US 12,459,202 B2
Flow rate control in extrusion deposition process
Andrew John Stewart Edwards, North Somerset (GB); and Frank A. McKiel, Jr., Colorado Springs, CO (US)
Assigned to 3D SYSTEMS, INC., Rock Hill, SC (US)
Filed by 3D Systems, Inc., Rock Hill, SC (US)
Filed on Jan. 14, 2025, as Appl. No. 19/020,228.
Claims priority of provisional application 63/622,800, filed on Jan. 19, 2024.
Prior Publication US 2025/0236071 A1, Jul. 24, 2025
Int. Cl. B29C 64/343 (2017.01); B29C 64/393 (2017.01); B33Y 10/00 (2015.01); B33Y 40/00 (2020.01); B33Y 50/02 (2015.01)
CPC B29C 64/343 (2017.08) [B29C 64/393 (2017.08); B33Y 10/00 (2014.12); B33Y 40/00 (2014.12); B33Y 50/02 (2014.12)] 12 Claims
OG exemplary drawing
 
1. A method, in a robotic system for forming a solid object by depositing layers of an extruded material in a controlled pattern according to a digital model of the solid object, for controlling fill proportion of the layers being deposited comprising:
for at least a portion of one first designed layer for which a fill proportion is to be controlled to a specific value, depositing, using a first flow rate expressed as a volume of discharge per unit of lateral motion, a plurality of adjacent discharges to form a first deposited layer of material in fulfillment of at least the first designed layer;
performing at least one distance measurement on the first deposited layer to obtain observed profile data of the first deposited layer;
from the profile data, calculating at least one difference value between an expected profile, according to the first designed layer, and the observed profile data;
providing the at least one difference value as an argument to a control algorithm that determines a second flow rate that is offset from the first flow rate by at least a first factor times the at least one difference value and of a second factor times a cumulative value of difference values measured for multiple layers; and
for at least a portion of one second designed layer for which a fill proportion is to be controlled, depositing, using the second flow rate of discharge per unit of lateral motion, a plurality of adjacent discharges to form a second deposited layer of material in fulfillment of the second designed layer;
while forming the solid object, also depositing layers of the extruded material to form a height reference structure;
performing at least one distance measurement on the height reference structure to obtain observed profile data that is representative of the first deposited layer; and
using the at least one distance measurement on the height reference structure in calculating the second flow rate of discharge per unit of lateral motion.