An apparatus comprising: a tool system configured to perform an operation at a location on a structure ; and a movement system configured to move the tool system along an elongate frame on the structure to the location , wherein the movement system comprises: a locomotion system configured to move along the elongate frame , the locomotion system comprising: a number of rollers configured to contact the elongate frame ; and a number of motors configured to turn at least one of the number of rollers such that the movement system and the tool system move along the elongate frame ; and a clamping system configured to attach the locomotion system to the elongate frame , the clamping system comprising: a first guide comprising two structures and, on each of the two structures , a bearing comprising a sphere ; a second guide comprising a further structure and two wheel assemblies , each wheel assembly comprising a wheel and a further sphere , the wheel assemblies being configured to contact the elongate frame ; and an engagement system . a tool system configured to perform an operation at a location on a structure ; and a movement system configured to move the tool system along an elongate frame on the structure to the location , wherein the movement system comprises: a locomotion system configured to move along the elongate frame , the locomotion system comprising: a number of rollers configured to contact the elongate frame ; and a number of motors configured to turn at least one of the number of rollers such that the movement system and the tool system move along the elongate frame ; and a clamping system configured to attach the locomotion system to the elongate frame , the clamping system comprising: a first guide comprising two structures and, on each of the two structures , a bearing comprising a sphere ; a second guide comprising a further structure and two wheel assemblies , each wheel assembly comprising a wheel and a further sphere , the wheel assemblies being configured to contact the elongate frame ; and an engagement system . a locomotion system configured to move along the elongate frame , the locomotion system comprising: a number of rollers configured to contact the elongate frame ; and a number of motors configured to turn at least one of the number of rollers such that the movement system and the tool system move along the elongate frame ; and a number of rollers configured to contact the elongate frame ; and a number of motors configured to turn at least one of the number of rollers such that the movement system and the tool system move along the elongate frame ; and a clamping system configured to attach the locomotion system to the elongate frame , the clamping system comprising: a first guide comprising two structures and, on each of the two structures , a bearing comprising a sphere ; a second guide comprising a further structure and two wheel assemblies , each wheel assembly comprising a wheel and a further sphere , the wheel assemblies being configured to contact the elongate frame ; and an engagement system . a first guide comprising two structures and, on each of the two structures , a bearing comprising a sphere ; a second guide comprising a further structure and two wheel assemblies , each wheel assembly comprising a wheel and a further sphere , the wheel assemblies being configured to contact the elongate frame ; and an engagement system . <EOS>