RU169864U1 - Copy manipulator driver - Google Patents

Abstract

The claimed utility model relates to the field of robotics and can be used to create copy manipulators. The claimed master device comprises a shoulder, a forearm and a hand connected to each other by means of corresponding rotational pairs. Rotational pairs are equipped with angle sensors and rotary drives. Data from the angle sensors is transmitted to a functional element that compares this data with the corresponding data of the actuator. Based on the results of the comparison, the functional element generates a signal for rotary drives proportional to the data difference. The technical result consists in providing feedback without impairing other characteristics of the device. f-ly, 6 ill.

Description

The utility model relates to the field of robotics and can be used to create master systems of copying manipulators, including control systems of anthropomorphic robots.

Copying manipulators - systems that consist of two mechanisms - master and executive, the so-called master-slave device. Such manipulators are necessary mainly for work in conditions dangerous to the life of the human body, for example, in areas of high temperatures, radiation, chemically active environments, etc. The master mechanism is usually a device with a kinematic diagram similar to that of a manipulator, and is mounted on the body of the operator. Tracking mechanisms track the movements of the operator and transmit them to the actuator - the manipulator itself.

The use of such systems looks especially promising especially when developing control systems for anthropomorphic (humanoid) robots. Robots controlled in this way could potentially replace people in such dangerous activities as putting out fires, working with hazardous materials, rescue operations, working in outer space and many others. The advantage of anthropomorphic robots in this case is that a two-legged, two-armed robot with a kinematic scheme similar to a human one is able to work in buildings or with equipment originally intended for humans. Another advantage is the ease of control due to the robot circuit, similar to the kinematic diagram of the human body, the operator can, for example, using augmented reality systems to control the robot as if he himself performs all the actions.

It is extremely important when creating copying manipulators is the issue of providing feedback from the manipulator to the operator. This becomes especially relevant when working with brittle or hazardous materials in the absence of direct visibility by the operator of the manipulator's actions. Indeed, given the great potential force embedded in the mechanisms of the actuator, if the operator cannot feel the obstacles, material damage is possible.

One of the possible solutions to this problem is the use of force sensors, most often spring dynamometers. An example of the implementation of such solutions is, for example, the solution disclosed in international application WO 2004026540 A1, publ. 04/01/2004. However, this approach has a number of significant drawbacks. Firstly, dynamometers (especially spring ones) have a rather high threshold of sensitivity, which limits their scope. Secondly, the use of additional spring systems significantly complicates the design of the actuator and does not allow the implementation of an anthropomorphic robot circuit.

Another possible approach may be the use of contact sensors (for example, solutions according to the patents JP 2002059380 A and US 4302138 A), including capacitive or piezoelectric. This approach allows us to solve the feedback problem without overloading the kinematic circuit of the master device with a large number of springs, and also significantly reduce the upper sensitivity threshold. However, contact sensors are quite vulnerable when working with aggressive environments. Also, in the case, for example, of working with dirty materials, it is possible to cover the sensor with a significant decrease in its sensitivity. Another disadvantage of this approach is that the sensitive area is limited by the number of sensors. Thus, to ensure the proper level of feedback, it is necessary (for large anthropomorphic robots the size of a person) an extremely large number of sensors, which complicates the manufacturing and maintenance process, and also reduces the overall reliability of the system.

Separately, it is worth considering the existing options for directly setting mechanisms.

The prior art solution is known - HUMAN BODY MOTION REPRODUCING DEVICE (JP H0 7299773 A, publ. 11/14/1995). The device includes motion sensors and dynamometers. With the help of motion sensors, the operator’s movements are recorded, with the help of dynamometers the force applied by the operator is measured. Data is processed and transmitted to the actuator. Such a driver is difficult to implement because of the complexity of manufacturing and using multiple motion sensors. Also, such a design of the driving mechanism does not allow for feedback.

The prior art knows a solution of a different type - Hand position / measurement control system (US 4986280 A, publ. 22.01.1991). The described device is a series of links interconnected and fixed to the operator’s brush. To determine the movement, as well as the force applied by the operator, angular Hall sensors are used. The device allows you to accurately determine the strength and direction of movement of the operator, however, feedback is not implemented.

