A stator for a high power density air gap electrical machine comprises an outer annular laminated iron stator core and a stator winding comprising a plurality of coils having linear conductor portions extending substantially parallel to a longitudinal axis of the machine. Certain assurance procedures are automated so that they can be undertaken in real time, in parallel with the generation of the outcome displays on which assurance is being provided. A web crawl is performed on the identified website. The assembly cost and the maintaining cost of the fixture are low, and the assembly and the disassembly of which is simple and timesaving.