This page explains how to modify the servo gripper to add overcurrent protection.
When the servo gripper is commanded to close on a solid object, the object may prevent the gripper from reaching its target position. In such cases, the servo gripper stalls and consumes maximum current, which can cause it to overheat and become damaged. To prevent this, the servo gripper can be equipped with a current sensor to measure the current flow. The gripper driver can then dynamically adjust the commanded position when overcurrent is detected.
An ACS712 5A current sensor is added to the gripper as shown in the schematic below:
To enable gripper overcurrent protection, set use_overcurrent_protection to
true in the
gripper_driver.yaml
configuration file.
The ACS712 module is available in 3 different versions: 5A, 20A, and 30A. If you have the 20A or 30A version, set ACS712_version_current to 20 or 30 in the
gripper_driver.yaml
configuration file.
Parameters for tuning this feature can be found in gripper_overcurrent_protection.hpp.