Claims:We Claim:
1. A method for real-time prediction of powder quantity in additive manufacturing, comprising the steps of:
measuring (301) real-time weight of powder in a hopper (101) in an apparatus (100), by a powder estimation module (201);
determining (302) real-time volume of build remaining for manufacturing, by a volume estimation module (202);
characterised in that
transmitting (303) the measured real-time weight, the determined real-time volume to a powder prediction module (203), by the powder estimation module (201) and the volume estimation module (202);
transmitting (304) parameters influencing quantity of the powder to the powder prediction module (203), by the apparatus (100); and
predicting (305) real-time weight of the powder required for manufacturing based on the measured real-time weight, the determined real-time volume and the parameters, by the powder prediction module (203).
2. The method as claimed in claim 1, wherein the powder estimation module (201) measuring the real-time weight of the powder using a plurality of load cells (104).
3. The method as claimed in claim 1, wherein the powder estimation module (201) including a proximity sensor for identifying level of powder below a threshold level inside the hopper (101); and
the powder prediction module (203) transmitting an alert to a user device based on the identified level of the powder below the threshold level for replenishing the powder in the hopper (101).
4. The method as claimed in claim 1, wherein the parameters influencing quantity of the powder include material of the powder, layer thickness, factor of over flow and speed of inert gas.
5. The method as claimed in claim 1, wherein the parameters are pre-entered in the apparatus by a user for manufacturing the build.
6. The method as claimed in claim 1, wherein the hopper (101) movable relative to a base (102) of the apparatus (100) corresponding to changes in quantity of the powder and facilitating the powder estimation module (201) for real-time measurement of the weight of the powder.
7. The method as claimed in claim 1, wherein the powder prediction module (203) predicts real-time weight of the powder required for completing manufacturing of the build at a given point of time by processing the received real-time weight of the powder, the real-time volume and the parameters and past data of quantity of powder consumption for manufacturing.
, Description:A METHOD FOR REAL-TIME PREDICTION OF POWDER QUANTITY IN ADDITIVE MANUFACTURING
FIELD
[0001] The embodiments herein generally relate to the field of additive manufacturing. More particularly, the disclosure relates to predicting quantity of powder required in an additive manufacturing system.
BACKGROUND AND PRIOR ART
[0002] Additive manufacturing is a process of depositing or joining materials, generally layer upon layer, to construct three dimensional objects from a digital 3D model data. Powder bed fusion is a technique of additive manufacturing process wherein metal powder is used as a raw material and an energy source, generally laser or electron beam, is used for melting the powder to form the required object.
[0003] The part to be manufactured is sliced into multiple layers based on a layer thickness chosen by the programmer for the specific print job. The machine controller commands a laser scanner system to selectively melt powder in the specified location and fuse it to previously formed layer of the respective parts based on the layer thickness.
[0004] Conventionally, the powder required for completing the manufacturing is pre-calculated logically, wherein slight miscalculations can lead to loss of production and valuable resource. The conventional methods do not provide the exact amount of powder required for the build. Generally, excess amounts of powder is used for uninterrupted manufacturing process. However, once the powder is used in the machine, irrespective of its consumption, the powder comes in contact with burnt particles or partially melted condensates causing the entire quantity of unused powder to be sieved before reuse. This is time consuming and reduces life of the powder.
[0005] Further, usage of lesser quantity of the powder interrupts the manufacturing process due to shortage. This causes a production downtime and unfavourable results on the printed parts due to waiting for prolonged periods of time wherein the entire part maybe rejected thereby wasting significant amounts of powder.
[0006] The absence of a robust powder estimation and a monitoring system leads to the above disclosed conventional situations. Inappropriate quantity of powder causes wastage of powder thereby increasing operational costs wherein, the raw material costs for the metal powders are between 10 to 25 times the cost of the equivalent ingots or solid blocks.
[0007] Therefore, there is a need for an optimized powder utilisation in additive manufacturing for increasing cost effectiveness and adaptability towards diversified applications. Moreover, there is a need for an automated method for predicting accurate quantity of powder required for completing the current print process.
OBJECTS
[0008] Some of the objects of the present disclosure are described herein below:
[0009] The main objective of the present disclosure is to provide a method for predicting quantity of powder in additive manufacturing.
[00010] Another objective of the present disclosure is to provide an accurate method of predicting real-time quantity of powder in additive manufacturing.
[00011] Still another objective of the present disclosure is to provide an automated method for predicting powder quantity.
[00012] Yet another objective of the present disclosure is to provide a method for predicting real-time powder quantity based on dynamic parameters.
