Button location and recognition method for elevator based on artificial mark and geometric transformation

A button location and recognition method is proposed to help robot locate elevator button with the purpose of taking elevator to the destination floor autonomously. The position of elevator’s control panel is determined with four artificial marks around it, while the marks are located by analyzing the nested contours. After transforming the button panel into a rectangle with perspective transformation, we extract the feature of the buttons using morphology transformations. Then the layout of the button panel is determined with the projection histograms of the panel. Finally, the position and function of each button is obtained by comparing the layout with the template that has been set manually.