A structure method accurately detects biting of a foreign object in a packaging machine. A control apparatus controls a packaging machine that sequentially seals and/or cuts a packaging material transported in a first direction using a rotor. The rotor is arranged to have a tangent to its outer circumference portion in contact with the packaging material extending in the first direction. The rotor is drivable and rotatable by a driver. The control apparatus includes an information obtaining unit that obtains information indicating a rotational position of the rotor and a status value of the driver in predetermined cycles, and a determination unit that determines a presence of an abnormality in a sealed portion of the packaging material using, from the information obtained by the information obtaining unit, a status value of the driver corresponding to a rotational position of the rotor falling within a predetermined range or being a predetermined position.

In described examples of methods and control systems to control a position and/or velocity of a machine, control circuitry is coupled to receive and dither a control signal, and to compute a control output value according to the dithered control signal and a control function. An inverter is coupled to the control circuitry, to control the position and/or velocity according to the control output value.

A motor controller which controls a servo motor for driving a machine, includes: a speed command unit which commands the speed of the machine; a speed detection unit which detects the speed of the servo motor; and a speed control unit which produces a torque command based on a speed command and a motor speed detected so as to control the speed of the servo motor, where the speed control unit includes a filter which approximates the inverse characteristic of a transmission characteristic from the servo motor to the machine, the filter has a transmission characteristic F(s) based on a frequency , a vibration damping coefficient and a cutoff frequency .sub.adj which are adjustment parameters and the frequency is adjusted so as to be equal to or more than an antiresonant frequency .sub.0 of the machine but less than a resonant frequency .sub.p.

A structure accurately detects biting of a foreign object in a packaging machine. A control apparatus controls a packaging machine that sequentially seals and/or cuts a packaging material transported in a first direction using a rotor. The rotor is arranged to have a tangent to its outer circumference portion in contact with the packaging material extending in the first direction. The rotor is drivable and rotatable by a driver. The control apparatus includes an information obtaining unit that obtains information indicating a rotational position of the rotor and a status value of the driver in predetermined cycles, and a determination unit that determines a presence of an abnormality in a sealed portion of the packaging material using, from the information obtained by the information obtaining unit, a status value of the driver corresponding to a rotational position of the rotor falling within a predetermined range or being a predetermined position.

A servo motor controller includes: a servo motor; a driven member which is driven by the servo motor and in which a load acting on a drive axis is varied depending on the position of the driven member; a position detection portion and a speed detection portion for the driven member; and a motor control portion, where the motor control portion includes: a position control portion which calculates a speed command based on a positional error between a position command for the driven member and the position FB; a speed control portion which calculates a torque command by multiplying a speed error between the speed command and the speed FB by a speed gain and/or adding a torque offset to the speed error; and a change portion which changes at least one of the speed gain and the torque offset according to the position of the driven member.

A motor controller which controls a servo motor for driving a machine, includes: a speed command unit which commands the speed of the machine; a speed detection unit which detects the speed of the servo motor; and a speed control unit which produces a torque command based on a speed command and a motor speed detected so as to control the speed of the servo motor, where the speed control unit includes a filter which approximates the inverse characteristic of a transmission characteristic from the servo motor to the machine, the filter has a transmission characteristic F(s) based on a frequency , a vibration damping coefficient and a cutoff frequency .sub.adj which are adjustment parameters and the frequency is adjusted so as to be equal to or more than an antiresonant frequency .sub.0 of the machine but less than a resonant frequency .sub.p.