The present invention provides a compound of formula I;a method for manufacturing the compounds of the invention, and its therapeutic uses. The protrusion of the supporting member may be disposed within the opening. The robot controller rearranges the sequences, in which the robot performs the operation on each work. The server generates information to be shown in the auxiliary display unit, and uses a shared encryption key of the auxiliary display unit to encrypt the information. An angular setting guide is used to select or set the desired angle of use and an articulating lever attached to the removeable torso support provides an arm for stopping or setting the removeable torso support at the selected angle of use by the user.