[00013] The other objectives and advantages of the present disclosure will be apparent from the following description when read in conjunction with the accompanying drawings, which are incorporated for illustration of preferred embodiments of the present disclosure and are not intended to limit the scope thereof.
SUMMARY
[00014] In view of the foregoing, an embodiment herein provides a method for real-time prediction of powder quantity in additive manufacturing.
[00015] In accordance with an embodiment, the method comprises the steps of measuring real-time weight of powder in a hopper in an apparatus, by a powder estimation module, determining real-time volume of build remaining for manufacturing, by a volume estimation module, transmitting the measured real-time weight, the determined real-time volume to a powder prediction module, by the powder estimation module and the volume estimation module, transmitting parameters influencing quantity of the powder to the powder prediction module, by the apparatus and predicting real-time weight of the powder required for manufacturing based on the measured real-time weight, the determined real-time volume and the parameters, by the powder prediction module.
[00016] In accordance with an embodiment, the powder estimation module measuring the real-time weight of the powder using a plurality of load cells. In an embodiment, the powder estimation module including a proximity sensor for identifying level of powder below a threshold level inside the hopper and the powder prediction module transmitting an alert to a user device based on the identified level of the powder below the threshold level for replenishing the powder in the hopper.
[00017] In accordance with an embodiment, the parameters influencing quantity of the powder include material of the powder, layer thickness, powder over flow and speed of inert gas. In an embodiment, the parameters are pre-entered in the apparatus by a user for manufacturing the build.
[00018] In accordance with an embodiment, the hopper movable relative to a base of the apparatus corresponding to changes in quantity of the powder and facilitating the powder estimation module for real-time measurement of the weight of the powder.
[00019] In accordance with an embodiment, the powder prediction module predicts real-time weight of the powder required for completing manufacturing of the build at a given point of time by processing the received real-time weight of the powder, the real-time volume and the parameters and past data of quantity of powder consumption for manufacturing.
[00020] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[00021] The detailed description is set forth with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The use of the same reference numbers in different figures indicates similar or identical items.
[00022] Fig.1 illustrates a schematic of an apparatus of a powder storage unit 100 in additive manufacturing, according to an embodiment herein;
[00023] Fig.2 illustrates a block diagram of a system for real-time prediction of powder quantity in additive manufacturing, according to an embodiment herein; and
[00024] Fig.3 illustrates a flow chart of a method for real-time prediction of powder quantity in additive manufacturing, according to an embodiment herein.

LIST OF NUMERALS
100 - Storage unit apparatus
101 - Hopper
101a - Bottom portion
102 - Base
103 - Intermediate block
104 - Plurality of load cells
105 - Sensor mounting unit
201 - Powder estimation module
202 - Volume estimation module
203 - Powder prediction module
300 - Flow chart of a method for real-time prediction of powder quantity

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[00025] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[00026] As mentioned above, there is a need for an optimized powder utilisation in additive manufacturing for increasing cost effectiveness and adaptability towards diversified applications. In particular, there is a need for an automated method for predicting accurate quantity of powder. The embodiments herein achieve this by providing “A method for real-time prediction of powder quantity in additive manufacturing”. Referring now to the drawings, and more particularly to Fig.1 through Fig.3, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments.
[00027] Fig.1 illustrates a schematic of an apparatus of a powder storage unit 100 in additive manufacturing. In an embodiment, the apparatus 100 including a hopper 101, a base 102, an intermediate block 103, a plurality of load cells 104 and a sensor mounting unit 105.
[00028] In an embodiment, the hopper 101 is provided for storing a quantity of powder required for manufacturing a build. A volume of the hopper 101 is greater than a volume of powder required for manufacturing the complete build for holding the powder to ensure availability of the powder even after the manufacturing of the build is completed. When the hopper 101 is actuated, pre-determined amount of powder flows down to a powder dispensing unit.
[00029] In an embodiment, the base 102 is a foundation for mounting the hopper 101. The base 102 is mounted on the powder dispensing unit (not shown in fig). The powder dispensing unit conveys pre-determined amounts of powder from the hopper 101 to a powder spreading unit (not shown in fig). The powder dispensing unit is fixed to a powder spreading machine assembly. Removing the base 102 facilitates removal of the hopper 101 from the powder spreading machine assembly.
[00030] In an embodiment, the plurality of load cells 104 are connected to the hopper 101 for real-time measurement of weight of the powder. In an embodiment, type of the load cell includes but not limited to a shear beam load cell. In an embodiment, the load cells 104 are mounted on the base plate 102 below the hopper 101. The load cells 104 are connected to a junction box (not shown in fig) for summing the load and providing a single output of the total weight of the powder inside the hopper 101.
