Offline to online programming teaching system for robot arm trajectory and method thereof
Patent Information
- Authority / Receiving Office
- TW · TW
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-01-06
- Publication Date
- 2023-07-16
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
Figure TWG2TA000916043_001 
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Abstract
Description
[Technical Field]
[0001] A robotic arm trajectory teaching system and method, particularly a robotic arm trajectory teaching system and method that integrates offline programming and online programming. [Previous Technology]
[0002] In industrial production environments, the use of robotic arms for manufacturing is very widespread. Generally, robotic arms are manufactured along pre-programmed trajectories. However, programming the trajectory of a robotic arm to perform various complex postures and operations takes a lot of time and is quite difficult.
[0003] Specifically, for the polishing operation of the robotic arm in the production of wooden furniture, since wooden furniture usually has a relatively complex surface and a variety of components, it is necessary to set and record multiple operation positions for the robotic arm, which will increase the complexity of the robotic arm trajectory programming and reduce the effectiveness of trajectory programming.
[0004] In actual industrial production environments, programming of robotic arms is mainly divided into two different methods: offline programming and online programming. Specifically, online programming involves the user using a teaching device to remotely control the robotic arm to program its trajectory. Due to its ease of programming, most industrial production environments choose to use online programming to program the trajectory of the robotic arm.
[0005] Offline programming mostly involves the selection of 3D CAD models. 3D modeling is used to obtain the surface characteristics of objects, and the trajectory of the robotic arm is generated based on the surface characteristics of the objects. Offline programming can also verify the trajectory of the robotic arm through simulation, thereby reducing unnecessary errors during actual robotic arm operation.
[0006] Both offline and online programming have their advantages and disadvantages. Offline programming is suitable for high-precision trajectories of robotic arms, programming the robotic arm's trajectory to follow a straight line or track a specific motion pattern. In this case, offline programming will provide better performance than manually programming the robotic arm's trajectory using a teaching device. Relatively speaking, online programming is superior when it is necessary to determine the uniqueness and flexibility of the robotic arm's movements.
[0007] Generally, most industrial robotic arms are still used for repetitive, fixed tasks such as assembly, machining, welding, cutting, and polishing. For specialized processes like polishing, while offline programming can provide high-precision trajectories, these trajectories often lead to unexpected processing problems in actual production, such as inability to produce according to the high-precision trajectory or damage to the object caused by the high-precision trajectory. On the other hand, online programming allows for direct interaction and observation of the robotic arm's status while it is in contact with the object, effectively reducing errors in robotic arm operations. However, manually controlling the robotic arm using a teaching device requires excessive time to establish its trajectory.
[0008] In summary, it can be seen that the prior art has long suffered from the problems of unexpected processing difficulties when offline programming of robotic arm trajectories is applied to actual production, and the problem of online programming taking too much time to establish robotic arm trajectories. Therefore, it is necessary to propose improved technical means to solve this problem. [Summary of the Invention]
[0009] In view of the problems of unexpected processing difficulties arising from offline programming of robotic arm trajectories in actual production and the excessive time required for online programming to establish robotic arm trajectories in the prior art, the present invention discloses an offline-to-online programming teaching system and method for robotic arm trajectories, wherein:
[0010] The offline-to-online programming teaching system for robotic arm trajectories disclosed in this invention includes: a tactile force feedback device, a serial robotic arm, and a trajectory conversion and control device. The trajectory conversion and control device further includes: an offline trajectory programming module, a simulation module, an offline trajectory conversion module, and an online control module.
[0011] The tactile force feedback device transmits position and direction commands, receives guidance force information, and adjusts the position commands according to the guidance force information.
[0012] The serial robotic arm is equipped with a torque sensor and a polishing device. It controls the end position and end direction of the serial robotic arm according to the received position and direction commands, and transmits the controlled end position and end direction of the serial robotic arm.
