Optimally Controlled Tape Removal System and Method

Abstract

An automated system and method are provided for removing tape from an object surface using an end effector attached to a robotic arm. The end effector includes a gripping mechanism and a force sensor, and the end effector is commanded by a controller to automatically detect a peeling state and adjust its peeling parameters to optimize removal while the end effector moves along the object surface to remove the tape.

Description

Background Art

[0001] Various tapes such as masking tape or protective tape can be applied to the surface of an object such as the surface of automotive parts or replacement parts. These tapes can be removed from the surface of the object by manual labor or a robotic system. Current tape peeling processes and systems are generally labor-intensive and not performed in an optimally controlled manner.

Summary of the Invention

[0002] It is desirable to remove the tape from the surface of the object in an optimally controlled manner. When peeling the tape, there are various possible trajectories including various peeling parameters (including peeling angle, peeling speed, etc.). Depending on the surface of the object and the conditions applied to the tape, a specific peeling force may be preferred in order to avoid peeling defects such as tearing of the tape, damage to the surface of the object, and peeling of the paint (for example, when the surface of the object is a painted surface). The present disclosure provides an automated system and method for removing tape from the surface of an object. The automated system includes a gripper for removing the tape from the surface of the object and an accompanying algorithm for ensuring that a desired peeling parameter is maintained by following an appropriate trajectory. The optimal parameters may be determined by a data-driven approach and may vary depending on the tape type, substrate, and environmental and situation conditions.

[0003] In one aspect, the present disclosure describes a method for removing a tape attached to an object surface, the method including the steps of providing a robot including an end effector having a gripping mechanism and a force sensor; initializing the robot to position the end effector relative to the tape on the object surface; gripping the tab of the tape with the gripping mechanism; moving the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters. The method further includes measuring a peeling force by the force sensor while the end effector moves along the object surface to remove the tape; adjusting the movement trajectory of the end effector to maintain the value of the peeling force within a desired range; and determining at least another peeling parameter of the set of peeling parameters based on the peeling force, the determining including determining at least one of a peeling speed and a peeling angle.

[0004] In another aspect, the present disclosure describes an automated system for removing a tape from an object surface, the system including an end effector having a gripping mechanism and a force sensor; a vision system having one or more imaging sensors for acquiring imaging data about the tape, the object surface, and the end effector; and a controller operatively connected to the end effector and the vision system. The controller is configured to initialize the end effector relative to the tape on the object surface, grip the tab of the tape with the gripping mechanism, move the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters. The controller is further configured to measure a peeling force by the force sensor while the end effector moves along the object surface to remove the tape, adjust the movement trajectory of the end effector to maintain the value of the peeling force within a desired range, and determine at least another peeling parameter of the set of peeling parameters based on the peeling force, the determining including determining at least one of a peeling speed and a peeling angle.

[0005] Various unexpected results and advantages are obtained in the exemplary embodiments of the present disclosure. One such advantage of the exemplary embodiments of the present disclosure is that the methods and systems described herein can ensure that no tape breakage occurs during removal by moving the end effector at an optimized peel angle and speed and maintaining a record of the peel force.

[0006] The above is an overview of the various aspects and advantages of the exemplary embodiments of the present disclosure. The above "Summary of the Invention" is not intended to describe each illustrated or all realized embodiments of the exemplary embodiments of the present disclosure. The following drawings and "Detailed Description of the Invention" illustrate specific preferred embodiments using the principles disclosed herein in more detail.

Brief Description of the Drawings

[0007] The present disclosure can be more fully understood by considering the following detailed description of various embodiments of the present disclosure in conjunction with the accompanying drawings.

Figure 1

Figure 2A

Figure 2B

Figure 2C

Figure 3A

Figure 3B

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[0008] In the drawings, like reference numerals indicate like elements. The drawings identified above may not be drawn to scale and are provided to illustrate various embodiments of the present disclosure, but as noted in the "DETAILED DESCRIPTION," other embodiments are also contemplated. In all cases, the present disclosure is described by presenting the disclosure herein in terms of exemplary embodiments rather than by way of explicit limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that fall within the scope and spirit of the present disclosure.

DETAILED DESCRIPTION

[0009] The present disclosure provides an automated system and method for removing tape from an object surface. The automated system includes a gripper for removing tape from an object surface and an accompanying algorithm for ensuring that a desired peel parameter is maintained while following an appropriate trajectory. The optimal parameters may be determined by a data-driven approach and may vary depending on the tape type, substrate, and environmental and situational conditions.

[0010] FIG. 1 shows a side perspective view of a tape removal system 100 including an end effector 20 for removing a tape 5 from an object surface 2 according to an embodiment. The tape removal system 100 further includes a robotic arm 10. The robotic arm 10 includes a plurality of arm portions 12a, 12b connected by joints 13a, 13b. The end effector 20 is functionally connected to a mounting interface 14 at the distal end of the robotic arm 10. The mounting interface 14 may be designed based on specific mounting criteria and may be compatible with various end effector tools based on the same mounting criteria. In some embodiments, the mounting interface 14 may include various mechanical and electrical means for functionally connecting the end effector 20 to the robotic arm 10. For example, the mounting interface may include any suitable fastening device for mechanically attaching the smart end effector 20 to the robotic arm 10. The mounting interface may further include any suitable electrical connection for communicating electrical signals between the end effector and the robotic arm or for supplying power from the robotic arm to the end effector.