[00031] Every load cell 104 is calibrated to high accuracy levels for providing precise measurements of the weight of the powder available inside the hopper 101. Calibration process of the load cells 104 includes feeding accurately measured quantities of powder into the hopper 101, wherein the powder exert force on the load cells 104 and the generated electrical signal from the load cells 104 corresponding to the weight is measured.
[00032] The load cells 104 are deflected corresponding to an increase in weight or decrease in weight of the powder inside the hopper 101, thereby providing extent of change in the weight of the powder. The hopper 101 is mounted on the base 102 wherein the hopper 101 is movable and deflectable relative to the base 102, thereby facilitating the load cells 104 in measuring accurate real-time weight of the powder.
[00033] In a preferred embodiment, number of the load cells 104 is four and each load cell 104 can handle weight in excess of 300 Kgs depending on the volume of the hopper 101.
[00034] In an embodiment, the intermediate block 103 is attached to a bottom portion101a of the hopper 101 for facilitating as a passage for flow of the powder from the hopper 101 to an internal dispenser. The intermediate block 103 slides relative to the base 102, wherein the intermediate block 103 slides from the bottom portion 101a of the hopper 101 till the base 102. The relative sliding movement of the intermediate block 103 facilitates movement of the hopper 101 relative to the base 102 for precise measurement of weight of the powder by the load cells 104 due to deflections.
[00035] In an embodiment, the sensor mounting unit 105 is provided in the hopper 101 for mounting a sensor for identifying level of the powder inside the hopper 101 below a pre-defined level. In an embodiment, the sensor is a proximity sensor. The sensor is provided as a secondary feedback for backup, wherein on identifying level of the powder below the pre-defined level, the sensor transmits a feedback to a user device for replenishing powder to continue the manufacturing.
[00036] Fig. 2 illustrates a block diagram of a system of real-time prediction of powder quantity for additive manufacturing.
[00037] The system 200 includes a powder estimation module 201, a volume estimation module 202 and a powder prediction module 203.
[00038] In an embodiment, the powder estimation module 201 is electrically connected to the hopper 101 of the apparatus 100 for real-time estimation of weight of the powder in the hopper 101. The volume estimation module 202 is electrically connected to the apparatus 100. The apparatus 100, the powder estimation module 201 and the volume estimation module 202 are electrically connected to the powder prediction module 203.
[00039] In an embodiment, the powder estimation module 201 includes the load cells 104 and the sensors in the sensor mounting unit 105. The powder estimation module 201 measures the real-time weight of the powder in the hopper 101 and identifies level of powder lower than the predefined level inside the hopper 101. In an embodiment, the pre-defined level is set by a user. The measured real-time weight and the level of the powder identified below the threshold predefined level are transmitted to the powder prediction module 203. The movable hopper 101 and the powder estimation module 201 dynamically measure quantity of the powder throughout the manufacturing process of the build. The powder quantity is updated when clean powder is reloaded in the hopper 101 during the manufacturing process.
[00040] In an embodiment, the volume estimation module 202 estimates real-time volume of the build remaining to be manufactured through the manufacturing process. The estimated volume is transmitted to the powder prediction module 203.
[00041] In an embodiment, the powder prediction module 203 receives the measured real-time weight and the level of the powder identified below the threshold predefined level from the powder estimation module 201 and the estimated volume of the build remaining from the volume estimation module 202. The apparatus 100 transmits parameters influencing quantity of the powder for manufacturing the build to the powder prediction module 203. The parameters include but not limited to inert gas flow speed, overflow factor, spreadability of the powder, material, layer thickness and powder quality aspects.
[00042] A build chamber is provided for manufacturing the build by melting the powder using an energy source. An inert environment is provided in the build chamber for maintaining minimum levels of oxygen to prevent oxidisation leading to inferior quality of melt area in the build and to prevent explosion due to combustion. The inert environment is obtained by initial purging of inert gas into the build chamber. After the inert environment is achieved, a shield of recirculating inert gas is created above topmost powder layer melted and fused to the layer below. The speed of the inert gas flowing inside the build chamber is controlled for ensuring the inert gas does not blow away good powder from the build and does not retain burnt condensates in the build. The speed of the inert gas is adjusted based on the material type, particle size of the powder and layer thickness. Based on the speed of the inert gas, consumption of the powder changes, thereby changing the quantity of the powder.
[00043] A change in material of the powder influences the quantity of the powder occupying the hopper 101. Densities and flowability vary between different materials of the powder, thereby varying consumption of the powder for manufacturing the build. The weight of the powder varies corresponding to the powder consumption for the material for manufacturing plurality of parts in the build.
[00044] The parts embedded in the build are sliced into a plurality of layers using a software for printing the build layer after layer. The thickness of the layers of the build influences rate of powder consumption in the printing process.
