CN204036852U

CN204036852U - A kind of 3D printer controller

Info

Publication number: CN204036852U
Application number: CN201420433396.4U
Authority: CN
Inventors: 覃琴
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-08-04
Filing date: 2014-08-04
Publication date: 2014-12-24
Anticipated expiration: 2024-08-04

Abstract

The utility model proposes a kind of 3D printer controller, described 3D printer controller comprises micro-control unit MCU and FPGA; Described micro-control unit MCU is used for the control of motion control calculating and man-machine interface, is connected be used for man-machine interaction external interface or external equipment by data wire; Described FPGA is used for the generation of sequential logic and the control to printing device, is connected the interface or equipment that are used for Print Control by data wire.For 3D printing technique, the utility model improves machining accuracy relative to existing, promotes process velocity, and improves working (machining) efficiency.

Description

A kind of 3D printer controller

Technical field

The utility model relates to electro-mechanical arts, particularly relates to a kind of 3D printer controller.

Background technology

3D printer, i.e. a kind of machine of RP technique, it is based on a kind of mathematical model file, uses special wax material, powdery metal or plastics etc. can jointing material, is carried out the technology of constructed object by the mode successively printed.Usually be used to modeling or the direct manufacture for some products in the field such as Making mold, industrial design.

3D printer RepRap popular at present, it has the of self-replication capacity to a certain degree, can print himself (plastics) assembly of major part.RepRap is the abbreviation of (replicating rapid prototyper).This prototype various data from software to hardware is all free and increase income.

But it is slow that the following problem of existing increase income 3D printer REPPAP and derivative type thereof: process velocity is slow: REPPAP and derivative type thereof print process velocity, the object within its processing one 1 cubic decimeter needs just can complete for 4-6 hour; Printing precision is low, has obvious lamination vestige; Linking between motion is not tight, causes equipment to impact serious; On software, speed planning is not had to the motion between instruction, easily causes that elliptical gear, equipment are shaken, workpiece crosses the problems such as processing; The driving force of step actuator is more weak (below 1.5A drive current), cannot drive printhead high-speed motion; Control system complex circuit, poor reliability; Software operation is complicated, and Consumer's Experience is poor.

The existing 3D print control unit usually direct timer by Arduino control panel of increasing income sends out the control that Pulse Width Control motor driver realizes 3D printer, but it has following shortcoming: it is low that timer sends pulse frequency, therefore motor speed cannot improve, thus affects working (machining) efficiency; There is larger time slot between instruction and instruction, therefore cause motor movement to there are vibrations, affect machining accuracy, under serious conditions, will step be lost; Owing to only having USB from machine interface (this interface is modeled into a serial ports at PC, instead of is modeled to USB flash disk), therefore to copy files on board and must, by the assistant software operation on PC, use complicated; Cannot carry out multi-machine operation, namely a computer controls the telework of multiple stage 3D printer, is not suitable for large-scale processing and uses; Scalability is strong, most multi-band 2 printheads.

Summary of the invention

For the problems referred to above that prior art exists, the utility model proposes a kind of 3D printer controller, to solve the problem.

Solution of the present utility model is as follows:

A kind of 3D printer controller, described 3D printer controller comprises micro-control unit MCU and FPGA; Described micro-control unit MCU is used for the control of motion control calculating and man-machine interface, is connected be used for man-machine interaction external interface or external equipment by data wire; Described FPGA is used for the generation of sequential logic and the control to printing device, is connected the interface or equipment that are used for Print Control by data wire.

Preferably, described micro-control unit MCU is the STM32 chip of STMicw Electronics.

Preferably, the external interface that connects of described micro-control unit MCU or external equipment are USB interface, network interface, LCD interface, blue tooth interface, universal asynchronous receiving-transmitting coffret URAT, SD card interface; The external interface that described micro-control unit MCU connects or external equipment also comprise warning device.

Preferred further, described connection LCD interface is for connecting LCD control panel, and described LCD control panel is provided with control button.

Preferably, the interface that connects of described FPGA or equipment are stepper motor driving circuit, extruder head motor, temperature control interface, servomotor interface and compiler feedback.

