code: func main() {
  	firmataAdaptor := firmata.NewAdaptor("/dev/tty.usbmodem1451")
  	servo1 := gpio.NewServoDriver(firmataAdaptor, "3")
  	servo2 := gpio.NewServoDriver(firmataAdaptor, "4")
  	servo3 := gpio.NewServoDriver(firmataAdaptor, "5")
  	servo4 := gpio.NewServoDriver(firmataAdaptor, "6")
  	servo5 := gpio.NewServoDriver(firmataAdaptor, "7")
  
  	leapMotionAdaptor := leap.NewAdaptor("127.0.0.1:6437")
  	l := leap.NewDriver(leapMotionAdaptor)
  
  	work := func() {
  		fist := false
  		l.On(leap.MessageEvent, func(data interface{}) {
  			handIsOpen := len(data.(leap.Frame).Pointables) > 0
  			if handIsOpen && fist {
  				servo1.Move(0)
  				servo2.Move(0)
  				servo3.Move(0)
  				servo4.Move(0)
  				servo5.Move(0)
  				fist = false
  			} else if !handIsOpen && !fist {
  				servo1.Move(120)
  				servo2.Move(120)
  				servo3.Move(120)
  				servo4.Move(120)
  				servo5.Move(120)
  				fist = true
  			}
  		})
  	}
  
  	robot := gobot.NewRobot("servoBot",
  		[]gobot.Connection{firmataAdaptor, leapMotionAdaptor},
  		[]gobot.Device{servo1, servo2, servo3, servo4, servo5, l},
  		work,
  	)
  
  	robot.Start()
  }
docs: // Video: https://www.youtube.com/watch?v=ayNMyUfdAqc