<p>In situ machining technology, known for its efficiency, precision and eco-friendliness, is highly valued in aerospace component manufacturing. Hybrid mechanisms with large workspaces are preferable for in situ machining. To offer adequate candidate hybrid configurations for the development of in situ machining equipment, this paper proposes a hybrid mechanism scheme and its original configuration that integrates a pose-adjusting parallel mechanism with a positioning parallel mechanism. Based on the FIS theory, a process for obtaining new configurations by adding redundant terms to the finite screw expressions is proposed, yielding two derived configurations. This enriches the options for selecting new configurations. Utilizing the differential mapping relationship between finite screws and instantaneous screws, the results of the configuration analysis were further generalized to the kinematic inverse solutions and Jacobian matrices of the three configurations. Based on this, the outcomes of configuration innovation are closely integrated with performance modeling, and a Jacobian matrix shared by three configurations is established for the comparative analysis of the kinematic performance of the three configurations. The analysis shows that the third configuration has better kinematic performance. This offers a new choice for developing in situ machining equipment and sets a solid theoretical basis for further research.</p>