cob3-5 has a powerball tray with 3 joints: tray_1_link, tray_2_link and tray_3_link, the reference positions are:

	<property name="tray_1_ref" value="${def_tray_1_ref+offset_tray_1_ref}"/>
	<property name="tray_2_ref" value="${def_tray_2_ref+offset_tray_2_ref}"/>
	<property name="tray_3_ref" value="${def_tray_3_ref+offset_tray_3_ref}"/>