[00045] Powder over flow is extra quantity powder added during the manufacturing to overcome the reduction in volume due to melting and to achieve uniform layer thickness of the build. The powder over flow is required when powder melts in selective regions of the build increasing the density of the material in that region and creating a void on top of the manufactured region. The extra powder added covers the void in a plurality of melted regions of previous layer of the build. The over flow factor is an extent of the powder over flow. The overflow factor is a predefined value that is changed by the user on a panel provided on the apparatus 100 during the manufacturing process. The overflow factor changes the total quantity of the powder required for manufacturing the build.
[00046] The parameters influencing the quantity of the powder include time dependent parameters and process dependent parameters. The time dependent parameters include real-time volume of build remaining for manufacturing, real-time weight of the powder in the hooper, the overflow factor and the speed of inert gas. The process dependent parameters include the layer thickness, particle size and material type which are not modifiable during the manufacturing of the build.
[00047] In an embodiment, the powder prediction module 203 processes the received real-time weight and the level of the powder identified below the threshold predefined level from the powder estimation module 201, the estimated volume of the build remaining from the volume estimation module 202 and the parameters influencing quantity of the powder from the apparatus 100.
[00048] The powder prediction module 203 includes past data of quantity of powder consumption for parameters received from the powder estimation module 201, the volume estimation module 202 and the apparatus 100. Based on a plurality of past data of the powder consumption, the powder prediction module 203 uses a multi-input non-linear black-box model for predicting the powder consumption for a given set of parameters.
[00049] In an embodiment, the powder prediction module 203 displays the real-time weight of the powder in the hopper 101 and the predicted weight of the powder required for manufacturing the build at a given time on a digital dial indicator.
[00050] In an embodiment, the powder prediction module 203 is connected to a user device for transmitting an alert when the sensor identifies the level of the powder in the hopper 101 below a threshold level. The alerts are transmitted based on a plurality of factors including but not limited to environment, time of the day and machine’s boundary conditions.
[00051] Fig. 3 illustrates a flow chart of a method for real-time prediction of powder quantity in additive manufacturing. The method includes measuring 301 real-time weight of the powder present in a hopper 101, by the powder estimation module 201 using a plurality of load cells 104. In an embodiment, the hopper 101 is movable relative to a base 102 of the apparatus 100 corresponding to changes in quantity of the powder. The movement of the hopper 101 facilitates real-time measurement of the weight of the powder by the plurality of load cells 104 provided in the powder estimation module 201.
[00052] In an embodiment, the powder estimation module 201 includes a proximity sensor for identifying level of powder below a threshold level inside the hopper 101 and transmits the identified level to the powder prediction module 203.
[00053] Next, the volume estimation module 202 determines 302 real-time volume of build remaining for manufacturing. The measured real-time weight, the determined real-time volume are transmitted 303 to the powder prediction module 203, by the powder estimation module 201 and the volume estimation module 202. The parameters influencing quantity of the powder are then transmitted 304 to the powder prediction module 203, by the apparatus 100. In an embodiment, the parameters influencing quantity of the powder include material of the powder, layer thickness, factor of over flow and speed of inert gas. The parameters are pre-entered in the apparatus 100 by a user for manufacturing the build.
[00054] The powder prediction module 305 processes the received real-time weight, the real-time volume and the parameters based on past data of quantity powder consumption.
[00055] Finally, the powder prediction module 203 predicts the real-time weight of the powder required for manufacturing based on the measured real-time weight, the determined real-time volume and the parameters.
[00056] In an embodiment, the powder prediction module 203 transmitting an alert to a user device based on the identified level of the powder below the threshold level for replenishing the powder in the hopper 101, as a secondary feedback for backup in addition to the prediction of the quantity of the powder.
[00057] A main advantage of the present disclosure is that the method provides prediction of quantity of powder for additive manufacturing.
[00058] Another advantage of the present disclosure is that the method provides accurate and real-time prediction of quantity of powder for additive manufacturing.
[00059] Still another advantage of the present disclosure is that the method prevents wastage of powder by accurately predicting real time weight of powder in additive manufacturing.
[00060] Yet another advantage of the present disclosure is that the method improves cost-effectiveness by reducing excess usage of quantity powder required for manufacturing.
[00061] Still another advantage of the present disclosure is that the method provides real-time monitoring of the quantity of powder consumption and predicts quantity of powder required for completing manufacturing of a build at a given point of time.
[00062] Yet another advantage of the present disclosure is that the method transmits an alert to a user on detecting reduced level of powder in the powder storage unit.
[00063] Still another advantage of the present disclosure is that the method provides real-time powder prediction based on past data and current data.
[00064] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.