In The Control System Of Window Cleaning Machine, There Is A Relative Position Between Window Cleaning Machine And Visual Cleaning Unit, And The Determination Of This Position Is A Key Problem To Be Solved. When Determining The Relative Position, It Can Be Divided Into Two Steps: 1. Window Cleaning Machine Finds The Scrubbed Unit. 2. After The Window Cleaning Machine Finds The Scrubbed Unit, First Of All, It Must Accurately Determine The Relative Position And Provide The Necessary Data Parameters. These Two Steps Are Assisted By Two Sets Of Vision Systems. There Are Two Cameras On The Window Cleaning Machine, One Is Ordinary Camera, The Other Is CCD Camera. The Signal Of Ordinary Camera Is Connected With Black-and-white Monitor. There Is A Fixed "ten" Line On The Monitor. When The Staff On The Ground Manually Controls The Window Cleaning Machine To Find The Scrubbed Unit By Using Black-and-white Monitor, They Can Use "ten" To Align With The Edge Of The Scrubbed Unit To Determine The Position Of The Scrubbed Unit And The Window Cleaner, The Error Will Not Exceed 50 Mm. Then, To Locate The Position, Convert The Signal Of The CCD Camera From The Image To The Digital Signal, And Then Use The Computer For Post-processing To Get The Accurate Position, So The Error Will Not Exceed 3 Mm.