Micromanipulation cell probe motion control structure and method

Abstract

The invention belongs to the technical field of cell probes, and particularly relates to a micromanipulation cell probe motion control structure and method.The device comprises a driving mechanism arranged at the output end of a three-axis mechanical arm, the driving mechanism comprises an R driving shaft and a T driving shaft, a cell probe is installed at the output end of the T driving shaft, and the R driving shaft is connected with the T driving shaft. The three-axis mechanical arm and the driving mechanism are electrically connected with an upper computer, and the upper computer controls the movement of the cell probe by controlling the three-axis mechanical arm and the driving mechanism. The method comprises the following steps: electrifying and returning to zero: marking absolute positions of motors of the three-axis mechanical arm and the driving mechanism as zero points; upper computer control: the three-axis mechanical arm and a motor of the driving mechanism are controlled to move through the upper computer; and handle control: a signal generated by the Hall rocker is processed to control a motor corresponding to the driving mechanism to move, and finally the motion control of the cell probe is completed.

Description

Technical Field

[0001] The invention belongs to the technical field of cell probes, and in particular relates to a structure and method for controlling the movement of a micromanipulation cell probe. Background Art

[0002] At present, due to the rapid development of the field of biochemistry, micromanipulation has become an indispensable part of biological experiments. Various micromanipulation devices have appeared on the market, but they are all single-use microscope operating arms, and most of them adopt a stepper motor plus a lead screw structure. After sampling under the microscope, the sampling needle needs to be manually removed and fixed on the mass spectrometer. There is a lack of micromanipulation arms that are compatible with mass spectrometers. Hand shaking during manual operation may cause cells to detach from the probe, and it is easy to introduce dust or other substances from the environment.

[0003] In order to realize the combination of the micromanipulator and the mass spectrometer, it is necessary to ensure that both can operate normally. Under the microscope, at least a three-axis robot is required to control the sampling, and under the mass spectrometer, at least a robot with two degrees of freedom perpendicular to the mass spectrometer port is required. For two machines placed horizontally, these five degrees of freedom cannot be integrated with each other, so at least a five-degree-of-freedom robot is required. At the same time, because the sampling arm is used for cell sampling, the repeatability accuracy must be high enough.

[0004] Existing micromanipulation equipment is a separate microscope operating arm. After sampling under the microscope, the sampling needle needs to be manually removed and fixed on the mass spectrometer. The shaking of the hand during manual operation may cause the cells to separate from the probe, and it is easy to introduce dust or other substances from the environment. In addition, most of the structures used are stepper motors plus lead screws, which cannot avoid the backlash problem caused by the gear structure, resulting in a decrease in the accuracy of the sampling arm. Therefore, the present invention provides a structure and method for motion control of a micromanipulation cell probe. Summary of the invention

[0005] The purpose of the present invention is to provide a structure and method for motion control of a micromanipulation cell probe. The present invention is a five-degree-of-freedom robotic arm, in which the three axes XYZ are orthogonal. The R drive axis and the T drive axis are the other two axes added to the end of the first three-axis robotic arm. Because the first three orthogonal axes are easier to achieve, the R drive axis and the T drive axis installed at the end of the first three axes are mainly discussed. In order to achieve high-precision and backlash-free motion control, a linear transmission solution is innovatively used here to transfer the torque of the direct-drive servo motor to the motion axis, achieving a 38-fold deceleration under zero backlash, and improving the accuracy of the servo motor by 38 times, reaching a repeatable positioning accuracy of 500nm at the end.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A structure for controlling the motion of a micromanipulation cell probe comprises a driving mechanism arranged at the output end of a three-axis mechanical arm, the driving mechanism comprises an R driving shaft and a T driving shaft, the cell probe is installed at the output end of the T driving shaft, the three-axis mechanical arm and the driving mechanism are electrically connected to a host computer, and the host computer completes the motion control of the cell probe by controlling the three-axis mechanical arm and the driving mechanism.

[0008] A method for controlling the motion of a micromanipulation cell probe, the method comprising the following steps:

[0009] Step 1: Power on and return to zero;

[0010] The absolute position of the motor of the three-axis robot and the driving mechanism at this time is marked as the zero point;

[0011] Step 2: Host computer control;

[0012] The host computer controls the motor movement of the three-axis robotic arm and the drive mechanism to control the movement of the cell probe.

[0013] Step 3: Handle control;

[0014] The signal generated by the Hall rocker is processed to control the movement of the motors corresponding to the R drive axis and the T drive axis, ultimately completing the movement control of the cell probe.