[0013] The trajectory conversion and control device establishes a connection with the tactile force feedback device and the serial robotic arm respectively. It receives position and direction commands from the tactile force feedback device and transmits the position and direction commands to the serial robotic arm. It receives the end position and end direction of the serial robotic arm and transmits the guiding force information to the tactile force feedback device.
[0014] The offline trajectory programming module establishes a computer-aided design (CAD) model of the serial robotic arm and a CAD model of the object to be polished. An offline polishing reference trajectory is established through the CAD model of the serial robotic arm and the CAD model of the object to be polished. The simulation module controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory. The offline trajectory conversion module converts the data stream during simulation into a polishing reference trajectory when the simulation module controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory. The online control module calculates the deviation between the end position of the serial robotic arm and the polishing reference trajectory to generate guiding force information and transmits the guiding force information to the tactile force feedback device.
[0015] The offline-to-online programming teaching method for robotic arm trajectory disclosed in this invention includes the following steps:
[0016] First, the trajectory conversion and control device establishes a computer-aided design model of the serial robotic arm and a computer-aided design model of the object to be polished. The serial robotic arm is equipped with a torque sensor and a polishing device. Next, the trajectory conversion and control device establishes an offline polishing reference trajectory using the computer-aided design models of the serial robotic arm and the object to be polished. Then, the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory. Next, when the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory, the trajectory conversion and control device converts the data stream during simulation into a polishing reference trajectory. Next, the tactile force feedback device transmits position and direction commands. Next, the trajectory... The trajectory conversion and control device establishes connections with both the tactile feedback device and the serial robotic arm. Next, the trajectory conversion and control device receives position and direction commands from the tactile feedback device. Then, it transmits these commands to the serial robotic arm. The serial robotic arm controls its end-effector position and direction based on the position and direction commands. It then transmits the controlled end-effector position and direction back to the trajectory conversion and control device. Next, the trajectory conversion and control device calculates the deviation between the end-effector position and the polishing reference trajectory to generate a guiding force message. This guiding force message is then transmitted to the tactile feedback device. Finally, the tactile feedback device adjusts the position commands based on the guiding force message.
[0017] The system and method disclosed in this invention are as described above. The difference between them and the prior art is that the trajectory conversion and control device establishes an offline polishing reference trajectory and performs polishing operation simulation. The data stream during the simulation is converted into a polishing reference trajectory. The trajectory conversion and control device calculates the deviation between the end position of the serial robotic arm and the polishing reference trajectory to generate guiding force information. The tactile force feedback device adjusts the position command according to the guiding force information.
[0018] Through the above-mentioned technical means, the present invention can achieve the technical effect of integrating offline programming and online programming to provide robotic arm trajectory teaching.
Implementation Method
[0020] The embodiments of the present invention will be described in detail below with reference to the drawings and examples, so that the implementation process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0021] The following first describes the offline-to-online programming teaching system for robotic arm trajectories disclosed in this invention, and please refer to "Figure 1" and "Figure 2". "Figure 1" is a system block diagram of the offline-to-online programming teaching system for robotic arm trajectories of this invention; "Figure 2" is a schematic diagram of the architecture of the offline-to-online programming teaching system for robotic arm trajectories of this invention.
[0022] The offline-to-online programming teaching system for robotic arm trajectory disclosed in this invention includes: a tactile force feedback device 10, a serial robotic arm 20, and a trajectory conversion and control device 30. The trajectory conversion and control device 30 further includes: an offline trajectory programming module 31, a simulation module 32, an offline trajectory conversion module 33, and an online control module 34.
[0023] The object to be polished 41 is fixed on the polishing platform 40, so that when the serial robotic arm 20 performs polishing operation on the object to be polished 41, the object to be polished 41 will not be affected by external forces and will not be displaced. Fixing the object to be polished 41 on the polishing platform 40 also allows the computer-aided design model of the object to be polished 41 established by the offline trajectory programming module 31 of the trajectory conversion and control device 30 to be fixed in the actual position.