[0011] The robotic controller 16 is used to execute a robotic arm command program to control the movement of the robotic arm 10 so that the movement trajectory 51 of the end effector 20 can be precisely controlled. In some embodiments, the robotic arm command program may control the movement of the robotic arm by a set of motion parameters including, for example, the position, orientation, and speed of the arm portions and joints.

[0012] In the embodiment shown in FIG. 1, the adhesive tape 5 is attached to an object surface 2 which can be, for example, the surface of an automotive part (e.g., the rear window surface shown in FIG. 1). The object surface may have a flat surface or a non-planar manifold with various surface curvatures. The robot controller 16 can control the movement of the robot arm such that the end effector 20 moves closer to the object surface and traverses the object surface 2, and grips and removes the tape 5 attached to the object surface 2. In some embodiments, the robot controller 16 may include any power interface to a power source of the robot controller 16 for supplying power to the end effector 20 in the form of electricity, pneumatic pressure, or the like.

[0013] The end effector 20 includes a gripping mechanism such as, for example, a gripper jaw to grip the edge of the tape 5. The tape 5 may be any flexible adhesive tape. The tape 5 may include an adhesive surface that is adhesively bonded to the object surface 2. The adhesive surface of the tape 5 may include any suitable adhesive such as, for example, a removable adhesive including rubber, silicone, acrylic adhesive, etc. The adhesive surface may include a non-stretchable release adhesive such as, for example, a pressure-sensitive adhesive (PSA) or an epoxy adhesive. The adhesive surface can be disposed on a flexible backing layer having sufficient flexibility to allow the adhesive surface to be separated from the object surface. The adhesive tape 5 may also provide shape conformity and elastic properties required by the desired application. The gripping mechanism of the end effector 20 can grip the end of a tape piece or a tape tab, for example, by a pair of gripper jaws. In some embodiments, the end of the tape can be made non-adhesive, that is, a tape tab can be provided at the edge of the tape 5. The tape tab can be formed as an extension of the flexible backing layer that is further away from the adhesive surface. In various embodiments, the gripping mechanism may further include a wedge, a scraper, a blower, or a combination thereof to facilitate the gripping of the tape tab by the gripping mechanism. For example, the tape tab can be lifted by a blower for gripping.

[0014] In some embodiments, the end effector 20 can include a winding mechanism for winding up the slack of the tape as the tape removal progresses. The winding mechanism can wind up the tape at a speed such that a distance from the end effector to the object surface remains unchanged.

[0015] In operation, the tape removal system 100 starts by initializing communication between the robotic arm and its end effector. The robotic arm (e.g., robotic arm 10) and the end effector (e.g., end effector 20) communicate with each other to update their respective status information. Such respective status information can include, for example, power on self-tests (POST), starting orientation and coordinate system, tape peeling parameters (e.g., peeling force, peeling speed, peeling angle, etc.). The end effector may receive the status information of the robotic arm from the robotic control interface of the robotic arm. Examples of the status information of the robotic arm can include a set of motion parameters including the position, orientation, or speed of the arm portion and joints.

[0016] The operating state of the end effector when removing the tape can be detected by various sensors. For example, the embodiment shown in FIG. 1 includes a vision system 32 for providing machine vision or 3D vision sensing. The vision system 32 can capture the image data of the end effector, analyze this image data to determine the operating state of the end effector, and send a notification or command to the robot controller to stop or adjust the movement of the robotic arm, thereby determining whether to interrupt the initialization of the robotic arm. For example, in some embodiments, when an emergency event is detected, a notification for stopping the initialization can be sent.

[0017] The vision system 32 can also provide machine vision or 3D vision sensing to determine the state of the tape 5 on the object surface 2. When the vision system 32 detects the tape to be removed on the object surface, a command is sent to the robot controller, and the movement of the robot arm can be adjusted to place the end effector at an initial position for preparation for removal.

[0018] The vision system 32 can further determine the removal path of the tape 5 on the object surface 2. The vision system 32 can acquire imaging data about the tape 5 on the object surface 2 and provide surface mapping information. For example, a 2D perspective projection or contour of the tape 5 on the object surface 2 can be generated and processed to determine the removal path of the tape 5 on the object surface 2. In some embodiments, the removal path of the tape 5 on the object surface 2 can be predetermined by scanning the surface, and the corresponding coordinates (x, y, z) of the tape with respect to the peeling coordinate system of the end effector can be stored. The determined tape removal path can be communicated to the robot controller as an input for adjusting the movement parameters of the robot arm and the peeling parameters of the end effector.

