بسم الله الرحمن الرحيم

Saad Al-Shammari, Ibrahim Sheerah, Mansour Al-Tubaigi ME 594 ; Design of a Micro-Satellite Structure Using ANSYS Package Supervisor Dr. Khalid Alsaif Mechanical Engg Department, KSU Presented by :

ME 594 :presentation; Design of a Micro-Satellite ….Continued….  To develop a Micro-Satellite (LEO) with a total lower mass than other designs. total lower mass than other designs.  The panels, however, should be easily replaced or re-arranged. replaced or re-arranged. This Satellite can be used for the purpose This Satellite can be used for the purpose of data transmission ;as primary mission of data transmission ;as primary mission and to capture images ; as a secondary and to capture images ; as a secondary mission. mission.

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. What are LEO Satellites? Satellites can be divided into three different categories ; according to their attitude from earth. LEO Satellites (Low Earth Orbit) are usually located between 700 km from the earth to 1500 or 2000 km. The low altitude of the orbit makes the transmission time for a link between a ground station and the satellite much shorter than other satellites.

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Satellite Design Objectives * To Transmit Data from ground Remote Sites to the Testing Laboratories. to the Testing Laboratories. To Capture Images & Videos from certainTo Capture Images & Videos from certain locations on the earth. locations on the earth...For that purpose, our design have to be : Simple.Simple. Cost EffectiveCost Effective Strong Enough,to withstand launching conditions.Strong Enough,to withstand launching conditions. Reasonably Light Weight ;i.e. less than 15 Kg.Reasonably Light Weight ;i.e. less than 15 Kg.

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Payload a small ccd camera (Eagle Technology) Satellite Structure Power Unit Attitude Control Thermal Control Command and Data Handling Telecommunications

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Structural Design Procedure **The following aspects shall be covered: The structural Design should be Strong and Stiff enough ;with Balancing Mass fixations. Design should be Agreed by the Controlling Bodies to permit certification and qualification of structures; The structural Materials should be Reliable, Reproducible and should be able to Resist the Environmental Factors. * Materials used shall Not be Hazardous *Total Mass should be Minimized ; *The structure shall be Cost Effective and manufactured by Reliable and Repeatable methods. * Redundancy should be considered.

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Major Design Requirements for a Microsatellite Structure: could be summarized as follows : Knowledge of the Environment 1- Knowledge of the Environment 2- Simple Structural Lay-out. 3- Simple Access and Assembly. Center of Mass should be very close to the Center of Pressure 4- Center of Mass should be very close to the Center of Pressure 5- I XY, I YZ & I ZX should have Near-Zero Values 6- Shielding of Sensitive Electronic Parts (i.e. VT unit) 7 - Mechanical Decoupling : Simple Interfaces, 8-Taking into account the Thermal Requirements. Choice of Materials 9-Precise Choice of Materials : i. e. Strength – Stiffness - Outgasing, Corrosion - Electromagnetic – Availability- Cost – Radiation Humidity,...

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Design Concept Procedure

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Inner & Outer Views VHF RECEIVER UHF TRANSMITER S-Band TRANSMITER SOLAR CELLS: on all 6 sides:36cell/side PCB BOARDS

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Detailed Design **In order for the design of our Microsatellite to be ready for manufacturing, deatailed drawings for the various parts have been included. Among these are : 1)Bottom ( base) Plate 2)Custom Nut (connecting nut) 3)Side Link 4)Side Plate 5)Strengthen Plate 6)Main Supporting Pipe 7)Top (covering) Plate

Bottom ( base) Plate

Custom Nut

Side Link

Side Plate

Strengthen Plate

Supporting Pipe

Top (covering) Plate

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Finite Element Modeling via ANSYS **The Structural Model of our Microsatellite was first designed & drawn using Mechanical Desktop Software ** The Model was next brought to ANSYS as a DB file **We then followed the Finite Element Analysis steps using ANSYS package (ver.10). ** In the ANSYS analysis, we subjected the model to a Gravity Force of (10 g) due to acceleration of the launching rocket, although a selection of (7g) was also adequate.

QTYNAMEMATERIAL UNIT MASS (GRAMS) TOTAL MASS (GRAMS) 1BACK BOX COVERALUMINUM SCREWALUMINUM TELEMETARY BOXALUMINUM200 4STAND_OFF 6.4 MM HIGHTNAYLON MODEM BOARDFR4 PCB SPACERNAYLON VIDEO TRANSMISSION BOARDFR4 PCB STAND_OFF 4.4 MM HIGHTNAYLON POWER PCBFR4 PCB60 1BATTERY ASSEMBLYASSEMBLY CAMFR4 PCB10 1PIPEALUMINUM STRENGTH PLATEALUMINUM TRANSMETER 484 6LINKALUMINUM SIDEALUMINUM S-PAND ANTENNAANTENNA HOLOW NUTALUMINUM TOP_PLATEALUMINUM ANTENNA RECIEVER SOLAR CELLSSOLAR CELL BOTTOM PLATEALUMINUM SUM (grams) SUM (Kg) MATERIAL PROPERITES

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Static Analysis Using ANSYS Package (ALL PARTS)

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. **Calculating Center of Pressure; C p

ME 594 :presentation; Design of a Micro-Satellite ….Continued….

Static Analysis Using ANSYS Package (WITHOUT SIDE PLATES)

ME 594 :presentation; Design of a Micro-Satellite ….Continued….

Microsatellite Mode Shapes

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Natural Frequencies SET(MODE SHAPE) TIME/FREQ (HZ)

Microsatellite Environmental Testing Prior of being launched to space; micro satellites like all other spacecrafts have to go under Extensive and rigorous Testing Environments to be qualified for their specific missions. Such tests including THERMAL, MODAL,VACUUM& VIBRATION TESTING are needed to satisfy the launch service provider that the satellite will survive the launch environment and it will operate as intended in the Space. Testing & Evaluation of microsatellites follow Certain Steps : 1)Defining Testing Purpose, Strategy& Philosophy. 2) Defining testing Requirements: (a) Type of Tests. (b) Test Levels 3) Developing Contacts for : (a) Gaining Technical Advice (b) Finding Sponsorship. 4) Produce Qualification Testing Plans. 5) Finding Suitable Equipment to Perform the Test. 6) Designing the Test 7) Performing the Test. 8) Evaluating the Performance (pass/fail evaluation).

Microsatellite Model Testing Purpose: To Verify the structural detail Design based on a Finite Element Approach. Two Different Tests ( MODAL Test) Identify three basic elements : (1)Natural Frequencies of the structure (2) Mode Shapes (3)Damping Ratios associated with each mode. If the test correlates well with the finite element model :qualification testing may proceed. Otherwise some adjustments, must be incorporated. ( VIBRATION Test) The Vibration Testing,however, is used to measure the natural frequencies of the structure when it is subjected to random and sinusoidal vibrations in all directions (x, y, z).

ME 594 :presentation; Design of a Micro-Satellite ….Continued…. Microsatellite Concluding Remarks *The total mass of the satellite is about 8.1 Kg which is less than 15 kg as required. The Maximum Stress is 0.4*10^5 Pa, which is far less than modulus of elasticity of aluminum (safe). ALL Natural Frequencies exceeded 20 Hz. * Center of Mass is closed to the Center of Pressure.

QUESTIONS ARE MOST WELLCOMED ! END of PRESENTATION ……