[0024] The serial robotic arm 20 is equipped with a torque sensor 201 and a polishing device 202. The polishing device 202 is used by the serial robotic arm 20 to perform polishing operations on the object 41 to be polished. The torque sensor 201 senses the contact force between the polishing device 202 and the object 41 to be polished during the polishing operation.
[0025] The offline trajectory programming module 31 of the trajectory conversion and control device 30 will also establish a computer-aided design model of the serial robotic arm 20. The offline trajectory programming module 31 of the trajectory conversion and control device 30 can establish an offline polishing reference trajectory by means of the computer-aided design model of the serial robotic arm 20 and the computer-aided design model of the object to be polished 41.
[0026] After the offline trajectory programming module 31 of the trajectory conversion and control device 30 establishes the offline polishing reference trajectory, the simulation module 32 of the trajectory conversion and control device 30 can simulate the polishing operation of the object 41 to be polished based on the computer-aided design model of the serial robotic arm 20, the computer-aided design model of the object 41 to be polished, and the offline polishing reference trajectory.
[0027] When the simulation module 32 of the trajectory conversion and control device 30 simulates the polishing operation of the object 41 to be polished, the offline trajectory conversion module 33 of the trajectory conversion and control device 30 will convert the data stream of the simulation process of the simulation module 32 of the trajectory conversion and control device 30 into a polishing reference trajectory. That is, the offline trajectory conversion module 33 of the trajectory conversion and control device 30 will periodically obtain the end position and end direction of the serial robotic arm 20 from the data stream of the simulation module 32 of the trajectory conversion and control device 30, and then generate a polishing reference trajectory in sequence from the obtained end position and end direction of the serial robotic arm 20.
[0028] The tactile force feedback device 10 and the serial robotic arm 20 are respectively connected to the trajectory conversion and control device 30 through wired or wireless transmission methods. The aforementioned wired transmission methods are, for example, cable networks, fiber optic networks, etc., and the aforementioned wireless transmission methods are, for example, Wi-Fi, mobile communication networks (e.g., 3G, 4G, 5G, etc.). These are merely examples and are not intended to limit the scope of application of the present invention.
[0029] Please refer to "Figure 3", which is a block diagram of the guiding force information for the offline to online programming teaching of the robot arm trajectory of the present invention.
[0030] The tactile feedback device 10 provides the user with remote control of the serial robotic arm 20. The user operates the tactile feedback device 10 to transmit position and direction commands. The trajectory conversion and control device 30 can receive position and direction commands from the tactile feedback device 10. The position and direction commands control the end position and end direction of the serial robotic arm 20. The end position and end direction of the serial robotic arm 20 are the position and direction of the polishing device 202.
[0031] The trajectory conversion and control device 30 then transmits the position command and direction command to the serial robotic arm 20. The serial robotic arm 20 can control the end position and end direction of the serial robotic arm according to the received position command and direction command. The serial robotic arm 20 then feeds back the end position and end direction of the serial robotic arm 20 to the trajectory conversion and control device 30.
[0032] The online control module 34 of the trajectory conversion and control device 30 can calculate the deviation between the end position of the serial robotic arm 20 and the polishing reference trajectory to generate guiding force information. When the trajectory conversion and control device 30 generates guiding force information, it can transmit the guiding force information to the tactile force feedback device 10.
[0033] It is worth noting that the deviation between the end position of the serial robotic arm 20 and the polishing reference trajectory is proportional to the guiding force information. That is, the greater the deviation between the end position of the serial robotic arm 20 and the polishing reference trajectory, the greater the guiding force information calculated by the trajectory conversion and control device 30. Conversely, the smaller the deviation between the end position of the serial robotic arm 20 and the polishing reference trajectory, the smaller the guiding force information calculated by the trajectory conversion and control device 30.
[0034] When the self-trajector conversion and control device 30 receives the guiding force message, the tactile force feedback device 10 enables the user to feel the guiding force message fed back by the tactile force feedback device 10. The user can operate the tactile force feedback device 10 to manipulate the end position of the serial robotic arm 20 again according to the magnitude of the guiding force message, so as to operate the tactile force feedback device 10 to adjust the position command. That is, the user can operate the tactile force feedback device 10 to make adjustments according to the guiding force message felt.
