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Proceedings of IMECE2005 1 Copyright © 2005 by ASME ested. The paper discusses the benefits and some of the issues hat need to be addressed by this approach. Significant areas of oncern include link design and tolerancing issues. NTRODUCTION One of the principal challenges in constructing working rototypes of spatial mechanisms is the large amount of custom esign and machining for each individual assembly. We are uilding multiple testable prototypes in pursuit of automated ssembly uses for low degree-of-freedom spatial mechanisms, ith particular interest in the spherical four-bar. The tests are ntended to compare actual performance and control methods to heoretical values [2][3][10]. As a result, we have developed a ethod for economically and quickly constructing a spherical our-bar. This method will build a mechanism with the interior ngles and initial joint axes that define the kinematics. It is ssumed that the particular angle and axes have been etermined by a separate synthesis method. From the initial ata, a procedure is followed which produces mechanical rawings based on standardized elements. The elements are esigned for ease of manufacture on a standard 2-axis mill, ven without CNC capabilities. The final product is a functional spherical four-bar echanism. The mechanism has a smooth motion profile with assembly tasks that would otherwise be completed by a robot. Ruth and McCarthy [9] demonstrated the versatility of a spherical four-bar (s4R) by showing that it can be used to move an object to four specified orientations. Tse and Larochelle [11] showed how spherical mechanisms may be used to solve spherical approximations of general spatial tasks. Larochelle e