The objective of this utility model is to create a driver with feedback, devoid of the disadvantages inherent in known analogues. Moreover, such a device should be simple to manufacture and maintain, not have an excessive number of sensors, applicable when creating anthropomorphic systems.

The technical result, which is achieved by the implementation of this utility model, is to provide feedback without complicating the design of the master device in the absence of special additional requirements for the executive device.

The achievement of the technical result is achieved by adding to the design of the driver of the copying device a functional element configured to compare the rotation angles of the parts of the driver and the rotation angles of the parts of the actuator received from the actuator. In this case, if the angles of rotation of the parts of the driver are different from the corresponding angles of rotation of the parts of the actuator, the said functional element generates a signal that blocks the further movement of the parts of the driver, which for the operator means the presence of an obstacle.

The above attributes, features and advantages of the present utility model, as well as methods for their achievement will become more clear and understandable after reading the following description of the methods and forms of implementation of the utility model, supplemented by relevant drawings, in which:

FIG. 1 shows schematically kinematic diagrams of a driver and an actuator.

FIG. 2 shows an embodiment of a rotational pair of a shoulder-housing connection of a driver.

FIG. 3 shows an embodiment of a rotational pair of a shoulder-forearm connection of a driver.

FIG. 4 shows one embodiment of a shoulder-forearm connection of an actuator.

FIG. 5 shows one embodiment of a shoulder-actuator connection.

FIG. 6 shows an embodiment of the operation of a functional element by the example of switching the shoulder-forearm joints of the master and actuator.

It is worth noting that for a better understanding of the essence of this utility model, the operation of the claimed master device will be shown on the example of the implementation of a fully copying manipulator, however, it is worthwhile to understand that legal protection for the actuator is not claimed.

The copy manipulator contains a master (1) and an executive (2) device. The master device (1) is mounted on the operator's housing (3) and includes a shoulder (4), a forearm (5) and a wrist (6). The shoulder (4) is connected to the housing (3) by a rotary pair (7) with two rotation axes (8 and 9). The forearm (5) is connected to the shoulder by a rotary pair (10) with the axis of rotation of the coaxial axis of the rotational pair (11), the shoulder (12) is the forearm (13) of the operator. The shoulder (4) is made in the form of two links (14) and (15), interconnected by a translational pair (16). All rotational pairs are equipped with relative motion measuring devices. For a rotary pair (7), these are encoders (17 and 18). For a rotary pair (10), this is an encoder (19). The translational pair is equipped with a linear relative motion sensor (not conventionally shown). Encoders are mounted in rotational pairs and can be made on the basis of magnetic or optical angle sensors. In another embodiment, it is possible to implement angle sensors similar to the solution disclosed in US Pat. No. 4,986,280 A.

The master device (1) is connected to the forearm of the operator (13) through the lodgement (20), which provides the convenience of fixing the master mechanism on the operator’s body and the general convenience of operation, which contributes to the implementation of the main purpose of the master device - work as part of the copy manipulator.

The rotational pairs of the driver (1) are equipped with individual drives in terms of mobility. The rotational pair (7), respectively - by the drive 21 - rotation around the axis (8), by the drive 22 - rotation around the axis (9). Rotational pair (10) - driven (23). To control the actuators (21-23), a functional element (24) is used. Functional element (24) is structurally connected with other elements of the master device using assembly operations. Functional element (24) can be implemented on the basis of an analog signal comparison circuit or on the basis of a programmable logic integrated circuit (FPGA), or on the basis of a microprocessor. In another embodiment, the functional element (24) can be implemented as part of a common control unit, which can be performed as part of a master device.

The actuator (2) in one embodiment is equipped with relative motion sensors (encoders) for each degree of mobility, according to a scheme that is generally similar to that of the driver. For example, in a rotational pair (25) connecting the shoulder (26) and the forearm (27), an encoder (28) is installed. Similarly, the sensors (29 and 30) are installed according to the degrees of mobility (31 and 32) of the rotary pair (33) connecting the shoulder (26) of the actuator (2) with the housing (3).

