Patent attributes
A robot arm comprising a joint mechanism for articulating one limb of the arm relative to another limb of the arm about two non-parallel rotation axes, the mechanism comprising: an intermediate carrier attached to a first one of the limbs by a first revolute joint having a pitch rotation axis and to a second one of the limbs by a second revolute joint having a yaw rotation axis; a first drive gear disposed about the pitch rotation axis, the first drive gear being fast with the carrier; a second drive gear disposed about the yaw rotation axis, the second drive gear being fast with the second one of the limbs; a first drive shaft for driving the first drive gear to rotate about the pitch rotation axis, the first drive shaft extending along the first one of the limbs and having a first shaft gear thereon, the first shaft gear being arranged to engage the first drive gear; a second drive shaft for driving the second drive gear to rotate about the yaw rotation axis, the second drive shaft extending along the first one of the limbs and having a second shaft gear thereon; and an intermediate gear train borne by the carrier and coupling the second shaft gear to the second drive gear.
