摘要:
A digital control [Fig. 2] for a multiaxis robot [Fig. 1] includes a pulse width modulation (PWM) circuit [Fig. 58] which drives the arm joint motors (21-26) through a motor control loop. Pulse width modulated control signals (A1, A2, B1, B2) operate power switches in a power bridge [Fig. 5 or Fig. 11 B] to control the current to each robot joint motor. In addition, the PWM circuit provides time stabilized current sampling [Fig. 12] synchronized to the sampling frequency of position and velocity loops in the robot control. The PWM scheme enables accurate motor current measurement through usage of a single current sense resistor (59 or 63) independent of the number of legs in a power amplifier configuration. This scheme permits commercially available, low cost, power blocks to be used for implementation of robot control system power amplifiers. Moreover, the PWM circuitry may be adapted for controlling either a brush [Fig. 5] or brushless [Fig. 11A] type DC arm joint motor.
摘要:
A completely digital robot control operates at a predetermined sampling rate. The robot arm has a plurality of joints with each driven by an electric brushless or brush-type DC motor which is in turn supplied with drive current by a power amplifier bridge circuit having power switches connected therein to supply motor winding current in the forward or reverse direction. Incremental or absolute encoders and tachometers provide for generating digital position and velocity feedback signals generated synchronously with the sampling rate. Digital motor current feedback signals are also generated synchronously with the sampling rate. Paired position/velocity microprocessors generate torque commands for each of the robot axes at the sampling rate in response to the position commands and the position and velocity feedback signals. Paired torque microprocessors generate motor voltage commands for each of the robot axes at the sampling rate in response to the torque commands and the current feedback signals. Pulse width modulators generate digital motor control signals for each of the robot axes at the sampling rate in response to the voltage commands. The digital control signals for each axis are coupled to control terminals of the corresponding power switches to control on/off switch time and satisfy the motor voltage commands and thereby satisfy the position commands.
摘要:
A digital robot control [Figures 3 and 5] is provided with cascaded position/velocity [Figure 10] and torque [Figure 6] control loops with microprocessor servo controllers in each. Each servo controller includes two microprocessors (202, 204) that operate as a servo engine in providing motion control for six robot axes [Figure 1, 21-26]. One microprocessor (202) is structured to perform data processing and coordination tasks. The other one (204) performs calculation tasks and operates as a slave processor to the first. Also included as part of the robot control is a digital position and velocity feedback system [Figure 13, 810, 812] for multiaxis robot control which employs a circuit [Figure 14, 813] to process robot motor encoder incremental position signals for position change and velocity computations. At low speeds, velocity is computed [Figure 17, 848] from the reciprocal of elapsed time. At higher speeds, velocity is computed (850) from the rate at which incremental position signals are generated.
摘要:
A digital control [Fig. 2] for a multiaxis robot [Fig. 1] includes a pulse width modulation (PWM) circuit [Fig. 58] which drives the arm joint motors (21-26) through a motor control loop. Pulse width modulated control signals (A1, A2, B1, B2) operate power switches in a power bridge [Fig. 5 or Fig. 11 B] to control the current to each robot joint motor. In addition, the PWM circuit provides time stabilized current sampling [Fig. 12] synchronized to the sampling frequency of position and velocity loops in the robot control. The PWM scheme enables accurate motor current measurement through usage of a single current sense resistor (59 or 63) independent of the number of legs in a power amplifier configuration. This scheme permits commercially available, low cost, power blocks to be used for implementation of robot control system power amplifiers. Moreover, the PWM circuitry may be adapted for controlling either a brush [Fig. 5] or brushless [Fig. 11A] type DC arm joint motor.
摘要:
A digital robot control [Figures 3 and 5] is provided with cascaded position/velocity [Figure 10] and torque [Figure 6] control loops with microprocessor servo controllers in each. Each servo controller includes two microprocessors (202, 204) that operate as a servo engine in providing motion control for six robot axes [Figure 1, 21-26]. One microprocessor (202) is structured to perform data processing and coordination tasks. The other one (204) performs calculation tasks and operates as a slave processor to the first. Also included as part of the robot control is a digital position and velocity feedback system [Figure 13, 810, 812] for multiaxis robot control which employs a circuit [Figure 14, 813] to process robot motor encoder incremental position signals for position change and velocity computations. At low speeds, velocity is computed [Figure 17, 848] from the reciprocal of elapsed time. At higher speeds, velocity is computed (850) from the rate at which incremental position signals are generated.
摘要:
A modular digital robot control includes an electronic arm interface board for performing robot arm control dependent functions, an electronic torque processor board with paired microprocessors for operating the respective torque control loops for the robot joint motors, and an electronic servo control board with paired microprocessors for operating position and velocity control loops for the respective joint motors, said electronic boards being interfaced together by a digital bus. A system resource facility is provided for supporting communication between the microprocessors of the various boards and with input/output devices and other systems. A motion program which uses trajectory planning and interpolation to generate position commands In accordance with predefined moves set forth in a robot program is stored on the servo control board in a basic control configuration or is stored on an additional system control board in an expanded control configuration. A communication interface for the paired microprocessors of each board includes first and second memory banks which are cross-switched at a control sampling rate to provide a coordinated exchange of information between its respective pair of microprocessors.
摘要:
A modular digital robot control includes an electronic arm interface board for performing robot arm control dependent functions, an electronic torque processor board with paired microprocessors for operating the respective torque control loops for the robot joint motors, and an electronic servo control board with paired microprocessors for operating position and velocity control loops for the respective joint motors, said electronic boards being interfaced together by a digital bus. A system resource facility is provided for supporting communication between the microprocessors of the various boards and with input/output devices and other systems. A motion program which uses trajectory planning and interpolation to generate position commands In accordance with predefined moves set forth in a robot program is stored on the servo control board in a basic control configuration or is stored on an additional system control board in an expanded control configuration. A communication interface for the paired microprocessors of each board includes first and second memory banks which are cross-switched at a control sampling rate to provide a coordinated exchange of information between its respective pair of microprocessors.
摘要:
A completely digital robot control operates at a predetermined sampling rate. The robot arm has a plurality of joints with each driven by an electric brushless or brush-type DC motor which is in turn supplied with drive current by a power amplifier bridge circuit having power switches connected therein to supply motor winding current in the forward or reverse direction. Incremental or absolute encoders and tachometers provide for generating digital position and velocity feedback signals generated synchronously with the sampling rate. Digital motor current feedback signals are also generated synchronously with the sampling rate. Paired position/velocity microprocessors generate torque commands for each of the robot axes at the sampling rate in response to the position commands and the position and velocity feedback signals. Paired torque microprocessors generate motor voltage commands for each of the robot axes at the sampling rate in response to the torque commands and the current feedback signals. Pulse width modulators generate digital motor control signals for each of the robot axes at the sampling rate in response to the voltage commands. The digital control signals for each axis are coupled to control terminals of the corresponding power switches to control on/off switch time and satisfy the motor voltage commands and thereby satisfy the position commands.