Preferred further, described extruder head motor is 3 or 4.

Preferred further, described encoder feedback is 2 road input interfaces.

The utility model has the following advantages:

On the basis of not obvious increase cost, on existing type by by every NC technology application in 3D print system, improve machining accuracy, promote process velocity, and improve working (machining) efficiency.

Ease for use is high, motion controller can be used as USB flash disk and uses, movement velocity is fast, high-speed pulse output can be supported, upgrading is simple, extensibility strong, there is exclusive reduction of speed pause function, instruction is connected and more steps up to urge, not lose step at a high speed, there is exclusive speed look forward to the prospect and trajectory planning motion control function.

The utility model has exclusive speed prediction and trajectory planning motion control function, the prediction of the speed of advanced person and trajectory planning techniques are applied to 3D to be printed in motion control, make the present speed of printhead in any case can reach the maximal rate of current permission and not produce impact, while significantly can improving working (machining) efficiency, crudy is carried on as usual.

Accompanying drawing explanation

Fig. 1 is 3D printer controller hardware block diagram of the present utility model.

Fig. 2 is exercise data handling process of the present utility model.

Detailed description of the invention

Do to illustrate in detail, intactly further to the utility model below in conjunction with embodiment and accompanying drawing.

The utility model 3D printer controller adopts the Duo-Core Architecture structure of micro-control unit MCU (Micro Control Unit) and FPGA (Field Programmable Gate Array).Micro-control unit MCU is used for the control of motion control calculating and man-machine interface, and FPGA is used for the generation of sequential logic and the control to printing device.The framework of such double-core makes whole system divide the work clearly, thus improves the real-time of whole system, and making to print stationarity increases, and precision improves; On software, introduce trajectory planning algorithm simultaneously, working (machining) efficiency is increased substantially.In addition, be integrated with network controller and bluetooth in systems in which, making it can be mutual with miscellaneous equipment easily, especially with mobile phone or computer mutual.

Figure 1 shows that 3D printer controller hardware block diagram of the present utility model.

As shown in Figure 1, the utility model mainly comprises the double-core product architecture of micro-control unit MCU and FPGA, and here micro-control unit is preferably the STM32 chip of STMicw Electronics.

STM32 is absorbed in man-machine interaction and motion control related algorithm and operation.Known by Fig. 1: STM32(micro-control unit MCU) be connected by data wire with FPGA, for the transmission of data.For man-machine interaction, STM32 chip connects a series of external interface or external equipment by data wire.These external interfaces or external equipment are used for man-machine interaction, include but not limited to: USB interface, network interface, LCD interface, blue tooth interface, universal asynchronous receiving-transmitting coffret URAT(Universal Asynchronous Receiver/Transmitter), SD card interface, simultaneously in order to the security performance that 3D printer controller improves, STM32 chip is also connected to warning device.

The network interface that STM32 draws and blue tooth interface.Preferably, network interface is 100M high speed network interfaces here, and network enabled connects 3D printer controller motion control card.Can long-range connection computer by network interface, realize remote printing or wireless printing, both can print by a computer monitor multiple stage 3D printer simultaneously, also can connect by multiple stage 3D printer, realize networking and print.Blue tooth interface supports extendible bluetooth 4.0 function simultaneously, and bluetooth supports all motion control commands, and therefore user by mobile phone with after the pairing of 3D printer, can operate 3D printer with mobile phone.

STM32 connects LCD interface for connecting LCD control panel, is provided with control button at LCD control panel simultaneously.Preferably, arrange three and control button.These three buttons are upper and lower button respectively and confirm button, by these three buttons, we can each interface of switchable liquid crystal, and select and operate the various function of 3D printer, therefore we just can not need to be connected computer and controller by USB this LCD control panel and control button, and by computer manipulation controller.By LCD control panel with control button, computer and miscellaneous equipment can not be connected, can direct offline operation.

