Sends CMDVel.

        @param vel: CMDVel to publish

        @type vel: CMDVel

def sendCMD (self, vel):
        '''
        Sends CMDVel.

        @param vel: CMDVel to publish

        @type vel: CMDVel

        '''
        self.lock.acquire()
        self.vel = vel
        self.lock.release()