Washing machine appliances and methods for operation

Abstract

A washing machine appliance, including methods for operation, is provided herein. The washing machine appliance may have a tub and a basket rotatably mounted to a motor and within the tub. The basket may define a chamber for receipt of articles for washing. The method may include spinning the basket; calculating a torque value; accelerating the basket to an elevated rotational speed; determining an acceleration rate; determining a mass moment of inertia; and adjusting acceleration of the basket.

What is claimed is: 
     
         1 . A method for operating a washing machine appliance, the washing machine appliance having a tub and a basket rotatably mounted to a motor and within the tub, the basket defining a chamber for receipt of articles for washing, the method comprising:
 spinning the basket at a set dwell speed;   calculating a torque value based on the set dwell speed;   accelerating the basket to an elevated rotational speed;   determining an acceleration rate during accelerating the basket;   determining a mass moment of inertia based on the calculated torque value and the determined acceleration rate; and   adjusting acceleration of the basket according to the determined mass moment of inertia.   
     
     
         2 . The method of  claim 1 , further comprising determining a friction coefficient based on the set dwell speed, wherein the determined mass moment of inertia is further based on the friction coefficient. 
     
     
         3 . The method of  claim 2 , wherein the determined friction coefficient is further based on a predetermined damping coefficient. 
     
     
         4 . The method of  claim 2 , wherein the determined mass moment of inertia is further based on a predetermined damping coefficient. 
     
     
         5 . The method of  claim 2 , wherein the determined friction coefficient is further based on the calculated torque value. 
     
     
         6 . The method of  claim 1 , wherein determining a mass moment of inertia occurs during accelerating the basket. 
     
     
         7 . The method of  claim 6 , further comprising repeating determining a mass moment of inertia during accelerating the basket. 
     
     
         8 . The method of  claim 1 , wherein calculating the torque value comprises utilizing a set torque regression equation comprising a rotational speed value, electrical current value, an electrical voltage value, or an electrical power value. 
     
     
         9 . The method of  claim 1 , wherein calculating the torque value comprises utilizing a set torque regression equation comprising
     T =( A*ω   2   *I   2 )+( B*I   2 )+( C*ω   2 )+( D*ω*I )+( E*I )+( F*ω )+ G      wherein T represents the torque value,   wherein A, B, C, D, E, F, and G represent predetermined coefficients of the washing machine appliance,   wherein ω represents an associated rotational speed of the basket, and   wherein I represents a measured electrical current at the motor.   
     
     
         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;   a motor in mechanical communication with the basket to selectively rotate the basket within the tub; and   a controller in operative communication with the valve and motor, the controller configured to initiate an operative cycle comprising
 spinning the basket at a set dwell speed, 
 calculating a torque value based on the set dwell speed, 
 accelerating the basket to an elevated rotational speed, 
 determining an acceleration rate during accelerating the basket, 
 determining a mass moment of inertia based on the calculated torque value and the determined acceleration rate, and 
 adjusting acceleration of the basket according to the determined mass moment of inertia. 
   
     
     
         11 . The washing machine appliance of  claim 10 , wherein the operative cycle further comprises
 determining a friction coefficient based on the set dwell speed, wherein the determined mass moment of inertia is further based on the friction coefficient.   
     
     
         12 . The washing machine appliance of  claim 11 , wherein the determined friction coefficient is further based on a predetermined damping coefficient. 
     
     
         13 . The washing machine appliance of  claim 11 , wherein the determined mass moment of inertia is further based on a predetermined damping coefficient. 
     
     
         14 . The washing machine appliance of  claim 11 , wherein the determined friction coefficient is further based on the calculated torque value. 
     
     
         15 . The washing machine appliance of  claim 10 , wherein determining a mass moment of inertia occurs during accelerating the basket. 
     
     
         16 . The washing machine appliance of  claim 15 , wherein the operative cycle further comprises
 repeating determining a mass moment of inertia during accelerating the basket.   
     
     
         17 . The washing machine appliance of  claim 10 , wherein calculating the torque value comprises utilizing a set torque regression equation comprising a rotational speed value, electrical current value, an electrical voltage value, or an electrical power value. 
     
     
         18 . The washing machine appliance of  claim 10 , wherein calculating the torque value comprises utilizing a set torque regression equation comprising
     T =( A*ω   2   *I   2 )+( B*I   2 )+( C*ω   2 )+( D*ω*I )+( E*I )+( F*ω )+ G      wherein T represents the torque value,   wherein A, B, C, D, E, F, and G represent predetermined coefficients of the washing machine appliance,   wherein ω represents an associated rotational speed, and   wherein I represents a measured electrical current at the motor.