STM32 is provided with USB interface.By USB interface directly to the upgrading of 3D printer controller, and can not worry to upgrade unsuccessfully, even if failure also can be upgraded again.Such upgrading is simple.Therefore domestic consumer can upgrade up-to-date firmware program at any time, and does not worry that 3D printer controller is upgraded and unsuccessfully cause 3D printer not use.And current 3D printer controller is on the market when upgrading unsuccessfully, genuine can only be returned, upgraded by the specific purpose tool of genuine.

FPGA is used for the generation of sequential logic and the control to printing, the SECO part that requirement of real-time is high all completes in FPGA, this can ensure that the high real-time of whole system, the quality time saving again MCU in a large number makes MCU can be used for complicated trajectory planning algorithm, this makes print speed faster, runs more smooth and steady.3D printer adapter generally adopts chip microcontroller on the market at present, linking between instruction and instruction relies on interrupt handling routine, linking between a upper movement instruction and next movement instruction needs the delay time of more than 1MS, therefore can produce in high-speed motion and impacts and cause motor to lose step; And the utility model adopts FPGA, realize buffering area in FPGA inside, next movement instruction can be performed immediately within a clock after a upper instruction executes, within the convergence time between instruction can accomplish 0.1 microsecond.Like this, the utility model instruction linking more steps up to urge, and does not lose step at a high speed.

Known by Fig. 1: FPGA is by the external a series of interface of data wire or equipment.These interfaces or the control of equipment for printing, include, but are not limited to stepper motor driving circuit, extruder head motor, temperature control interface, servomotor interface and compiler feedback.

The external stepper motor driving circuit of FPGA.Stepper motor driving circuit draws step motor control interface for controlling the wire of X, Y, Z axis motor movement and each printhead.

The external extruder head motor of FPGA.FPGA is by the external multiple extruder head motor of pulse direction output interface easily extensible of multichannel.Extruder head motor is preferably 3 or 4, and in Fig. 1, extruder head motor is 3.Relative to existing technology, 3D printer controller of the present utility model has absolute predominance when the 3D printer of use 3 or 4 extruder heads.

FPGA external temperature control interface.FPGA carries out temperature control by external temperature control interface, and 3D printer controller reads temperature value automatically, and utilizes the peculiar advantage of FPGA to produce the temperature that PWM controls extruder head and hott bed in real time, makes as STM32 saves the plenty of time; Thus can be used for the calculating of complicated trajectory planning and speed prediction control algolithm the CPU time of preciousness, this finally makes stationarity better, and process velocity is higher.

The external servomotor interface of FPGA and compiler feedback.FPGA provides the control interface of servomotor and corresponding encoder feedback interface, more high performance servomotor is adopted by the control interface of servomotor, can improve process velocity and machining accuracy further, and print speed can be made faster, print quality is higher.The utility model provides 2 tunnel encoder feedback input interfaces, can connect the equipment such as handwheel and photoelectric encoder when high-precision applications, and therefore in the system using Serve Motor Control 3D printer, performance is better, has absolute predominance.

Existing 3D printer adapter, usually adopt timer to send out pulse, frequency is lower than 50KHZ, and when speed is higher, then processor speed does not catch up with.Because the utility model adopts FPGA to complete the hardware time order function of motion control, therefore every axle output pulse can reach 0-2MHZ, far away higher than other 3D printer adapters on market.Therefore speed can be accomplished very fast.Stepper motor driver general at present can support the Puled input of 200KHZ, and AC servo machinery driving device can reach the Puled input supporting about 2MHZ.

3D printer controller of the present utility model can be used as USB flash disk and uses.After the utility model motion controller is connected by USB with PC, in PC, 3D printer controller can be shown as 2 USB devices, one is that (serial equipment of printer is exactly 3D printer for the serial equipment of the utility model printer, it can be interpreted as the performance of 3D printer in computer equipment manager, there is this serial equipment, computer is just known has a 3D printer to be connected to computer now, then computer can operate this serial equipment by program, namely operate this printer), a moveable magnetic disc can be demonstrated in computer simultaneously, processed file directly copies in this mobile disk by user can start processing, fast very convenient, make can processed file is copied directly on motion control card when not installing any software and driver, and perform.Also can by the compatible multiple print software on the market of the mode of serial equipment, user can by the mode of 3D print software and the utility model mutual.Said process, after connecting computer like a normal printer by USB, computer can be identified as 2 equipment, one is printer, one is USB flash disk, at this time document copy also can be realized printing function to USB flash disk, clicks print button and also can realize printing function inside WORD.