[0019] The end effector 20 can be attached to the attachment interface of the robot arm 10. When moving around the object surface 2, the end effector 20 is controlled to adjust its position, orientation, movement trajectory, etc. according to the movement of the robot arm 10. When the end effector grips the tab of the tape 5 by the gripping mechanism, a command including an initial set of peeling parameters is sent to the end effector, and the end effector can be moved along the object surface to remove the tape from the object surface. The set of peeling parameters includes, for example, peeling force, peeling speed, and peeling angle. The peeling angle represents the orientation of the end effector with respect to the surface normal. Examples of the peeling angle can include a peeling pitch angle, a peeling yaw angle, and a peeling roll angle with respect to the surface normal of the object surface, and these can be determined by the vision system.

[0020] Figures 2A to 2C show schematic views of various peeling angles in a peeling coordinate system for an end effector gripping a tape according to some embodiments. The end effector moves along the peeling direction 21 at a certain peeling speed. The orientation of the end effector can be adjusted by changing at least one of the pitch angle θ, the yaw angle ψ, and the roll angle φ. The peeling speed can be in the range of, for example, about 0.001 m / second to about 1.0 m / second. The pitch angle θ can be in the range of, for example, about 0 to about 180 degrees. The yaw angle ψ can be in the range of, for example, about 0 to about 90 degrees. The roll angle φ can be in the range of, for example, about 0 to about 5 degrees. In some embodiments, the roll angle φ may be an angle of about 0 degrees that is substantially fixed.

[0021] Figure 3A shows a block diagram of a tape removal system 300 according to an embodiment. The tape removal system 300 includes an end effector 310 functionally connected to a powered robotic arm 320. The end effector 310 includes one or more sensors 312 (e.g., sensor 1,... sensor N) for detecting the operating state information of the end effector 310 and the removal state of the tape when gripping and moving the tape. The plurality of sensors 312 can include, for example, a force sensor for measuring the real-time force applied to stretch and remove the tape 5. Suitable force sensors can include, for example, a multi-axis load cell that uses silicon strain gauges to measure all six components of force and torque in a three-dimensional (3D) coordinate system. The force sensor may include a transducer, interface electronics, and a cable.

[0022] Sensor 312 may also include one or more imaging sensors or vision sensors that may be included by or supplement the vision system 32 of FIG. 1. In some embodiments, one or more of the vision sensors can be integrated with the vision system 32. In some embodiments, one or more of the vision sensors can be integrated with the end effector 20 and functionally connected to the vision system 32. The vision system 32 may receive various imaging data from the imaging sensors and process the data to obtain relevant information such as, for example, the state information of the tape and the object surface. For example, a vision sensor or imaging sensor disposed on the end effector 20 can detect the remaining portion of the tape on the object surface and communicate the imaging data to the vision system 32. The vision system 32 can determine the removal state of the tape based on the image data. The image sensor can detect the relative position / orientation of the end effector with respect to the object surface, and the vision system 32 can measure the real-time change in the displacement between the object surface and the end effector based on the image data.

[0023] Sensor 312 may also include various sensors for detecting environmental information such as, for example, ambient temperature, ambient humidity, or other conditions of the end effector, tape, and / or object surface. In the operating environment, one or more wireless-enabled sensing stations may be provided, including one or more sensors and a controller configured to output data indicating the sensed environmental conditions. The detected environmental condition data can be used to adjust peeling parameters such as, for example, an acceptable peeling speed. Under various temperatures and humidities, the material properties of the tape adhesive and backing may change, thereby changing the removal force for a given peeling parameter. By incorporating environmental information, it is possible to obtain a more accurate estimate of the desired peeling parameters, ensure that the tape is removed cleanly, without damage to the backing, and without damage to the underlying substrate / object surface.

[0024] The sensing signal (e.g., analog sensor signal) from the sensor 312 is received and processed by the processor unit 314. The processor unit 314 may include an analog-to-digital converter (ADC) component that samples the analog sensor signal and converts the analog sensor signal into a digital signal. The processor unit 314 may further include a digital signal processing component that processes and extracts the digital signal to generate real-time tool status information, notifications, or commands, and communicates the generated information to the robot controller. In some embodiments, the processor unit 314 may be integrated with the robot controller 16 and may not be located on the end effector.

[0025] In some embodiments, the real-time tool status information generated by the processor unit 314 may include, for example, the current position / orientation information of the end effector with respect to the tape 5 on the object surface 2. The real-time tool status information may further include the measured peeling force. The real-time tool status information may further include, for example, the removal status of the tape, the real-time change in the displacement between the object surface and the end effector, etc.

[0026] In some embodiments, the processor unit 314 can combine the pre-determined tape removal path data and the initial set of peeling parameters of the end effector to derive an initial movement trajectory for the end effector tool to move on the object surface 2 and remove the tape from the object surface 2.

[0027] In some embodiments, the real-time notifications generated by the processor unit 314 may include, for example, position notifications (e.g., a notification to the robot controller that the end effector is at the edge of the tape), removal notifications (e.g., a notification to the robot controller that the tape has been partially or completely removed), etc.

[0028] In some embodiments, the instructions generated by the processor unit 314 may include, for example, tool operation instructions related to a method of controlling the operation of the end effector, and movement instructions for instructing the robot controller to adjust the position of the end effector, the movement trajectory of the end effector, the peeling speed, the orientation of the end effector, etc. The tool operation instructions may include, for example, on / off instructions to the robot controller for turning the end effector on / off, motor control instructions to the robot controller for controlling the operation of the motor of the end effector, etc.

