Object holder for a direct-to-object printer

A direct-to-object print system for printing on a surface of an object, the direct-to-object print system comprising:

• at least one printhead configured to eject marking material on to a surface of an object;
• a support member positioned parallel to a plane formed by the printhead;
• an object holder comprising:
• a shuttle mount configured to slideably traverse the support member, a first side wall and a second side wall disposed on the shuttle mount in a direction perpendicular to a direction of travel along the support member and perpendicular to the plane formed by the at least one print head;
• at least one collapsible membrane attached to the shuttle mount, the membrane forming an airtight sack filled with granules, the membrane collapses at least partially around an object when a volume of air is withdrawn from the membrane the first side wall and the second side wall forming a shape around the membrane that contains the object on the membrane;
• and
• a pump connected to the membrane, the pump withdrawing a volume of air from the membrane causes the membrane to collapse, the vacuum-packed granules inside the collapsed membrane conform to a shape of the object thereby securing the object to the shuttle mount;
• and
• a controller configured to cause the printhead to eject marking material onto the object held by the object holder as the object passes the printhead.