Method for avoiding singularities of robotic arm, control device and computer-readable storage medium

A control device comprising:

• one or more processors;
• and
• a memory coupled to the one or more processors, the memory storing programs that, when executed by the one or more processors, cause performance of operations comprising:
• calculating a virtual environment external force required by a robotic arm to avoid singularities based on current joint positions of joints on the robotic arm when it is determined that the robotic arm needs to avoid singularities;
• obtaining a current end force of the robotic arm and a desired end trajectory of the robotic arm;
• performing admittance control calculation based on the virtual environment external force, the current end force and the desired end trajectory to obtain a corrected end trajectory of the robotic arm;
• and
• controlling the robotic arm to move based on the corrected end trajectory;
• wherein the operations further comprise:
• obtaining the current joint positions of the joints on the robotic arm;
• calculating manipulability of the robotic arm based on the current joint positions;
• and
• determining that the robotic arm needs to avoid singularities in response to the manipulability being less than or equal to a preset threshold;
• and
• wherein calculating the virtual environment external force required by the robotic arm to avoid singularities based on current joint positions of joints on the robotic arm comprises:
• obtaining the manipulability of the robotic arm, wherein the manipulability is determined based on the current joint positions;
• obtaining joint torques required by the robotic arm to avoid singularities based on the manipulability;
• and
• converting equivalently the joint torques into the end force of the robotic arm to obtain the virtual environment external force required by the robotic arm to avoid singularities.

A non-transitory computer-readable storage medium storing instructions that, when executed by at least one processor of a control device, cause the at least one processor to perform a method, the method comprising:

• calculating a virtual environment external force required by the robotic arm to avoid singularities based on current joint positions of joints on the robotic arm when it is determined that the robotic arm needs to avoid singularities;
• obtaining a current end force of the robotic arm and a desired end trajectory of the robotic arm;
• performing admittance control calculation based on the virtual environment external force, the current end force and the desired end trajectory to obtain a corrected end trajectory of the robotic arm;
• and
• controlling the robotic arm to move based on the corrected end trajectory;
• wherein the method further comprises:
• obtaining the current joint positions of the joints on the robotic arm;
• calculating manipulability of the robotic arm based on the current joint positions;
• and
• determining that the robotic arm needs to avoid singularities in response to the manipulability being less than or equal to a preset threshold;
• and
• wherein calculating the virtual environment external force required by the robotic arm to avoid singularities based on current joint positions of joints on the robotic arm comprises:
• obtaining the manipulability of the robotic arm, wherein the manipulability is determined based on the current joint positions;
• obtaining joint torques required by the robotic arm to avoid singularities based on the manipulability;
• and
• converting equivalently the joint torques into the end force of the robotic arm to obtain the virtual environment external force required by the robotic arm to avoid singularities.