Profile torque mode

In profile torque mode, a constant torque is generated according to the target torque and the defined torque slope (the rate of change of torque).

../../../../../../_images/trajectory_generator_PT2.png

Output of the generator is the torque demand value (0x6074) which is processed by the torque controller.

Objects configuration

The following objects need to be configured for the torque profile:

Note

Target torque is limited by the Object :

Enable Profile torque mode

To enable the mode, the value 4 (0004h) must be entered in object 0x6060. The Op mode display 0x6061 can be used to check if the op mode has been set correctly.

Note

Both enabling the halt bit and setting the target torque to zero will ramp down the torque applied to the motor according to the torque slope. At the end of the slope no torque will be applied to the motor, allowing the shaft to move freely.

Starting/Stopping Torque

To start and stop motion, toggle the controlword halt bit (bit 8). When the halt bit is set to 0, motion will start or continue; when the halt bit is set to 1, motion will stop. The bit can be toggled by writing 010Fh and 000Fh to controlword (object 0x6040).

Operation Mode dependent Bits of Status- and Controlword

Controlword

The torque position mode uses some bits of the controlword for mode specific purposes which are indicated in yellow. The figure shows the structure of the controlword. For the general structure and usage, please refer to our Application note on Status- and Controlword.

15-9 8 7-4 3-0
N/A Halt N/A basic
  • Halt: Both enabling the halt bit or setting the target torque to zero will ramp down the torque applied to the motor according to the torque slope object (0x6087). At the end of the slope, no torque will be applied to the motor, allowing the shaft to move freely.

Statusword

The mode specific bits of the statusword can be used to monitor the performance of the operation. For further information please refer to the section on Control Supervision.

15-12 11 10 9-8 7-0
N/A Internal limit active Target reached N/A basic
  • Internal limit active:

  • Target reached: the bit is set if the actual torque stays in the window of target torque ± torque window value for a duration of torque window time.

Objects related to the bit 10 of the statusword:

Torque window value 0x606D Torque window time 0x606E