Figure 14: Z- Face Figure 15: X+, X-, Y+, Y- Faces Sun Sensor Interface Coarse Sun sensors are mounted on all 6 faces of UNITYSat allowing approximate measurements to determine direction and intensity of the sun. The sun sensors used are redundant as there are two types of sensors on all faces, one digital ambient light sensor and one photodiode operating in photoconductive mode. Connectors placement The Z+ and Z- faces have dedicated connectors for Solar power and for communication with the sun sensor and temperature sensor. The power connector is a 2pin connector capable of supporting a maximum power output of 3.5A per terminal. The Interface connector is a 4 pin connector capable of supporting 3.5A per terminal also. The X+/X-/Y+/Y- faces have two 5 pin connectors which connect all 4 faces parallelly and break out into solar power and communication at one point to connect to the payload interface board and the EPS board separately. Represented in figure below.
Figure 16: Z+ Solar Panel PCB Figure 17: Z- Solar Panel PCB Figure 18: X+, X-, Y+, Y- Solar Panels PCB
STRUCTURAL LOADS Static Structural Acceleration Load Figure 19: Inertial Acceleration Load is Applied at C.G. The Components are [109m/s2, 59m/s2, 0]. Fixed Constraint is Applied on the Bottom Surface of the Four Rails Equivalent Stress (von-Mises) Figure 20: Maximum Equivalent Stress Of 1.0532 Mpa Has Been Observed. Also The Maximum Deformation And Stresses Occurred In The Pcbs (Material FR4). The Tensile Strength Of A Typical PCB Is Greater Than 250 Mpa. Therefore The Maximum Stress From The Simulation Is Less Than The Typical Values
Figure 21: A Total Deformation Of About 0.010623 Mm Was Observed For The Above-Mentioned Loads. The Above Fig. Also Depicts The Location Of The Maximum Deformation MODAL ANALYSIS Total Deformation (Mode 1) Figure 22: The First Modal Frequency Occurred at 490.51 Hz with a Maximum Deformation Value of 0.625m. As per the Stiffness Requirements, the Fundamental Frequency has to be Greater than 135 Hz in Longitudinal Direction and 70 Hz in Lateral Direction. The Maximum Deformation in all the 10 modes Occurred in the PCBs
Total Deformation (Mode 2) Figure 23: The Second Modal Frequency Occurred at 568.77 Hz with a Max. Deformation of 0.472m Total Deformation (Mode 3) Figure 24: Third Modal Frequency of 874.2 Hz with Max. Deformation of 0.622 m
Total Deformation (Mode 4) Figure 25: Fourth Modal Frequency of 916.03 Hz with Max. Deformation of 0.667 m Total Deformation (Mode 5) Figure 26: Fifth Modal Frequency: 1064.1 Hz with Max. Deformation: 0.665 m
Total Deformation (Mode 6) Figure 27: Sixth Modal Frequency: 1081.1 Hz with Max. Deformation of 0.7392 m Total Deformation (Mode 7) Figure 28: Seventh Modal Frequency: 1126.9 Hz with Max. Deformation of 0.612 m
Total Deformation (Mode 8) Figure 29: Eight Modal Frequency: 1264.2 Hz with Max. Deformation of 1.424 m Total Deformation (Mode 9) Figure 30: Ninth Modal Frequency: 1400 Hz with Max. Deformation of 0.767 m
Total Deformation (Mode 10) Figure 31: FIG 16: Tenth Modal Frequency: 1662.3 Hz with Max. Deformation of 0.833 m HARMONIC ANALYSIS Figure 32: Harmonic Analysis was conducted for a Frequency Range of 8-100 Hz. Acceleration Load same as that in Static Structural, has been Applied. A Damping of 1% is given in the Analysis Settings. The Total Deformation Observed is 1.0931e-02 mm
PSLV FLIGHT ENVIRONMENT TESTS Sinusoidal Vibration FREQ. RANGE QUALIFICATION LEVEL ACCEPTANCE LEVEL (Hz) LONGITUDINAL AXIS 5-8 34.5mm DA 23mm DA (PSLV) 8-100 4.5g 3g LATERAL AXIS (PSLV) 5-8 24mm 8-100 3g 16mm SWEEP RATE 2g 2 Oct/min 4 Oct/min Random Vibration Shock Levels 105g, 2ms half sine pulse in vehicle longitudinal axes 70g, 2ms, half sine pulse in vehicle lateral axes One shock per axis per direction Thermo Vacuum 10-5 Torr at 323K for 24 hours UNITYsat Core Team Distinguished Mentors of UNITYsat
Search
