selector sphere


  Transform {
     translation 0 -0.15 0
     children [
        DEF SPHERESENSOR TouchSensor {
        }
  
  
        Shape {
           appearance Appearance {
              material Material {
                 diffuseColor 0 1 0
              }
           }
           geometry Sphere {
              radius 0.05
           }
        }
     ]
  }