[en] Accurate measurement of change in tip position and orientation of flexible links is of substantial importance for flexible robot control applications. In this paper, a measurement system is proposed to measure the change in position and orientation at the tip of a link subjected to bending and torsion with the use of position sensitive detector (PSD) sensors for space applications. Contrary to existing methods for measuring the spatial deflection of a flexible robot, the proposed method eliminates the requirement of a fragile lens or prism to obtain the angular displacement when PSD sensors are used. Experimental results for measuring five variables are presented for a cantilever flexible link when subjected to bending and torsion under a static load, thereby demonstrating the effectiveness of the proposed method. (paper)