[0035] Please refer to Figure 4A, which is a schematic diagram of the scope of the offline-to-online programming teaching of the robot arm trajectory of the present invention.
[0036] In order to provide a smooth user experience in operating the tactile feedback device 10, an effective range 51 can be further set on the object to be polished 41. The effective range 51 is such that the trajectory conversion and control device 30 will only transmit the guiding force information to the tactile feedback device 10 when the position of the polishing device 202 (i.e., the end position) of the serial robotic arm 20 is within the effective range 51 set on the object to be polished 41. In this case, the position of the polishing device 202 of the serial robotic arm 20 is outside the effective range 51 set on the object to be polished 41. At this time, the trajectory conversion and control device 30 will not transmit the guiding force information to the tactile feedback device 10, that is, the user can freely operate the tactile feedback device 10 to control the serial robotic arm 20.
[0037] Please refer to Figure 4B, which is a schematic diagram of the scope of the offline-to-online programming teaching of the robot arm trajectory of the present invention.
[0038] In Figure 4B, the polishing device 202 of the serial robotic arm 20 is located within the effective range 51 set by the object to be polished 41. At this time, the trajectory conversion and control device 30 will transmit the guiding force information to the tactile force feedback device 10. The user can feel the guiding force information and make the tactile force feedback device 10 adjust. That is, the user can operate the tactile force feedback device 10 to manipulate the end position of the serial robotic arm 20 again according to the magnitude of the guiding force information.
[0039] The serial robotic arm 20 has six degrees of freedom. When the torque sensor 201 of the serial robotic arm 20 senses that the polishing device 202 comes into contact with the object to be polished 41 and generates a contact force, the serial robotic arm 20 will transmit the contact force to the trajectory conversion and control device 30.
[0040] The trajectory conversion and control device 30 can receive the contact force from the serial robotic arm 20, and then transmit the contact force to the tactile feedback device 10. The user can feel the contact force through the tactile feedback device 10. When the contact force is greater than 0 (that is, the polishing device of the serial robotic arm 20 has contacted the object to be polished), the trajectory conversion and control device 30 sends the adjustment parameters to the serial robotic arm 20. The serial robotic arm 20 further controls the movement of the serial robotic arm according to the adjustment parameters. The adjustment parameters are to provide the serial robotic arm 20 with proportional adjustment when it is operating, so that the contact force does not exceed the preset value. This is to avoid the user operating the tactile feedback device 10 incorrectly or being operated by an uncontrolled external force, causing damage to the surface of the object to be polished 41 when polishing.
[0041] Next, the operating system and method of the first embodiment of the present invention will be described below with reference to the first embodiment. Please also refer to Figures 5A and 5B, which are flowcharts of the offline to online programming teaching method for robotic arm trajectory of the present invention.
[0042] The offline-to-online programming teaching method for robotic arm trajectory disclosed in this invention includes the following steps:
[0043] First, the trajectory conversion and control device establishes a computer-aided design model of the serial robotic arm and a computer-aided design model of the object to be polished. The serial robotic arm is equipped with a torque sensor and a polishing device (step 601). Next, the trajectory conversion and control device establishes an offline polishing reference trajectory through the computer-aided design model of the serial robotic arm and the computer-aided design model of the object to be polished (step 602). Next, the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory (step 603). Next, when the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory, the trajectory conversion and control device converts the data stream during simulation into a polishing reference trajectory (step 604). Next, the tactile force feedback device transmits position and direction commands (step 605). Next, the trajectory conversion and control device respectively... A connection is established with the tactile feedback device and the serial robotic arm (step 606); then, the trajectory conversion and control device receives position and direction commands from the tactile feedback device (step 607); then, the trajectory conversion and control device transmits the position and direction commands to the serial robotic arm (step 608); then, the serial robotic arm controls the end-effector position and end-effector direction according to the position and direction commands (step 609); then, the serial robotic arm transmits the controlled end-effector position and end-effector direction to the trajectory conversion and control device (step 610); then, the trajectory conversion and control device calculates the deviation between the end-effector position and the polishing reference trajectory to generate guiding force information (step 611); then, the guiding force information is transmitted to the tactile feedback device (step 612); finally, the tactile feedback device adjusts the position command according to the guiding force information (step 613).