[0029] Real-time status information, notifications, or instructions from the end effector tool 310 can be sent to the robot controller 16 via the tool control interface 316 and the robot control interface 326. Then, the robot controller 16 can simultaneously update the motion parameters of the robot arm so that it can precisely control the movement trajectory of the end effector 310 using the real-time status information. The robot controller 16 can also control the tape removal system 100 accordingly by operating immediately after receiving a notification from the end effector tool 310 or by following an instruction. In some embodiments, the robot controller 16 may receive real-time status information, notifications, or instructions from the end effector, interpret the received information, check whether the notification or instruction is compliant with a preset rule, and implement the instruction accordingly. For example, the robot controller 16 may provide a movement vector to the end effector for adjusting its position relative to the tape on the object surface. The robot controller 16 can instruct the robot arm to apply an appropriate force to peel the tape from the object surface. The robot controller 16 can provide an emergency stop command to the end effector to stop it when an emergency condition is determined by the robot controller. Also, the robot controller 16 can instruct each part to perform other operations.

[0030] Figure 3B is a block diagram of the robot controller 16 according to one embodiment. The robot controller 16 is functionally connected to various parts of the system and regulates the operation of the system by various control devices, processors, memory devices, etc. In the illustrated embodiment of FIG. 3B, the robot controller 16 includes an input unit 162 for receiving various sensing data from the vision system 32, the sensor 312, and / or the end effector 310. For example, the input unit 162 may receive imaging data regarding the remaining portion of the tape on the object surface from the imaging sensor. The robot controller 16 further includes a command unit 164 that processes the data received by the input unit 162 and provides commands to various parts of the system based on the received data. For example, the command unit 164 can process the received imaging data to determine the removal state of the tape on the object surface. In some embodiments, the vision system 32 may acquire and process the imaging data and transmit the processed imaging data to the input unit 162. The robot controller 16 further includes a storage unit 166 that stores information including, for example, a predetermined relationship between peeling parameters for various combinations of the tape and the substrate, a predetermined tape removal path on the substrate / object surface, preset rules or guidelines, dynamically updated state information, etc. The preset rules or guidelines can be determined in advance for various events that may occur during the removal of the tape. For example, the user operating the system can set a rule that the detection of tape breakage is an emergency event.

[0031] Figure 4 shows a flowchart of a method 400 for removing tape from an object surface according to one embodiment. Method 400 can be implemented by various tape removal systems described herein, including the tape removal system 300 of FIGS. 3A and 3B. At 410, equip the robot with an end effector. The robot can include a robotic arm such as the robotic arm 10 of FIG. 1. An end effector such as the end effector 20 of FIG. 1 is functionally connected to the distal end of the robotic arm 10. The end effector includes a gripping mechanism configured to grip the edge of the tape on the object surface. The end effector further includes a force sensor for measuring the real-time stretching force applied to the tape when removing the tape from the object surface. Next, method 400 proceeds to 420.

[0032] At 420, the tape removal system starts by initializing the robot to position the end effector and prepare to remove the tape from the object surface. The robot controller 16 can communicate with various parts of the system, such as the robotic arm, end effector, vision system, and various sensors, to update their respective position / location information, status information, and other relevant information.

[0033] The removal path of the tape on the object surface can be determined and updated using the robot controller 16. The removal path can be the 2D perspective projection or contour of the tape on the object surface. Such a 2D perspective projection or contour of the tape can be determined in advance or obtained in real time by the vision system 32. For example, the vision system may include a camera that scans the object surface to identify the position of the tape on the object surface and generates a 2D perspective projection or contour of the tape with respect to the peeling coordinate system of the end effector. In some embodiments, the geometric shape of the object surface to which the tape is attached can be represented by a digital two-dimensional (2D) or digital three-dimensional (3D) model. The digital model can be in the form of an electronic file for computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), or other suitable applications. The digital model is predetermined and can be stored, for example, in the storage unit 166 of FIG. 3B and retrieved by the robot controller 16. Using such position and profile information of the tape on the object surface, the robot controller 16 can instruct the robot arm to move the end effector to approach the tape attached to the object surface.

[0034] In some embodiments, the step of initializing the robot may include providing an initial set of peeling parameters including the peeling force, peeling speed, and peeling angle with respect to the surface normal of the object surface (e.g., peeling pitch angle, peeling yaw angle) to the end effector. In some embodiments, the step of initializing the robot may further include providing an initial movement trajectory that coincides with the removal path of the tape. The movement trajectory provides a path in the peeling coordinate system for moving the end effector. The initial movement trajectory of the end effector can be determined based on the initial peeling parameters (e.g., initial peeling speed, initial peeling angle, etc.) and the removal path of the tape on the object surface.

