A method for locally controlling the stoichiometry of an epitaxially deposited layer on a semiconductor substrate is provided. When an upper column 11 is fastened on to a vehicle body mounting bracket 3 for tilt and telescopic positioning of the upper column 11, the lower-side telescopic friction plates 61 and upper-side telescopic friction plates 62 are fastened together. A processor receives and processes images acquired by the at least two cameras to detect the existence of a pointer therein and to determine the location of the pointer relative to the touch surface. Motorized joints are actuated to converge both leg braces to a standing stance when the ground force signal indicates leaning on a trailing leg brace.