[0015] Preferably, the specific steps of step one are as follows: each time the power is turned on, in order to ensure that the probe does not interfere with the microscope and the mass spectrometer, the R drive shaft and the T drive shaft enter the zero return state. When the mechanism triggers the zero point limit switch, the zero return is completed, and the absolute position of the motors of the three-axis robotic arm, the R drive shaft and the T drive shaft at this time is marked as the zero point.

[0016] Preferably, the specific steps in step 2 are as follows: when the cell probe performs sampling and mass spectrometry scanning, the upper computer sends position information through the serial port, and the protocol is a customized 18-byte data, wherein the first 16 bytes of data are valid data, and the last two bytes are CRC fields. After receiving the data, the lower computer first performs a CRC16 check, and then determines the limit information after the check passes. If it is currently in a limit state, the data in the direction of the sampling arm away from the zero point will be sent to the motor, and the data close to the zero point will be discarded, and the error flag will be configured to reach the limit state; if it is not in a limit state, the motor movement of the three-axis robotic arm, the R drive axis and the T drive axis is directly controlled.

[0017] Preferably, in the step 2, when the cell probe is sampling, a very stable end is required, so the innovative R drive shaft and the T drive shaft enter a locking mode. In the locking mode, the servo motors of the R drive shaft and the T drive shaft work in a torque mode, and the motors press the R drive shaft and the T drive shaft to the zero point with a corresponding torque, thereby avoiding the influence of the free shaft on the end of the sampling needle, and this solution does not require a separate mechanical structure, thereby simplifying the mechanical structure and reducing costs;

[0018] When the cell probe is performing mass spectrometry scanning, the requirements for end jitter are not so high, and the motor movements of the three-axis robotic arm, the R drive axis, and the T drive axis can be controlled in a conventional manner.

[0019] Preferably, the step three includes the following specific steps: in the handle control mode, the single chip microcomputer ADC collects the voltage of the Hall rocker, the ADC raw data range is 0-4096, and when there is no operation, it is 2048, and 2028-2068 is defined as the no operation interval;

[0020] In order to prevent accidental erroneous signals from causing terminal jitter, the data collected by ADC needs to be processed. First, the data credibility is judged. That is, if the data is not in the no-operation interval for more than 10 times in a row, the data is considered to be valid data, and then low-pass filtering is performed to smooth the waveform. The processed data is not directly applied to the motor, and limit judgment is also performed. Only when the current R drive shaft and T drive shaft are not at zero position will the data be transmitted to the corresponding servo motor to control the corresponding servo movement.

[0021] The technical effects achieved by the present invention are:

[0022] The present invention is a five-degree-of-freedom robotic arm, in which the three axes XYZ are orthogonal to each other. The R drive axis and the T drive axis are the other two axes added to the end of the first three-axis robotic arm. Because the first three orthogonal axes are easier to realize, the R drive axis and the T drive axis installed at the end of the first three axes are mainly discussed. In order to achieve high-precision and backlash-free motion control, an innovative linear transmission solution is used here to transmit the torque of the direct-drive servo motor to the motion axis, achieving a 38-fold deceleration under zero backlash, and improving the accuracy of the servo motor by 38 times, achieving a repeatable positioning accuracy of 500nm at the end.

[0023] In the present invention, a linear transmission deceleration structure is used on a high-precision micromanipulator arm; a host computer is used to control the micromanipulator arm using a custom protocol; the locking mode presses the R drive shaft and the T drive shaft to the zero point to ensure that the R drive shaft and the T drive shaft are not affected by environmental vibrations, thereby enhancing the anti-interference ability of the sampling arm.

[0024] In the present invention, the linear transmission deceleration structure is used on the sampling arm to achieve high precision and zero backlash at a very low cost; the locking mode makes the sampling arm insensitive to environmental vibrations and makes the end more stable under the microscope; the whole machine does not require complex algorithms and can run on an extremely low-cost MCU. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a front view of a driving mechanism in a structure for controlling the motion of a micromanipulation cell probe of the present invention;

[0026] Figure 2 It is a top view of a driving mechanism in a structure for controlling the motion of a micromanipulation cell probe of the present invention;

[0027] Figure 3 It is an overall diagram of a driving mechanism in a structure for motion control of a micromanipulation cell probe of the present invention;

[0028] Figure 4 It is a general flow chart of a micromanipulation cell probe motion control method of the present invention.