[0035] Next, method 400 proceeds to 430, where the robot controller commands the end effector to grip the tab of the tape on the object surface by the gripping mechanism. The gripping mechanism of the end effector can grip the tape tab by, for example, a pair of gripper jaws. In various embodiments, a wedge, a scraper, an air blower, or a combination thereof can be provided to facilitate the gripping of the tape tab by the gripping mechanism. Vision system 32 can monitor the gripping process and provide the relevant orientation / position / state information of the gripping mechanism of the tape tab to robot controller 16, enabling robot controller 16 to change the motion parameters of the robot arm and / or adjust the orientation / position of the gripping mechanism with respect to the tape tab. When the end effector grips the tape tab, method 400 then proceeds to 440.

[0036] At 440, when the end effector grips the tape tab, robot controller 16 commands the robot arm to move the end effector along the object surface according to an initial set of peeling parameters to remove the tape from the object surface. The initial set of peeling parameters includes, for example, an initial peeling force, an initial peeling speed, an initial peeling angle, etc. The initial set of peeling parameters can be determined in advance based on test data regarding the specific combination of the tape material and the object surface material. Next, method 400 proceeds to 450.

[0037] FIG. 5 is a 3D plot of peel force (N / m) versus peel pitch angle (degrees) and peel speed (m / sec) for a specific combination of tape material and object surface material, with the tape attached to the object surface in a planar configuration. By using pre-measured test data for a selected tape / substrate combination, an optimal peel pitch angle can be determined, the speed parameter can be selected automatically or by the user (to meet cycle time requirements), and the peel speed can be held at a minimum peel force value. Additional constraints, such as peel yaw angle, substrate conditions, ambient / environmental conditions, roll down, etc., can also be considered in the test data to provide a clear description of the tape / substrate combination with respect to peel parameters. The test data can be stored, for example, in the storage unit 166 of FIG. 3B. The robot controller can determine an appropriate set of peel parameters based on the test data to prevent peel defects such as slivering, cracking, other tape breakage, or damage to the substrate / object surface. When the tape is used as a mask on the object surface for surface coating, the optimized peel parameters based on the test data can help maintain a clean removal and a sharp coating line.

[0038] At 450, the robot controller 16 commands the force sensor to measure the peel force acting on the tape and remove the tape from the object surface. The force measurement value can be obtained, for example, from a multi-axis force sensor. The measured data can include force and torque measurement data along the x-axis, y-axis, and z-axis of the force sensor. The force measurement value is transformed from the force sensor frame to the robot peel coordinate frame. The peel force measurement value is then calculated by taking the Euclidean (L2) norm of the rotated x, y, and z force measurement values obtained from the sensor. The measurement value can be filtered by a low-pass filter to reduce noise and then the value is compared to the expected average peel force value for a given peel parameter. The method 400 then proceeds to 460.

[0039] At 460, the robot controller 16 commands the robot arm to adjust the movement trajectory of the end effector to maintain the value of the peeling force within a desired range. The end effector is provided with an initial movement trajectory that coincides with the tape removal path when the system is initialized. During tape removal, the movement trajectory needs to be adjusted for various reasons. In some cases, when the tape is gripped and removed by the end effector, the portion of the tape being removed may be stretched and elongated. In other cases, the surface of the object to which the tape is attached may move during removal. The movement trajectory needs to be adjusted to individually or collectively accommodate such deformations or displacements of the tape and / or the object surface, such that the value of the peeling force remains within the desired range. Then, method 400 proceeds to 470.

[0040] For some given peel parameters (e.g., peel angle, peel speed, etc.), there exists a given threshold value of the average peel force that can be tolerated to continue on a planned robot trajectory. The threshold value can be, for example, 2 sigma standard deviations above or below the average peel force for a given peel parameter. If the average peel force value exceeds this threshold, the planned robot trajectory needs to be changed or adjusted to maintain the desired peel force. In some embodiments, the adjustment of the robot trajectory can be done by first increasing or decreasing the peel pitch angle. When the force value is outside the threshold range, the pitch angle can be increased or decreased to raise or lower the peel force back within the acceptable range. The decision of whether to increase or decrease can be made by using predetermined data regarding a specific pair of the tape material and the object surface material, as seen in FIG. 5. By fixing other peel parameters, a calculated slice of the surface can be taken, and at the current peel angle, the sign of the slope of the slice can be determined. A negative slope may indicate that the parameter needs to be shifted lower or higher, respectively, depending on whether the excessive force is lower or higher. For a positive slope, the opposite is true, which may indicate that the parameter needs to be shifted higher or lower, respectively, depending on whether the excessive force is lower or higher. If the pitch angle cannot be increased or decreased as needed (e.g., when the pitch angle is at the upper or lower limit, or at the minimum / maximum, etc.), the peel yaw angle can be increased or decreased according to the same logic. The change in angle may correspond to the application of a position offset to the existing robot trajectory to maintain the new peel pitch angle or peel yaw angle. The position offset can be calculated by using the peel coordinate systems of FIGS. 2B and 2C that can determine a new peel direction based on the new peel angle, and based on the current pose of the robot, the offset is applied to achieve the new peel direction. In some cases, when neither the peel pitch nor the peel yaw can be changed according to the change logic, then the peel speed can be changed by the change logic and increased or decreased.The change in speed may not require changing the robot path, but may change the time step size between robot path points. For each of the described path change methods, the value of the change in pitch angle, yaw angle, or speed magnitude can be determined by obtaining the amount of peeling force (i.e., the amount of force exceeding the threshold) and multiplying by some constant. The constant can be equal to about 0 to about 5 percent of the current parameter value. Then, based on the change logic for determining whether to increase or decrease the parameter value, the constant × amount of peeling force can be added to or subtracted from the parameter value.

