Abstract: An automated order fulfillment system and mobile robot are disclosed, where the mobile robot includes a compliant drive for moving between levels of a multilevel storage structure. In one example, the compliant drive comprises a drive shaft having splines configured to provide rotational play that prevents jamming of a vertical drive gear on the end of the shaft with a rack in a vertical track.

Abstract: In a process for condensing the vapor of a volatile liquid, such as vinyl chloride monomer, a gaseous mixture comprising the vapor of the volatile liquid and a non-flammable gas, such as nitrogen, is heat exchanged with a liquid refrigerant or vapor evolved therefrom, or both, the heat exchange being performed such that condensate of the vapor of the volatile liquid is produced at a directly or indirectly controlled temperature which is between the boiling point of the volatile liquid at atmospheric pressure and the boiling point of the refrigerant at atmospheric pressure and which is also between the boiling and freezing points of the volatile liquid at the prevailing pressure at which the condensate is formed, the non-flammable gas remaining uncondensed; the condensate is collected; the uncondensed gas is warmed to a temperature, and then vented to the atmosphere.