private function onEnterFrame(event:Event):void
    {
     walk(segment0, segment1, cycle);
     walk(segment2, segment3, cycle + Math.PI);
     cycle += .05;
    }
    
    private function walk(segA:animation_ch13_Segment, segB:animation_ch13_Segment, cyc:Number):void
    {
     var angleA:Number = Math.sin(cyc) * 45 + 90;
     var angleB:Number = Math.sin(cyc + offset) * 45 + 45;
     segA.rotation = angleA;
     segB.rotation = segA.rotation + angleB;
     segB.x = segA.getPin().x;
     segB.y = segA.getPin().y;
    }
  
   }
  }