[0044] In summary, it can be seen that the difference between the present invention and the prior art is that the trajectory conversion and control device establishes an offline polishing reference trajectory and performs polishing operation simulation. Based on the data stream during the simulation, it is converted into a polishing reference trajectory. The trajectory conversion and control device calculates the deviation between the end position of the serial robotic arm and the polishing reference trajectory to generate guiding force information. The tactile force feedback device adjusts the position command based on the guiding force information.
[0045] This technical means can solve the problems of unexpected processing difficulties when offline programming of robotic arm trajectories is applied to actual production, and the problem of online programming taking too much time to establish robotic arm trajectories, which exist in the prior art. In this way, the technical effect of integrating offline programming and online programming to provide robotic arm trajectory teaching can be achieved.
[0046] Although the embodiments disclosed in this invention are as described above, the content described is not intended to directly limit the scope of patent protection of this invention. Anyone skilled in the art to which this invention pertains may make some modifications in form and detail of the implementation without departing from the spirit and scope disclosed in this invention. The scope of patent protection of this invention shall still be determined by the appended claims. [Simplified Explanation of the Diagram]
[0019] Figure 1 is a system block diagram of the offline-to-online programming teaching system for the robotic arm trajectory of the present invention. Figure 2 is a schematic diagram of the architecture of the offline-to-online programming teaching system for the robotic arm trajectory of the present invention. Figure 3 is a block diagram of the guiding force information for the offline-to-online programming teaching system for the robotic arm trajectory of the present invention. Figures 4A and 4B are schematic diagrams of the scope of action of the offline-to-online programming teaching system for the robotic arm trajectory of the present invention. Figures 5A and 5B are flowcharts of the offline-to-online programming teaching method for the robotic arm trajectory of the present invention.
Claims
1. An offline-to-online programming teaching system for robotic arm trajectories, comprising: a tactile force feedback device for transmitting a position command and a direction command, and receiving a guiding force message to adjust the position command according to the guiding force message; a serial robotic arm equipped with a torque sensor and a polishing device, controlling the end-effector position and end-effector direction of the serial robotic arm according to the received position command and direction command, and transmitting the controlled end-effector position and end-effector direction of the serial robotic arm; and a trajectory conversion and control device for establishing connections with the tactile force feedback device and the serial robotic arm, receiving the position command and direction command from the tactile force feedback device, transmitting the position command and direction command to the serial robotic arm, receiving the end-effector position and end-effector direction from the serial robotic arm, and transmitting the guiding force message to the tactile force feedback device, the trajectory conversion and control device further comprising: an offline trajectory programming module for establishing computer-aided design (CAD) of the serial robotic arm. The system includes a computer-aided design (CAD) model of the robotic arm and a computer-aided design model of the object to be polished, which are used to establish an offline polishing reference trajectory; a simulation module that controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory; an offline trajectory conversion module that converts the data stream during simulation into a polishing reference trajectory when the simulation module controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory; and an online control module that calculates the deviation between the end position of the robotic arm and the polishing reference trajectory to generate the guiding force information and transmits the guiding force information to the tactile force feedback device.
2. The offline-to-online programming teaching system for robotic arm trajectories as described in claim 1, wherein the offline trajectory conversion module converts the polishing reference trajectory based on the data stream of the simulation module by periodically obtaining the end positions of the serial robotic arms from the data stream of the simulation module, and then sequentially generating the polishing reference trajectory from the end positions of multiple serial robotic arms.
