the vertical load applied by the tub.

13. The method of claim 1 , further comprising:

(h) supplying wash water into the tub after (c);

(i) performing a first spinning by rotating the drum after (h) such that wash water is extracted from the laundry;

(j) performing (d) and (e) again;

(k) obtaining a degree of water removal by comparing another laundry load obtained in (j) and the first laundry load obtained in (c); and

(l) a second spinning by rotating the drum such that wash water is extracted from the laundry when the degree of water removal is less than a reference degree of water removal.

14. The method of claim 13 , wherein a spinning time of the second spinning is determined in proportion to a degree to which the degree of water removal exceeds the reference degree of water removal.