Kinematic design for robotic arm

A method comprising:

• actuating a first rotational joint to rotate a first end effector of a robotic device to a first orientation, wherein the first end effector is connected to a second end of a base linkage through the first rotational joint, and wherein the first rotational joint is configured to rotate the first end effector in a first plane;
• actuating a second rotational joint to rotate a control arm of a robotic device to a second orientation, wherein a first end of a first linkage of the control arm is connected to the second end of the base linkage through the second rotational joint, and wherein the second rotational joint is configured to rotate the control arm in or parallel to the first plane;
• actuating a third rotational joint to align a second end effector with the first end effector based on the first orientation and the second orientation, wherein the second end effector is connected to a second end of a second linkage of the control arm, wherein a first end of the second linkage is connected to a second end of the first linkage through the third actuated rotational joint, and wherein the third actuated rotational joint is configured to rotate the second linkage in or parallel to the first plane;
• and
• actuating a fourth rotational joint to operate the second end effector in coordination with the first end effector, wherein the second end effector is connected to the second end of the second linkage through the fourth rotational joint, and wherein the fourth rotational joint is configured to rotate the second end effector in or parallel to the first plane.

A robotic device comprising:

• a mobile base;
• a base linkage having a first end and a second end, the first end of the base linkage connected to the mobile base;
• a first end effector connected to the second end of the base linkage through a first rotational joint configured to allow the first end effector to rotate in a first plane;
• and
• a control arm comprising:
• a first linkage having a first end and a second end, the first end of the first linkage connected to the second end of the base linkage through a second rotational joint configured to allow the first linkage to rotate in or parallel to the first plane;
• a second linkage having a first end and a second end, the first end of the second linkage connected to the second end of the first linkage through a third rotational joint configured to allow the second linkage to rotate in or parallel to the first plane;
• and
• a second end effector connected to the second end of the second linkage through a fourth rotational joint configured to allow the second end effector to rotate in or parallel to the first plane.