Provided is a control device capable of automatically determining whether or not an inertia estimation function needs to be activated. The control device 10 is for an electric motor and comprises: a first inertia estimation unit 11 that estimates whether or not there has been a change in the inertia of an object to be driven, on the basis of at least one among first information pertaining to an operation program or operation settings for a device comprising the electric motor, second information obtained from a detection device for detecting the shape of the object to be driven by the electric motor, and third information indicating the operation state of the electric motor; and a second inertia estimation unit 12 that estimates the inertia of the object to be driven if the first inertia estimation unit 11 has estimated that there has been a change in the inertia of the object to be driven.

Provided is a control device capable of automatically determining whether or not an inertia estimation function needs to be activated. The control device 10 is for an electric motor and comprises: a first inertia estimation unit 11 that estimates whether or not there has been a change in the inertia of an object to be driven, on the basis of at least one among first information pertaining to an operation program or operation settings for a device comprising the electric motor, second information obtained from a detection device for detecting the shape of the object to be driven by the electric motor, and third information indicating the operation state of the electric motor; and a second inertia estimation unit 12 that estimates the inertia of the object to be driven if the first inertia estimation unit 11 has estimated that there has been a change in the inertia of the object to be driven.

A control system may include: a motor configured to power a driven object; and circuitry configured to: generate a first driving force command to drive the motor during a first control; estimate a first force acting on the motor during the first control based, at least in part, on the first driving force command; generate a second driving force command to drive the motor during a second control after the first control; estimate a second force acting on the motor during the second control based, at least in part, on the second driving force command; and estimate an external force acting on the driven object during the second control based, at least in part, on a comparison between the first force and the second force.

A safety apparatus and method for monitoring the position of a servo joint in a servo joint driving system are introduced. The safety apparatus includes modules for measuring powerline signals to determine a servo motor position and/or speed safely. By analyzing the synchronization between the motor and powerline signals, loss of synchronization, unexpected resistance experienced by the motor, and other fault conditions are detected so that power can be cut from the servo motor for safety. The safety apparatus and method achieve a functional safety position and/or speed generating and monitoring and reduce reliance on expensive position sensors and encoders. Robots utilizing the safety apparatus and a method of its use are also disclosed.

A safety apparatus and method for monitoring the position of a servo joint in a servo joint driving system are introduced. The safety apparatus includes modules for measuring powerline signals to determine a servo motor position and/or speed safely. By analyzing the synchronization between the motor and powerline signals, loss of synchronization, unexpected resistance experienced by the motor, and other fault conditions are detected so that power can be cut from the servo motor for safety. The safety apparatus and method achieve a functional safety position and/or speed generating and monitoring and reduce reliance on expensive position sensors and encoders. Robots utilizing the safety apparatus and a method of its use are also disclosed.

A closed loop control system for controlling a plant comprises a controller includes an input arranged to receive a feedback signal from the plant. The controller is arranged to compare a value of the feedback signal to a set point value x(s) and to produce an error signal ε(s) that is at least partially dependent on a difference between the value of the feedback signal and the set point value. The controller also includes an output arranged to supply the error signal ε(s) to the plant. A monitor is arranged to compare a value of the error signal ε(s) produced by the controller to a threshold value and to produce a warning signal when the value of the error signal ε(s) exceeds the threshold value for a period of time greater than a predetermined period.

A safety module for a secured drive control of an automated drive system is configured to receive encoder data sent from an encoder unit to a drive unit, based on an encoder protocol via a protocol active unit. The safety module is configured to forward the encoder data from the protocol active unit to a safety logic and a protocol passive unit, check the forwarded encoder data with the aid of the safety logic for correspondence with predetermined safety criteria relating to operation of a motor unit, and transmit the forwarded encoder data via the protocol passive unit to the drive unit, in respective data packets based on the encoder protocol. The safety module can stop operation of the motor unit with the aid of the safety logic, if the encoder data does not correspond to the predetermined safety criteria. A corresponding drive system and automation system are also provided.

A malfunction determination method for a production machine including a motor as a driving source of a rotating mechanism acquires sensor data of a sensor for detecting a condition of the production machine, determines whether the production machine has an operation stop period during which the production machine has stopped its operation for a predetermined period of time or longer in accordance with an operation history of the production machine, sets a malfunction determination suspension period for suspending a malfunction determination of the production machine when determined to have the operation stop period, in accordance with a length of the operation stop period, and determines whether the production machine has a malfunction in a period other than the malfunction determination suspension period.

A method for monitoring acceleration of a number A of axes of a multi-axis kinematic system utilizes a sampling process with a first sampling interval, wherein a first acceleration limit value assigned to the first sampling interval and a second different acceleration limit value is determined for the acceleration, where a second time interval is assigned to the second acceleration limit value, a plurality of position values of the axis is determined by sampling with the first sampling interval, a current acceleration is calculated via the ascertained position values, and the calculated current acceleration is monitored via a first instance of monitoring utilizing the first acceleration limit value and the assigned first sampling interval and, simultaneously, via a second instance of monitoring utilizing the second acceleration limit value and the assigned second time interval, such that acceleration of an axis is monitored using at least two acceleration limit values simultaneously.

A method for controlling a cutting tool in a CNC machine and a device using the method receives contours of workpieces generated by a first measuring machine, inputs the first contour parameters into a calculation model to output first compensation values of the cutting tool, the calculation model being a time sequences model established according to contour sets of the workpieces, and the contour sets include at least one historical contour of the workpieces. The device further determines whether the first compensation values of the cutting tool are greater than, equal to or smaller than a preset value, and sends the first compensation values of the cutting tool to a machine.