if not keyboard.is_pressed('w') and not keyboard.is_pressed('s') and not keyboard.is_pressed('a') and not keyboard.is_pressed('d'):
                self.setMotorSpeed(0, 0)
                self.speed = 0

            if keyboard.is_pressed('w'):
                self.speed = 0.5
                self.setMotorSpeed(self.speed, self.speed)
                self.isPressedkey = 1
            else:
                if not self.isPressedkey:
                    self.speed = 0
                    self.setMotorSpeed(self.speed, self.speed)
                    self.isPressedkey = 0

            if keyboard.is_pressed('a'):
                self.setMotorSpeed(self.speed - 0.2, self.speed + 0.2)
                self.isPressedkey = 1
            else:
                if not self.isPressedkey:
                    self.setMotorSpeed(0, 0)
                    self.isPressedkey = 0

            if keyboard.is_pressed('d'):
                self.setMotorSpeed(self.speed + 0.2, self.speed - 0.2)
                self.isPressedkey = 1
            else:
                if not self.isPressedkey:
                    self.setMotorSpeed(0, 0)
                    self.isPressedkey = 0

            if keyboard.is_pressed('s'):
                self.speed = -0.5
                self.setMotorSpeed(self.speed, self.speed)
                self.isPressedkey = 1
            else:
                if not self.isPressedkey:
                    self.speed = 0
                    self.setMotorSpeed(self.speed, self.speed)
                    self.isPressedkey = 0