3. The offline-to-online programming teaching system for robotic arm trajectories as described in claim 1, wherein the deviation of the end position of the serial robotic arm from the polishing reference trajectory is proportional to the guiding force information.
4. The offline-to-online programming teaching system for robotic arm trajectory as described in claim 1, wherein the trajectory conversion and control device further sets an effective range on the object to be polished, and when the deviation between the end position of the serial robotic arm and the polishing reference trajectory is greater than the effective range, the trajectory conversion and control device will not transmit the guiding force information to the tactile force feedback device.
5. The offline-to-online programming teaching system for robotic arm trajectory as described in claim 1, wherein the torque / torque sensor senses a contact force when the polishing device performs a polishing operation with the object to be polished, the trajectory conversion and control device receives the contact force from the serial robotic arm, the trajectory conversion and control device transmits the contact force to the tactile force feedback device, and when the contact force is greater than 0, the trajectory conversion and control device sends an adjustment parameter to the serial robotic arm, the adjustment parameter providing proportional adjustment during the operation of the serial robotic arm so that the contact force does not exceed a preset value.
6. An offline-to-online programming teaching method for robotic arm trajectory, comprising the following steps: A trajectory conversion and control device establishes a computer-aided design model of a serial robotic arm and a computer-aided design model of an object to be polished, wherein the serial robotic arm is equipped with a torque sensor and a polishing device. The trajectory conversion and control device establishes an offline polishing reference trajectory through the computer-aided design model of the serial robotic arm and the computer-aided design model of the object to be polished; the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory; when the trajectory conversion and control device controls the robotic arm to simulate polishing operations on the object to be polished based on the offline polishing reference trajectory, the trajectory conversion and control device converts the data stream during simulation into a polishing reference trajectory; a tactile force feedback device transmits a position command and a direction command; the trajectory conversion and control device establishes connections with the tactile force feedback device and the serial robotic arm respectively; the trajectory conversion and control device receives the position command and the direction command from the tactile force feedback device; the trajectory conversion and control device transmits the position command and the direction command to the serial robotic arm; The serial robotic arm controls the end-effector position and end-effector direction according to the position command and the direction command; the serial robotic arm transmits the controlled end-effector position and end-effector direction to the trajectory conversion and control device; the trajectory conversion and control device calculates the deviation between the end-effector position and the polishing reference trajectory to generate a guiding force message; the guiding force message is transmitted to the tactile force feedback device; and the tactile force feedback device adjusts the position command according to the guiding force message.
7. The offline-to-online programming teaching method for robotic arm trajectory as described in claim 6, wherein the step of the trajectory conversion and control device converting the polishing reference trajectory according to the simulation data stream is to periodically obtain the end positions of the serial robotic arms from the simulation data stream, and then sequentially generate the polishing reference trajectory from the end positions of multiple robotic arms.
8. The offline-to-online programming teaching method for robotic arm trajectory as described in claim 6, wherein the deviation of the end position of the serial robotic arm from the polishing reference trajectory is proportional to the guiding force information.
9. The offline-to-online programming teaching method for robotic arm trajectory as described in claim 6, wherein the offline-to-online programming teaching method for robotic arm trajectory further comprises the following steps: the trajectory conversion and control device further sets an effective range on the object to be polished; and when the deviation between the end position of the serial robotic arm and the polishing reference trajectory is greater than the effective range, the trajectory conversion and control device will not transmit the guiding force information to the tactile force feedback device.
10. The offline-to-online programming teaching method for robotic arm trajectories as described in claim 6, wherein the offline-to-online programming teaching method for robotic arm trajectories further comprises the following steps:
11. The torque sensor senses a contact force when the polishing device performs a polishing operation with the object to be polished; the trajectory conversion and control device receives the contact force from the serial robotic arm; The trajectory conversion and control device transmits the contact force to the tactile force feedback device; when the contact force is greater than 0, the trajectory conversion and control device sends an adjustment parameter to the serial robotic arm; The series-connected robotic arm adjusts its operating ratio according to the adjustment parameters to ensure that the contact force does not exceed a preset value.