System for additive manufacturing processes and related control method
A system for additive manufacturing processes includes an anthropomorphic robot, an extruder mounted on the robot, sensors for detecting a plurality of parameters related to an additive manufacturing process, means for regulating the state of a material extruded from the extruder and a control unit configured to control an extruder path; the control unit is configured to determine the extruder path and/or the deposition strategies of the material according to at least two parameters detected by the sensors.
1 . A system for additive manufacturing processes, comprising:
a robot, the robot being an anthropomorphic industrial type of robot;
an extruder configured to be mounted on said robot;
a first temperature sensor and a first position sensor, said first temperature sensor configured to measure temperature of extruded material, and said first position sensor configured to measure dimensional properties of extruded material;
a plurality of regulators of a material extruded from said extruder;
a control unit configured to control a path of the extruder and to determine the path of the extruder based on measurements by said first temperature sensor and by said first position sensor;
wherein:
the control unit comprises measurement and/or control means in a closed loop for measuring and/or controlling the mechanical properties of the material that has just been extruded and is configured to acquire information from at least one area surrounding the material that has just been extruded, the control unit being also configured to determine the at least one surrounding area based on a temperature and a dimensional property measured by said first temperature sensor and by said first position sensor; and
wherein the control unit is configured to, during extrusion, adjust:
height of the extruder to obtain a compression between layers of said material extruded from said extruder based on the measured dimensional property of the first position sensor,
tolerance of said compression on a height corresponding to an ideal compression between the layers based on a suitable temperature detected by the temperature sensor,
advancement speed of said extruder on a height corresponding to an ideal compression between the layers based on a suitable temperature detected by the first temperature sensor, and
a flow rate of the material which is extruded on a height corresponding to an ideal compression between the layers based on a suitable temperature detected by the first temperature sensor; and
wherein said first temperature sensor is at least one of the following: an infrared sensor, a thermal camera, a pyrometer and a laser sensor.
2 . The system according to claim 1 , wherein the first temperature sensor takes a temperature measurement on at least one of the following: a cross section, a lower portion and an upper portion of the material exiting the extruder.
3 . The system according to claim 1 , wherein said first position sensor is at least one of the following:
a triangulation laser scanner, laser pointer, confocal sensor, stereoscopy, time-of-flight cameras, capacitive, inductive, photoelectric or ultrasonic sensors and probes with force-sensing resistor sensors.
4 . The system according to claim 1 , wherein said first position sensor takes a dimensional measurement on at least one of the following: a cross section, a lower portion and an upper portion of the material exiting the extruder.
5 . The system according to one claim 1 , wherein the system for additive manufacturing processes comprises a compaction element configured to act upon the material exiting the extruder.
6 . The system according to claim 1 , wherein said regulators are temperature regulators configured to change the temperature of the material that has just been extruded, based on a position and a temperature respectively detected by said first temperature sensor and by said first position sensor.
7 . The system according to claim 1 , wherein the first position sensor and the first temperature sensor are positioned on a support configured to be mounted on the extruder of the system for additive manufacturing processes.
8 . The system according to claim 7 , wherein said support is mounted in the proximity of the nozzle of the extruder.
9 . The system according to claim 1 , wherein said measurement and/or control means in a closed loop are also suitable for detecting and/or controlling a cooling gradient and/or at least one chemical or physical parameter correlated with a crystallization processes of the material that has just been extruded.
10 . The system according to claim 9 , wherein said measurement and/or control means in a closed loop comprise a Raman-effect sensor and/or an “FTIR”-type spectroscopic sensor.
11 . The system of claim 1 , wherein the extruder comprises a nozzle configured to extrude the material being extruded, wherein the system is configured so the first temperature sensor is in front of the nozzle with respect to an advancement direction of the extruder, and wherein the system is configured to use the first temperature sensor to determine whether the temperature of said material that has already been deposited is within a desired temperature range.
12 . The system of claim 11 , wherein it further comprises a second temperature sensor, and wherein the system is configured so that the second temperature sensor is behind the nozzle with respect to an advancement direction of the extruder, and wherein the system is configured to use the second temperature sensor to determine whether the temperature of the material being extruded is within a desired temperature range.
13 . The system of claim 1 , wherein the extruder comprises a nozzle configured to extrude the material being extruded, wherein the system is configured so that the first position sensor is in front of the nozzle with respect to an advancement direction of the extruder and so that the first position sensor is configured to detect dimensions of said material that has already been deposited.
14 . The system of claim 13 , wherein it further comprises a second position sensor, and wherein the system is configured so that the second position sensor is behind the nozzle with respect to an advancement direction of the extruder and so that the second sensor is configured to monitor an extrusion geometry of the material being extruded onto said material that has already been deposited.
15 . A system for additive manufacturing processes, comprising:
a robot, the robot being an anthropomorphic industrial type of robot;
an extruder configured to be mounted on said robot;
a first temperature sensor and a first position sensor, said first temperature sensor configured to measure temperature of extruded material, and said first position sensor configured to measure dimensional properties of extruded material;
a plurality of regulators of a material extruded from said extruder;
a control unit configured to control a path of the extruder and to determine the path of the extruder based on measurements by said first temperature sensor and by said first position sensor;
wherein:
the control unit comprises measurement and/or control means in a closed loop for measuring and/or controlling the mechanical properties of the material that has just been extruded and is configured to acquire information from at least one area surrounding the material that has just been extruded, the control unit being also configured to determine the at least one surrounding area based on a temperature and a dimensional property measured by said first temperature sensor and by said first position sensor; and
wherein the control unit is configured to, during extrusion, adjust:
height of the extruder to obtain a compression between layers of said material extruded from said extruder based on the measured dimensional property of the first position sensor,
tolerance of said compression on a height corresponding to an ideal compression between the layers based on a suitable temperature detected by the first temperature sensor;
wherein said first temperature sensor is at least one of the following: an infrared sensor, a thermal camera, a pyrometer and a laser sensor, said first temperature sensor taking a temperature measurement on at least one of the following: a cross section, a lower portion and an upper portion of the material exiting the extruder; and
wherein said first position sensor is at least one of the following: a triangulation laser scanner, laser pointer, confocal sensor, stereoscopy, time-of-flight cameras, capacitive, inductive, photoelectric or ultrasonic sensors and probes with force-sensing resistor sensors, said first position sensor taking a dimensional measurement on at least one of the following: a cross section, a lower portion and an upper portion of the material exiting the extruder.