Be illustrated in figure 2 exercise data handling process of the present utility model.

User obtains 3D graphic file by various means, by this file of special-purpose software pretreatment on computer and mobile phone, then by this file by various mode (bluetooth, WIFI, USB flash disk, SD card, USB is from mouth) to be a kind ofly sent in the 3D print control unit of 3D printer, restart processing.3D print control unit to receive after file by a series of and processing mode, file translations is become movement instruction and control instruction, then carries out a series of optimization process to instruction, then data is sent in FPGA and exports final motor control signal; 3D print control unit will have control printhead and hott bed temperature in real time according to instruction simultaneously;

Exercise data handling process of the present utility model comprises the steps: as shown in Figure 2

Step S10, starts, and starts here to be 3D print control unit of the present utility model start power up or the process for 3D print control unit preparation;

Step S11, obtains file, specifically refers to: user passes through to obtain 3D graphic file, by after special-purpose software pretreatment on computer and mobile phone, then be sent in 3D printer by this file, load mode can pass through bluetooth, WIFI, USB flash disk, SD card, USB etc. realize any one;

Step S12, resolution file, resolves the file that step S11 obtains, and resolves to corresponding motion and control instruction;

Step S13, accurate microcommand is resolved, and the file that step S12 resolves is resolved the microcommand that is as the criterion further;

Step S14, trajectory planning, refers to the process of the accurate microcommand that step S13 is resolved being carried out further microinstruction operation;

Reduction of speed pause function or step is also comprised: be specially in track planning step:

Step S141, setting acceleration;

Step S142, judges whether when receiving pause instruction;

Step S143, abovementioned steps S142 judge to receive pause instruction, stop after present instruction reduction of speed to 0 by the acceleration of step S141 setting;

Step S144, judges whether when receiving recovery instruction;

Step S145, if abovementioned steps S144 judges to receive recovery instruction, returns to normal speed by the acceleration of step S141 setting by movement velocity;

3D on the market prints when motion control snaps fit onto pause instruction and by direct for speed reduction of speed to 0, can produce like this and impact and cause motor to lose step.

Step S15, data are carried out processing the data being treated to FPGA and can using by speed prediction process;

Speed prediction process is specifically further comprising the steps of:

Step S151, determines the wedge angle speed of extruder head movement locus;

Determine the wedge angle speed of extruder head movement locus, after measuring and calculating analysis being carried out to the figure that will print specifically by certain algorithm, draw the wedge angle speed of extruder head movement locus.

Step S152, determines the peak acceleration of extruder head motion reduction of speed before the wedge angle speed of step S151;

Step S153, determines the maximum permission speed of extruder head motion each point before the wedge angle speed of step S151;

Step S154, calculates the rate curve of extruder head according to above-mentioned steps.

The processing extruder head of printer needs at X, Y, Z cartesian space is according to the shape high-speed motion of workpiece, scrambling due to workpiece causes the movement locus scrambling of extruder head, extruder head movement locus has a lot of wedge angles, and extruder head itself has certain inertia, this just require extruder head sharp corner must reduction of speed (extruder head is minimal point in the speed of each track sharp corner, but not necessarily smallest point), this speed can not lower at once, need slowly to reduce by certain acceleration in advance, this just needs the maximal rate being calculated each permission by certain algorithm dynamically, simultaneously calculate a rational rate curve according to the maximum permission speed of each point and peak acceleration, ensure speed can be kept the highest when each tracing point does not exceed maximum permission speed, namely speed prediction solves this problem.

In step S14 and step S15, use advanced speed prediction and trajectory planning techniques, make the present speed of printhead in any case can reach the maximal rate of current permission and not produce impact, while significantly can improving working (machining) efficiency, crudy is stablized.