At the same time, the functional element (24) is configured (i.e., has corresponding connectors and is capable of receiving corresponding signals) of receiving data from sensors of relative rotation angles of the links of the driver (28-30). Also, the functional element (24), in addition to constructive communication with other elements of the driver (1), is informationally connected with the encoders (17-19) of the driver (1). Thus, the functional element (24) receives data on the relative rotation angles of the links of the master device, and is also configured to receive similar data from the actuator - encoders (28-30). In this case, the functional element (24) has the ability to compare the received data from the master (1) and executive (2) devices.

In the process of operation, in the absence of obstacles to the movement of the links of the actuator (2), all the movements of the links of the actuator (2) will obviously be identical to the movements of the driver (1), fixed with a tool holder on the body of the operator. Accordingly, the signals from the encoders (17-19) of the driver (1) and the signals from the encoders (28-30) of the actuator (2), which are fed to the input (34) of the functional element (24), will be identical. When the signals coincide, the functional element (24) does not generate a signal to the drives (21-23) of the driver (1).

In the case when the actuator (2) stumbles upon an obstacle during operation, the operator of the driver (1) does not yet know about it. Thus, the movement of the links of the actuator (2) is stopped (or slowed down), and the movement of the links of the driver (1) continues in the same volume. In this case, obviously, the encoders (28-30) of the actuator (2) begin to transmit to the input (34) of the functional element (24) lower values of the angles of the relative rotation of the links than the encoders (17-19) of the master (1). Thus, the functional element (24) begins to fix the difference in the values of the angles of relative rotation, and, consequently, the spatial position of the links of the master (1) and executive (2) devices. In this case, the functional element (24) begins to generate a signal to the drives (21-23) of the driver (1). Motor drivers of the drives (21-23), for example, the forearm drive (23), in accordance with the error signal received from the element (24), specify a torque directed against the direction of the previous movement, for example, the forearm of the operator (13). The operator feels resistance to movement, for example, with the forearm (13), in proportion to the difference in the readings of the encoders (19 and 28).

In the complete absence of a change in the readings, for example, of the encoder (28), the drive (23) completely blocks the movement of the forearm (5) in the rotational pair (10). The operator perceives this as the achievement by the link (27) of the actuator (2) of the obstacle and the impossibility of further movement. The movement of the operator’s hand stops. In the encoder (19), the formation of control signals to the drive (23) stops and the movement of the forearm (27) stops. Unwanted interaction of forearm and obstacles is excluded, which ensures the safety of the copy manipulator.

Equipping the master device with actuators (21-23) and a functional element (24) allows you to create torques that stop the movement of the operator’s hand, which eliminates the formation of control signals to the actuators of the actuator (2) and the movement of its links. This is ensured by the fact that the functional block (24), based on the analysis of the input readings from the instruments for measuring the relative motion of the encoders (17-19), generates control signals from the output (35) to the drives (21-23).

Thus, the claimed utility model implements feedback. There is no need for a separate modification of the actuator, equipping it with dynamometers or distributing touch sensors on its surface. Feedback is implemented with a very low lower threshold of sensitivity. At the same time, what is important, the feedback value is proportional to the difference in the movement of the master and actuator.

The given example of the implementation of the present utility model and an example of operation as part of the copy manipulator shows the possibility of the fundamental implementation of the claimed utility model, as well as the means and methods for such an implementation. However, other options for the implementation of the claimed formula will be apparent to the skilled person.

Claims (2)

1. The master device of the copy manipulator, made with the possibility of interaction with the executive device of the copy manipulator, having links mounted with the possibility of rotation, and connection with the operator by means of a tool tray, characterized in that it contains a shoulder, forearm and hand, connected by rotational pairs , each of which is equipped with a drive according to the degrees of mobility, a functional element structurally connected to the master device, and installed in rotational pairs ax rotation sensors for each degree of freedom of the corresponding rotational pair, while the functional element is connected with the rotation angle sensors of the rotational pairs and is configured to receive data on the relative rotation angles of its links from the actuator, generating a signal proportional to the difference in the readings of the rotation angle sensors and the corresponding data from the actuator and its transmission to the drives. 2. The master device according to claim 1, characterized in that the shoulder is made in the form of two links connected by a translational pair equipped with a linear motion sensor.

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