[0029] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0030] 1. Driving mechanism; 11. R driving shaft; 12. T driving shaft. DETAILED DESCRIPTION

[0031] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0032] like Figure 1-Figure 4 As shown, a structure for motion control of a micromanipulation cell probe includes a driving mechanism 1 arranged at the output end of a three-axis robotic arm, the driving mechanism 1 includes an R driving shaft 11 and a T driving shaft 12, the cell probe is installed at the output end of the T driving shaft 12, the three-axis robotic arm and the driving mechanism 1 are electrically connected to a host computer, and the host computer completes the motion control of the cell probe by controlling the three-axis robotic arm and the driving mechanism 1.

[0033] The present invention is a five-degree-of-freedom robot arm, the XYZ three axes are orthogonal, and the R drive axis and the T drive axis are the other two axes added to the end of the first three-axis robot arm. Because the first three orthogonal axes are easier to realize, the R drive axis and the T drive axis installed at the end of the first three axes are mainly discussed. The position relationship of these two axes is as follows Figure 1-Figure 3To achieve high-precision and backlash-free motion control, a linear transmission solution is innovatively used here to transmit the torque of the direct-drive servo motor to the motion axis, achieving a 38-fold deceleration with zero backlash, and improving the accuracy of the servo motor by 38 times, reaching a repeatable positioning accuracy of 500nm at the end.

[0034] like Figure 1-Figure 4 As shown, a method for controlling the motion of a micromanipulation cell probe comprises the following steps:

[0035] Step 1: Power on and return to zero;

[0036] The absolute position of the motor of the three-axis robot arm and the driving mechanism 1 at this time is marked as the zero point;

[0037] The specific steps of step one are as follows: each time the power is turned on, in order to ensure that the probe does not interfere with the microscope and mass spectrometer, the R drive shaft 11 and the T drive shaft 12 enter the zero return state. When the mechanism triggers the zero limit switch, the zero return is completed, and the absolute position of the motors of the three-axis robot arm, the R drive shaft 11 and the T drive shaft 12 are marked as the zero point.

[0038] Step 2: Host computer control;

[0039] The upper computer controls the movement of the three-axis robot arm and the motor of the driving mechanism 1 to control the movement of the cell probe;

[0040] The specific steps in step two are as follows: when the cell probe is sampling and mass spectrometry scanning, the upper computer sends the position information through the serial port. The protocol is a custom 18-byte data, of which the first 16 bytes of data are valid data and the last two bits are CRC fields. After receiving the data, the lower computer performs a CRC16 check first, and then judges the limit information after the check passes. If it is currently in a limit state, the data in the direction of the sampling arm away from the zero point will be sent to the motor, and the data close to the zero point will be discarded. At the same time, the error flag is configured to reach the limit state; if it is not in a limit state, the motor movement of the three-axis robot arm, the R drive axis 11 and the T drive axis 12 is directly controlled.

[0041] When the cell probe is sampling, a very stable end is required, so the innovative R drive shaft 11 and T drive shaft 12 enter the locking mode. In the locking mode, the servo motors of the R drive shaft 11 and T drive shaft 12 work in the torque mode. The motors will press the R drive shaft 11 and T drive shaft 12 to the zero point with the corresponding torque, avoiding the influence of the free axis on the end of the sampling needle. In addition, this solution does not require a separate mechanical structure, which simplifies the mechanical structure and reduces costs.

[0042] When the cell probe is performing mass spectrometry scanning, the requirements for end jitter are not so high, and the motor movements of the three-axis robotic arm, the R drive shaft 11, and the T drive shaft 12 can be controlled in a conventional manner.

[0043] Step 3: Handle control;

[0044] The signal generated by the Hall rocker is processed to control the movement of the motors corresponding to the R drive shaft 11 and the T drive shaft 12, and finally complete the movement control of the cell probe.

[0045] Step three includes the following specific steps: in the handle control mode, the MCU ADC collects the voltage of the Hall rocker, the ADC raw data range is 0-4096, and when there is no operation, it is 2048, and 2028-2068 is defined as the no operation interval;

[0046] In order to prevent accidental erroneous signals from causing terminal jitter, the data collected by ADC needs to be processed. First, the data credibility is judged. That is, if the data is not in the no-operation interval for more than 10 times in a row, the data is considered to be valid data, and then low-pass filtering is performed to smooth the waveform. The processed data is not directly applied to the motor, and limit judgment is also performed. Only when the current R drive shaft 11 and T drive shaft 12 are not in zero position will the data be transmitted to the corresponding servo motor to control the corresponding servo movement.