[0041] At 470, the robot controller 16 commands the end effector to adjust at least another peeling parameter of the set of peeling parameters based on the peeling force. In some embodiments, the peeling speed and / or the peeling angle can be adjusted based on the maintained peeling force according to a predetermined relationship between at least some of the peeling parameters. For example, FIG. 5 shows the relationship between the peeling force (N / m), the peeling pitch angle (degrees), and the peeling speed (m / sec). For a given peeling force, appropriate values of the peeling pitch angle (degrees) and the peeling speed (m / sec) can be selected according to that relationship. Similarly, for a given peeling force, an appropriate value of the peeling yaw angle or roll angle (degrees) can be selected according to that relationship. Then, method 400 proceeds to 480.

[0042] At 480, the robot controller 16 commands various sensors (e.g., vision system 32, sensor 312, etc.) to monitor and determine the state of the tape on the object surface. The robot controller 16 can give various commands to each part according to the monitored state. For example, in some cases, the robot controller 16 can receive sensor data from the sensors, process the data, and confirm that the tape has been removed from the object surface. The sensors can detect the remaining portion of the tape on the object surface, and the robot controller 16 can confirm that the removal is complete when there is no remaining portion on the object surface. In another case, the robot controller 16 can detect whether an event that brings about an adjustment of the system has occurred. For example, the robot controller 16 can process the sensor data and detect the movement of the object surface during tape removal that is a bad path for the end effector. The robot controller 16 can command the robot arm to adjust the position of the end effector to correspond to such displacement. If the automatic adjustment fails, the robot controller 16 can send a notification regarding that state. In various embodiments, the robot controller 16 can receive sensing data from various environmental sensors and determine various environmental conditions including, for example, ambient temperature and ambient humidity.

[0043] Unless otherwise indicated, all numbers representing amounts or raw materials, measured values of characteristics, etc. used in this specification and the embodiments are to be understood as being modified in all cases by the term "about". Accordingly, unless an opposite indication is given, the numerical parameters described in the foregoing specification and the list of attached embodiments can vary according to the desired characteristics that those skilled in the art seek to obtain using the teachings of the present disclosure. At a minimum, each numerical parameter should be construed at least in light of the number of significant digits reported and by applying ordinary rounding techniques, but this is not intended to limit the application of the doctrine of equivalents to the scope of the claimed embodiments.

[0044] Exemplary embodiments of the present disclosure can be subject to various modifications and changes without departing from the spirit and scope of the present disclosure. Therefore, it should be understood that the embodiments of the present disclosure are not limited to the exemplary embodiments described below, but are regulated by the limitations described in the claims and their equivalents.

[0045] List of Exemplary Embodiments The exemplary embodiments are listed below. It should be understood that any one of Embodiments 1 to 12 and any one of Embodiments 13 to 15 can be combined.

[0046] Embodiment 1 is a method for removing a tape attached to an object surface, comprising: preparing a robot including an end effector, the end effector comprising a gripping mechanism and a force sensor; initializing the robot to position the end effector with respect to the tape on the object surface; gripping an end of the tape by the gripping mechanism; moving the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters; while the end effector moves along the object surface to remove the tape, measuring a peeling force by the force sensor; adjusting the movement trajectory of the end effector to maintain the value of the peeling force within a desired range; determining at least another peeling parameter among the set of peeling parameters based on the peeling force, the step of determining at least another peeling parameter including determining at least one of a peeling speed and a peeling angle.

[0047] Embodiment 2 is the method according to Embodiment 1, wherein the step of determining at least another peeling parameter includes a step of pre-determining a relationship between at least some of the peeling parameters for the tape on the object surface.

[0048] Embodiment 3 is the method according to Embodiment 2, wherein the predetermined relationship is the relationship among the peeling force, the peeling speed, and the peeling angle.

[0049] Embodiment 4 is the method according to any one of Embodiments 1 to 3, wherein the step of initializing the robot includes the step of determining the removal path of the tape on the object surface.

[0050] Embodiment 5 is the method according to Embodiment 4, wherein the step of determining the removal path of the tape on the object surface includes a digital two-dimensional (2D) model or a digital three-dimensional (3D) model of the tape on the object surface.

[0051] Embodiment 6 is the method according to Embodiment 4 or 5, wherein the step of initializing the robot further includes the step of providing an initial movement trajectory that coincides with the removal path of the tape.

[0052] Embodiment 7 is the method according to any one of Embodiments 1 to 6, wherein the step of initializing the robot includes the step of identifying the position of the tab of the tape on the object surface.

[0053] Embodiment 8 is the method according to any one of Embodiments 1 to 7, further including the step of determining the state of the tape on the object surface.

[0054] Embodiment 9 is the method according to Embodiment 8, wherein the step of determining the state includes the step of confirming the removal of the tape from the object surface.

