Abstract: A method and apparatus is disclosed for grading the surface of generally apherical fruit according to surface characteristics such as color and blemish. The fruit are moved in single file past a scanning camera while being rotated about a transverse horizontal axis. Reflectivity data in three separate wavelength bands is collected for a series of scans of each article of fruit, and this data is processed to eliminate all duplicative data arising from the fruit's rotation. Color ratio signals based on the remaining reflectivity data are then utilized to grade the fruit according to their surface color and degree of blemish.

Abstract: A variable speed induction motor drive system operating at a leading power factor. A prescribed reactive power is coupled to the motor's rotor, to permit line commutation of an inverter supplying the motor's stator, and to permit the inverter to be supplied by a substantially constant dc link voltage.