A method for assessing the positioning accuracy of a medical robot arm comprising at least one joint, wherein the rigidity of the robot arm in a joint placement is calculated and assessed on the basis of a rigidity model. The meta data generating method includes receiving emotional information in relation to the content from at least one client system which receives and reproduces the content; generating meta data for an emotion using the emotional information; and coupling the meta data for the emotion to the content. The upper margins of the respective bag walls are joined to the backs of the respective base strips. Thereafter, the group delay for the channel is generated based upon the generated phase response.