[0055] Embodiment 10 is the method according to Embodiment 8 or 9, wherein the step of determining the state includes the step of detecting the remaining portion of the tape on the object surface.

[0056] Embodiment 11 is the method according to any one of Embodiments 8 to 10, wherein the step of determining the state includes the step of detecting the movement of the object surface during the removal of the tape.

[0057] Embodiment 12 is the method according to any one of Embodiments 8 to 11, wherein the step of determining the state includes a step of determining environmental conditions including the ambient temperature and the ambient humidity.

[0058] Embodiment 13 is an automated system for removing a tape from an object surface, an end effector including a gripping mechanism and a force sensor, a vision system including one or more imaging sensors for acquiring imaging data about the tape, the object surface, and the end effector, and a controller functionally connected to the end effector and the vision system, wherein the controller initializes the end effector with respect to the tape on the object surface, grasps an end of the tape by the gripping mechanism, moves the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters, while the end effector moves along the object surface to remove the tape, measures a peeling force by the force sensor, adjusts a movement trajectory of the end effector to maintain the value of the peeling force within a desired range, and is configured to determine at least another peeling parameter of the set of peeling parameters based on the peeling force, the determination including determining at least one of a peeling speed and a peeling angle, and is an automated system.

[0059] Embodiment 14 further includes a robotic arm, and the end effector is attached to the robotic arm, and is the automated system of Embodiment 13.

[0060] Embodiment 15 is the automated system of Embodiment 13 or 14, wherein the controller is further configured to determine a state of the tape on the object surface based on imaging data from the vision system.

[0061] The operation of the present disclosure will be further described with respect to the following detailed examples. These examples are provided to further illustrate various specific preferred embodiments and techniques. However, it should be understood that many changes and modifications can be made while remaining within the scope of the present disclosure.

Example

[0062] These examples are for illustrative purposes only and are not intended to unduly limit the appended claims. Numerical ranges and parameters that represent the broad scope of the present disclosure are approximations, but the numerical values set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors resulting from the standard deviation found in their respective test measurements. At the very least, each numerical parameter should be construed in light of the reported number of significant digits and by applying ordinary rounding techniques, but this is not intended to limit the application of the doctrine of equivalents to the claims.

[0063] Test method Test method 1: Robot analysis of peel adhesion strength A 6-axis robot with an end effector consisting of a mechanical gripper attached to a 6-axis force / torque sensor was used to peel a tape sample from a substrate. The substrate was cleaned with a 50 / 50 ratio of isopropyl alcohol and water. The tape was 18 millimeters wide and 200 millimeters long. The tape was placed by hand on a stainless steel substrate and then prepared using a 4.5-pound (2.0 kg), 2-inch (5.1 cm) wide weighted roller, and this tape was rolled down to induce wetting out of the adhesive. The roller was moved at approximately 90 inches per minute (0.0381 meters per second). Next, the robot grasped the edge of the tape and peeled the tape from the substrate at a 90-degree angle at a speed of 90 inches per minute. The force of the tape was collected from the force torque sensor, and statistical measurements including, but not limited to, the average value and standard deviation of the peel adhesion strength were calculated in newtons per meter.

[0064] Tape Peeling End Effector A tape peeling end effector was fabricated to grip tape samples. This design consisted of a mounting plate, a force / torque sensor, a connector plate, and an electromechanical gripping mechanism. The mounting plate was manufactured using 1 / 4-inch (0.64 cm) thick aluminum. The design of the mounting plate included machining holes to match the hole pattern of the robot's tool flange and machining holes at another location on the plate to match the hole pattern on one side of the force / torque sensor. The opposite side of the force / torque sensor was fixed to a connector plate made of 1 / 4-inch thick aluminum, which had holes machined to match the hole pattern of the force / torque sensor. Holes were machined at another location on the connector plate to match the hole pattern on the electromechanical gripping mechanism. The electromechanical gripping mechanism included two opposing linear actuators that move linearly towards each other when electrically actuated. Each linear actuator had a curved aluminum jaw attached to it, into which the tape was fed to grip the tape. The end effector was assembled by fastening the mounting plate to the robot's tool flange, fastening the force / torque sensor to the mounting plate, fastening the connector plate to the force / torque sensor, and fastening the electromechanical gripping mechanism to the connector plate.

[0065] Example 1: A 6-axis robot was used to remove a pressure-sensitive adhesive (PSA) tape from a flat glass surface. The adhesive was prepared in the same manner as in Test Method 1, but the removal speed and pitch angle were changed. The results can be seen in Table 1. The peel adhesion strength was obtained by averaging the peel force and dividing it by the adhesive width (0.018 meters). Since the nominal peel front speed was 0.1 meter / second, these values were used to determine the minimum value of the peel adhesion strength of this pressure-sensitive adhesive at a nominal peel front speed of 0.1 meter / second. This was done by fitting a quadratic polynomial to the data and using the gradient descent method to find the minimum value, which was 115.2 degrees and resulted in an average peel adhesion strength value of 245.06 N / m.

