The invention relates to a method for sensing a large-deformation space 
pose of a flexible body. The method comprises the following steps of: step 1, arranging three first 
fiber gratings on the outerperipheral surface of a flexible carrier along a 
spiral line, connecting two ends of the flexible carrier with a moving end and a fixed end of a to-be-detected flexible body respectively, enabling thethree first 
fiber gratings to distribute on the same section of the flexible carrier uniformly along the circumference of the section, dividing the flexible carrier into a plurality of sections, andsetting a grid point at each section of the first 
fiber gratings; step 2, calculating 
tensile strain, a 
deflection angle, curvature and a bending angle of each section of the flexible carrier; step 3,substituting the 
deflection angle, the curvature and the bending angle obtained in the step 2 into a rotation 
transformation matrix and a translation 
transformation matrix, acquiring a transformationmatrix between a flexible carrier fixed end coordinate 
system and a flexible carrier moving end coordinate 
system according to the rotation 
transformation matrix and the translation transformation matrix, and acquiring space coordinates of the moving end center and an Euler angle of the moving end surface of the flexible carrier. The sensing method is accurate, efficient and sensitive in response.