diff --git a/BluetoothControlTank.ino b/BluetoothControlTank.ino
index 3201eba..580c9d8 100644
--- a/BluetoothControlTank.ino
+++ b/BluetoothControlTank.ino
@@ -4,9 +4,13 @@
    5=move forward left, 6=move forward right
    7=move backward left, 8=move backward right
 */
+#include <Servo.h> 
 enum { pinLB = 12, pinLF = 3, pinRB = 13, pinRF = 11 };
+int delay_time = 300;
 int direct = 0;
 
+Servo myservo;
+
 void setup()
 {
   Serial.begin(9600); // define pin for motor output
@@ -14,6 +18,8 @@ void setup()
   pinMode(pinLF, OUTPUT); // pin 3 (PWM)
   pinMode(pinRB, OUTPUT); // pin 13
   pinMode(pinRF, OUTPUT); // pin 11 (PWM)
+  myservo.attach(9);    // Define servo motor output pin to D9 (PWM)
+  handshake();
 }
 
 void loop()
@@ -63,44 +69,56 @@ void backward()
 void turn_right()
 {
   set(LOW, HIGH, 255, 255);
-  delay(300);
+  delay(delay_time);
   stopp();
 }
 
 void turn_left()
 {
   set(HIGH, LOW, 255, 255);
-  delay(300);
+  delay(delay_time);
   stopp();
 }
 void backward_left()
 {
   set(HIGH, LOW, 255, 0);
-  delay(300);
+  delay(delay_time);
   stopp();
 }
 void backward_right()
 {
   set(LOW, HIGH, 0, 255);
-  delay(300);
+  delay(delay_time);
   stopp();
 }
 void forward_left()
 {
   set(LOW, HIGH, 255, 0);
-  delay(300);
+  myservo.write(45);
+  delay(delay_time);
   if (direct == 1)
     forward();
   else
     stopp();
+  myservo.write(90);
 }
 void forward_right()
 {
   set(HIGH, LOW, 0, 255);
-  delay(300);
+  myservo.write(180-45);
+  delay(delay_time);
   if (direct == 1)
     forward();
   else
     stopp();
+  myservo.write(90);
+}
+void handshake()
+{
+  myservo.write(0);
+  delay(delay_time);
+  myservo.write(180);
+  delay(delay_time);
+  myservo.write(90);
 }