[0066]

Table 1

[0067] Example 2: The process described in Example 1 was carried out at several peel pitch angles in the range of 30 to 180 degrees and at several peel front speeds in the range of 0.001 to 1.0 meters per second. The average peel adhesion of the samples was obtained from the force torque sensor, and a two-dimensional manifold was created using the support vector regression algorithm at each point to show the dynamic properties of the average peel adhesion when the peel front speed and pitch changed. Referring to FIG. 5, here, the x (front) axis is the angle, the y (side) axis is the speed, and the z (vertical) axis is the average peel adhesion.

[0068] Hypothetical Example 1: Using a multi-axis robot, the adhesive tape is removed from the two-dimensional manifold while maintaining the minimum average peel adhesion. The robot attempts to maintain the minimum average peel adhesion. If the two-dimensional manifold has a non-uniform surface normal along the desired peel path, it is necessary to update the robot's trajectory to maintain the desired peel pre-angle and speed that result in the minimum average peel adhesion.

[0069] Hypothetical Example 2: While removing the adhesive tape from the two-dimensional manifold, a force may be applied to the adhesive, which may cause deformation of the adhesive tape. If the deformation is too large, the desired peel front angle and speed may not be achieved. Therefore, the robot trajectory is updated according to the deformation of the adhesive tape to maintain the desired peel front angle and speed values.

[0070] Throughout this specification, references to "one embodiment", "a particular embodiment", "one or more embodiments", or "an embodiment" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment are included in at least one embodiment of the specific exemplary embodiments of the present disclosure, whether or not the term "exemplary" is included before the term "embodiment". Thus, throughout this specification, the appearances of the phrases "in one or more embodiments", "in a particular embodiment", "in one embodiment", or "in an embodiment" in various places are not necessarily referring to the same embodiment of the specific exemplary embodiments of the present disclosure. Furthermore, the specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0071] Although specific exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate, upon understanding the foregoing description, that various modifications, variations, and equivalents of these embodiments can be readily conceived. Accordingly, it is to be understood that the present disclosure is not unduly limited to the exemplary embodiments described thus far. In particular, when used herein, a numerical range described by endpoints is intended to include any number within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). In addition, all numbers used herein are assumed to be modified by the term "about". Furthermore, various exemplary embodiments have been described. These embodiments and other embodiments are within the scope of the following claims.

Claims

1. A method for removing a tape attached to an object surface, comprising: preparing a robot including an end effector, wherein the end effector includes a gripping mechanism and a force sensor; initializing the robot and positioning the end effector with respect to the tape on the object surface; gripping an end of the tape by the gripping mechanism; moving the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters; while the end effector moves along the object surface to remove the tape, measuring a peeling force by the force sensor; adjusting a movement trajectory of the end effector to maintain the value of the peeling force within a desired range; determining at least another peeling parameter among the set of peeling parameters based on the peeling force, the determining step including determining at least one of a peeling speed and a peeling angle.

2. The method according to claim 1, wherein the step of determining at least another peeling parameter includes pre-determining a relationship between at least some of the peeling parameters for the tape on the object surface.

3. The method according to claim 2, wherein the pre-determined relationship is a relationship between the peeling force, the peeling speed, and the peeling angle.

4. The method according to claim 1, wherein the step of initializing the robot includes determining a removal path of the tape on the object surface.

5. The method according to claim 4, wherein the step of determining the removal path of the tape on the object surface includes a digital two-dimensional (2D) model or a digital three-dimensional (3D) model of the tape on the object surface.

6. The method according to claim 4, wherein the step of initializing the robot further includes providing an initial movement trajectory that coincides with the removal path of the tape.

7. The method according to claim 1, wherein the step of initializing the robot includes identifying a position of the end of the tape on the object surface.

8. The method according to claim 1, further comprising determining a state of the tape on the object surface.

9. The method according to claim 8, wherein the step of determining the state includes a step of confirming the removal of the tape from the surface of the object.

10. The method according to claim 8, wherein the step of determining the state includes a step of detecting a remaining portion of the tape on the surface of the object.

11. The method according to claim 8, wherein the step of determining the state includes a step of detecting the movement of the surface of the object during the removal of the tape.

12. The method according to claim 8, wherein the step of determining the state includes a step of determining environmental conditions including ambient temperature and ambient humidity.

13. An automated system for removing a tape from an object surface, comprising: an end effector having a gripping mechanism and a force sensor; a vision system having one or more imaging sensors for acquiring imaging data about the tape, the object surface, and the end effector; a controller functionally connected to the end effector and the vision system, wherein the controller: initializes the end effector with respect to the tape on the object surface; grasps an end of the tape by the gripping mechanism; moves the end effector along the object surface to remove the tape from the object surface according to a set of peeling parameters; while the end effector moves along the object surface to remove the tape, measures a peeling force by the force sensor; adjusts a movement trajectory of the end effector to maintain the value of the peeling force within a desired range; is configured to determine at least another peeling parameter of the set of peeling parameters based on the peeling force, the determination including determining at least one of a peeling speed and a peeling angle.

14. The automated system according to claim 13, further comprising a robotic arm, wherein the end effector is attached to the robotic arm.

15. The automated system according to claim 13, wherein the controller is further configured to determine a state of the tape on the object surface based on the imaging data from the vision system.

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