[0047] In the present invention, a linear transmission deceleration structure is used on a high-precision micromanipulator arm; a host computer is used to control the micromanipulator arm using a custom protocol; the locking mode presses the R drive shaft 11 and the T drive shaft 12 to the zero point, ensuring that the R drive shaft 11 and the T drive shaft 12 are not affected by environmental vibrations, thereby enhancing the anti-interference ability of the sampling arm.

[0048] In the present invention, the linear transmission deceleration structure is used on the sampling arm to achieve high precision and zero backlash at a very low cost; the locking mode makes the sampling arm insensitive to environmental vibrations and makes the end more stable under the microscope; the whole machine does not require complex algorithms and can run on an extremely low-cost MCU.

[0049] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A structure for controlling the motion of a micromanipulation cell probe, characterized in that: The invention comprises a driving mechanism (1) arranged at the output end of a three-axis mechanical arm, wherein the driving mechanism (1) comprises an R driving shaft (11) and a T driving shaft (12), and the cell probe is installed at the output end of the T driving shaft (12). The three-axis mechanical arm and the driving mechanism (1) are electrically connected to a host computer, and the host computer controls the movement of the cell probe by controlling the three-axis mechanical arm and the driving mechanism (1).

2. A method for controlling the motion of a micromanipulation cell probe, characterized in that: The cell probe is the cell probe described in claim 1, and the motion control method comprises the following steps: Step 1: Power on and return to zero; The absolute positions of the three-axis robot arm and the motor of the driving mechanism (1) at this time are marked as zero points; Step 2: Host computer control; The upper computer controls the movement of the three-axis robot arm and the motor of the driving mechanism (1) to control the movement of the cell probe; Step 3: Handle control; The signal generated by the Hall rocker is processed to control the movement of the motors corresponding to the R drive shaft (11) and the T drive shaft (12), and finally complete the movement control of the cell probe.

3. A method for controlling the motion of a micromanipulation cell probe according to claim 2, characterized in that: The specific steps of step one are as follows: each time the power is turned on, the R drive shaft (11) and the T drive shaft (12) enter the zero return state, and when the mechanism triggers the limit switch of the zero point, the zero return is completed, and the absolute positions of the motors of the three-axis robot arm, the R drive shaft (11) and the T drive shaft (12) at this time are marked as the zero point.

4. A method for controlling the motion of a micromanipulation cell probe according to claim 2, characterized in that: The specific steps in step 2 are as follows: when the cell probe performs sampling and mass spectrometry scanning, the host computer sends position information through the serial port, and the protocol is a customized 18-byte data, wherein the first 16 bytes of data are valid data, and the last two bytes are CRC fields. After receiving the data, the lower computer first performs a CRC16 check, and then determines the limit information after the check passes. If it is currently in a limit state, the data in the direction of the sampling arm away from the zero point will be sent to the motor, and the data close to the zero point will be discarded, and the error flag will be configured to reach the limit state; if it is not in a limit state, the motor movement of the three-axis robot arm, the R drive shaft (11) and the T drive shaft (12) is directly controlled.

5. A method for controlling the motion of a micromanipulation cell probe according to claim 4, characterized in that: In the step 2, when the cell probe is sampling, the R drive shaft (11) and the T drive shaft (12) enter a locking mode. In the locking mode, the servo motors of the R drive shaft (11) and the T drive shaft (12) work in a torque mode, and the motors press the R drive shaft (11) and the T drive shaft (12) to the zero point with a corresponding torque; When the cell probe performs mass spectrometry scanning, the motor movements of the three-axis robotic arm, the R drive axis (11) and the T drive axis (12) are controlled in a conventional manner.

6. A method for controlling the motion of a micromanipulation cell probe according to claim 2, characterized in that: The step three includes the following specific steps: in the handle control mode, the single chip microcomputer ADC collects the voltage of the Hall rocker, the ADC raw data range is 0-4096, and when there is no operation, it is 2048, and 2028-2068 is defined as the no operation interval; The data collected by ADC is processed to determine the credibility of the data first, that is, if the data is not in the no-operation interval for more than 10 consecutive times, the data is considered to be valid data, and then low-pass filtering is performed to smooth the waveform; the processed data is used for limit judgment, and only when the current R drive shaft (11) and T drive shaft (12) are not at zero position will the data be transmitted to the corresponding servo motor to control the corresponding private servo movement.

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