Step S16, is sent to FPGA, and FPGA carries out moving interpolation according to the actual conditions printed and exports control print procedure.

Step S17, after the print procedure of above-mentioned steps S17 completes, waits for and terminating.

Step S11 to step S15 carries out at micro-control unit MCU, for the control of motion control calculating and man-machine interface.And step S16 carries out in FPGA, FPGA operates the generation for sequential logic to the instruction that micro-control unit MCU sends.Above-mentioned steps in the operation respectively of micro-control unit MCU and FPGA, whole system to be divided the work clear and definite, thus improve the real-time of whole system, making to print stationarity increases, and precision improves.

Following step can also be comprised after step s 12 simultaneously:

Step S18, accepts temperature control instruction, refers to the dependent instruction accepted about temperature control after step S12 resolution file;

Step S19, temperature control, in FPGA by instruction morphing for the temperature control of step S18 be sequential logic signal, by temperature control interface output carry out temperature control;

Step S20, after the process of above-mentioned steps S19 completes, waits for and terminating.

The effect of step S18 to step S20 is: 3D print control unit, carrying out print job while, will have according to instruction and control printhead and hott bed temperature in real time.

The utility model patent is independent of 3D print system design of abroad increasing income, and the main purpose of design is the problem solving existing increase income 3D printer REPPAP and derivative type thereof.The utility model has the following advantages: the research and development of the processing technology that the utility model main research reactor stacked 3D printer is correlated with and control system, by improving system module integrated level, and introduce speed look-ahead algorithm, trajectory planning algorithm, the hard interpolation technique of high-performance FPGA etc.; On the basis of not obvious increase cost, on existing type by by every NC technology application in 3D print system, improve machining accuracy, promote process velocity, and improve working (machining) efficiency.Ease for use is high, motion controller can be used as USB flash disk and uses, movement velocity is fast, high-speed pulse output can be supported, upgrading is simple, extensibility strong, there is exclusive reduction of speed pause function, instruction is connected and more steps up to urge, not lose step at a high speed, there is exclusive speed look forward to the prospect and trajectory planning motion control function.The utility model has exclusive speed prediction and trajectory planning motion control function, the prediction of the speed of advanced person and trajectory planning techniques are applied to 3D to be printed in motion control, make the present speed of printhead in any case can reach the maximal rate of current permission and not produce impact, while significantly can improving working (machining) efficiency, crudy is carried on as usual.

Those skilled in the art will readily understand; the foregoing is only better enforcement of the present utility model; do not limit the utility model, all do within spirit of the present utility model and principle any amendment, equivalent to replace and improvement etc., all should within protection domain of the present utility model.

Claims

1. a 3D printer controller, is characterized in that: described 3D printer controller comprises micro-control unit MCU and FPGA; Described micro-control unit MCU is used for the control of motion control calculating and man-machine interface, is connected be used for man-machine interaction external interface or external equipment by data wire; Described FPGA is used for the generation of sequential logic and the control to printing device, is connected the interface or equipment that are used for Print Control by data wire.

2. 3D printer controller as claimed in claim 1, is characterized in that: described micro-control unit MCU is the STM32 chip of STMicw Electronics.

3. 3D printer controller as claimed in claim 1 or 2, is characterized in that: the external interface that described micro-control unit MCU connects or external equipment are USB interface, network interface, LCD interface, blue tooth interface, universal asynchronous receiving-transmitting coffret URAT, SD card interface; The external interface that described micro-control unit MCU connects or external equipment also comprise warning device.

4. 3D printer controller as claimed in claim 3, is characterized in that: described connection LCD interface is for connecting LCD control panel, and described LCD control panel is provided with control button.

5. 3D printer controller as claimed in claim 1, is characterized in that: the interface that described FPGA connects or equipment are stepper motor driving circuit, extruder head motor, temperature control interface, servomotor interface and compiler feedback.

6. 3D printer controller as claimed in claim 5, is characterized in that: described extruder head motor is 3 or 4.

7. 3D printer controller as claimed in claim 5, is characterized in that: described compiler is fed back to 2 road input interfaces.