Applications Of Mechatronics In Aviation Engineering Essay

The term Aviation covers all the activities involved building of flying aircraft especially air planes. The two major divisions are manufacturing of air craft and its components, and second airlines operation. This manufacturing includes of space craft, missiles and related electrical and electronic components. This aviation industry subdivided into

Air craft manufacturing

General aviation activities

Airline operation

Airport operation

Aviation support industries

Applications of Mechatronics in Aviation

This essay will discuss about some of the components used in aviation industry which relates to applications of mechatronics.

Aileron

Flaps and Actuator drive unit

Pilot Static system

Fly by wire control system

Yaw damper

Primary flight control system

Internal navigation system

Under carriage

Measurement of motor rpm

Measurement of air flow velocity

Altitude measurement sensor

Air speed

Aileron

This ailerons were mounted by the hinges in a reaction test frames and variety of actuator configurations with adjustable links. Electro dynamic shaker attached with a bonded pad to the outboard closeout rib are used to apply various frequencies and amplitude to the aileron. An accelerometer used to monitor the frequency responses. If the frequencies were comparable the flutter free performance of the composite aileron was predicted. A pair of actuators fixed by the pads to the rear of the ailerons. This is used to load and determine the chordwise bending and torsional rigidity. The movement are measured at nine points on the ailerons were measured by two ways. The two ways are linear transducers and optical.

Flaps

This flaps constructed with parametric computer model and actuator system. The overall model could moved the full range of flap rotation and deflections and it could represent the thermal expansion in both vertical directions and longitudinal. The drive unit rotates in its mounting axis to maintain tangency of the pinion gear and sector gear regardless of any shifts in the location of the flap hinge axis. The existing computer design model is used to determine the real movement at the bearing with the system in a thermally deflected and conform the required movement. This computer model is used to find the sources of interference and eliminates the source. This system is reliable as well as critical for real time determination of components locations in the vehicle. It is very difficult for proper alignment of the parts with out this computer model and drive unit.

Actuator drive unit

This actuator drive unit is designed to create maximum torque and speed if any two electrical or controller failures. Due to

weight concern mechanical redundancy is not provided also it will increase effect of

complexity and overall reliability. To resolve this issue the failsafe design were included into the individual components to improve the reliability concerns. When the motor channel fails the rest of the channel would drag along the failed motor.

Pilot Static System

This pilot static system is mostly used in aircrafts to determine the aircrafts airspeed, Mach number, altitude and altitude trend. This system consists of pilot tube, a static port and pilot static instruments. This unit also measures the external forces acting on the aircraft like temperature, pressure, density and viscosity of the fluid while in operation. Rest of the instruments connected to monitoring computers and data recorders, altitude encoders, cabin pressure controllers and various speed switches. Most of the commercial aircraft disasters have been traced to a failure of the pilot.

Fly by Wire control Systems

This fly by wire control systems is most reliable than manual control of an aircraft. The changes in flight control components are converted to control signal and transmitted to flight control computers by the wires to determine how to move the actuators at each control surface. This flight control computers gives feedback to stabilize the aircraft performance even without pilot knowledge.

Yaw damper

In many air craft usually in jets and turboprobs to decrease the damper due to Dutch roll mode this Yaw damper is used. It includes Yaw rate sensors and processor. This overall unit gives signal to an actuator which is connected to the rudder. The purpose of this yaw damper is to give solution for the better ride to passengers. This component is required in aircraft to ensure the stability stays with in the certified values.

Primary flight control system

This mechanically controlled system design is to provide responds to primary flight control system. For flight envelope protection this electronically system is used. This control system is split into two levels, the four actuator controls and three primary flight computers. This gives warnings to pilot.

In internal navigation system includes motion sensors (accelerometers) and rotation sensors (gyroscopes). This setup is continuously calculating the reckoning position, orientation, and velocity of an aircraft and space craft.

Undercarriage

When take off and landing it allows the aircraft to move as a taxi. This structure compile with wheels, floats and landing gear system. The landing gear is hydraulically rotated forward and up during the ground operations until it engages an uplock hook. This landing gear doors having high temperature reusable surface insulation thermal protection systems tiles joined together with their outer surface.

Characterization setup of motors, batteries and propeller

In Mini and Micro air vehicles the characterization setup module has been using. This set up having motors, batteries and propellers, computer, multifunction I/O card, tachometer, current sensor, air velocity transducer, thermocouple with conditioner and necessary hardware interface. The DC voltage applied to the motor is controlled by LabVIEW based software. This software continuously collects the six channels data, calculates the engineering inputs, as well as keep updating the screen readout and displays the data also save the data into ASCII spreadsheet file. The collected and displayed data includes motor current, voltage, temperature, RPM, air velocity, thrust, calculated instantaneous power and calculated torque.

Measurement of motor RPM

It is important to measure most efficiently motor, propeller and gear box combination RPM. Motor’s rpm based on varying the combinations of the propulsion system’s components. Another important operation is to detect when motor failure happen. For this detection this system applies two methods to design Tachometer. In first method a wiring harness to connect to the existing real time system, magnets and Hall effect sensor on the gears or motor fan. When the fan start to rotates, the Hall effect sensor detects the field magnetism which is developed due to rotation and sends a signal to the board that is having capability to count the pulses. In second method an optics module is focused to illuminate the spinner from the side. When light reflects off a white stripe on the spinner is detected by the photo sensor for each revolution.

Measurement of air flow velocity

By using the thermal anemometry the air velocity transducer measures velocities. This method of measurements offers flexibility with wide ranges for accurate measurements. The simple operation of this arrangement is an electric current passed through in a fine filament which is open to the elements to cross flow. When the air flow varies the transferring heat also varies and it causes a variation in the heat balance of the filament. The fine filament material having a property to hold the temperature co-efficient resistance. This change is monitored via electronic methods and communicate the signal to corresponding flow velocity or flow temperature. This method also used for instantaneous velocities and temperature measurement.

Aircraft altitude measurement sensor

For altitude measurement Piezoresistive silicon sensors are mostly used. Due to high accuracy requirement the monolithic silicon pressure sensors are used and it delivers high level analog output signal is proportional to the applied pressure. In case of change in temperature the silicon sensors are compensated due to these are temperature dependent. This altimeter is used as an absolute sensor. The outcome of the sensor is directed to an operational amplifier. The gain and offset of the amplifier circuit is modifying by two trimmers, so that it can be calibrated.

Air Speed

This differential airspeed pressure sensor output is connected to an operational amplifier. To calibrate the signal gain one of the trimmer is used. The ports of silicon based sensors are static and variable. To determine the outside air pressure Mensor pressure controller was used to apply a standalone pressure to the static port. When increase in the pressure difference between two ports it generates the output voltage. The output voltage are lowest when the pressure is equal also it offset the voltage.