1. Comments by Independent Reviewer (page limit – 1)
In the system overview diagram, voltage supply buses are missing. The team shall also state the
communications interface that shall be used between the subsystems.
The selected payload mission, although acceptable, is relatively simple. The team is advised to
explore more potential applications that the Arducam could provide.
In the modes of operations, the team is missing the essential transmission mode as it is needed for
establishing communication between the satellite and the ground station. It cannot be implemented
as part of the safe mode. In a mode, the system is either activated or not activated – “occasionally
on” can only be achieved through the selection of the active mode. Moreover, a flowchart showing
the transition between each individual mode shall be given.
The mass budget is reasonably and adequately completed. In the power budget, however, some
values are quite unusual. For instance, while the team has selected “5 x 0.8 W solar panels”, the
power generated is 4 Watts. This is only possible if all 5 solar panels are simultaneously facing the
sun and is, of course, not possible in practice. In the meantime, a power consumption of the Arduino
of up to 1.75 W is unusually high. The aforementioned power consumption/generated values shall
be revised by the team.
In the power budget, the “Arduino” under the ADCS controller should be the Ardupilot. Also, a
power consumption of 0.008W for this component is an unrealistically small number. Moreover, for
the communication board, the “transmit” power of 0.1 Watts is only the power that is converted
into RF for transmission. The total power consumption is higher than this and can be seen in the
datasheet for the selected component. The team shall revise the power consumptions of each
component that is listed in the power budget.
In sentence 4 of the pointing budget, “The Satellite’s position” shall be changed to “The satellite’s
attitude”. The description in the associated paragraph is clearly referring to attitude control and not
position control. More importantly, the team shall also include calculations that prove the satellite
can stabilize its attitude as required in R1.2.1 of the requirements document.
In the attitude sensing error calculations, the magnetorquer ‘s error shall be omitted since it is not a
sensing component. Otherwise, the methodology is adequate.
The data budget shall be based on the satellite scenario and not the high altitude balloon. Even in
the high altitude balloon case, the “satellite” is not necessarily “overhead 100% of the time” since
the balloon will also drift horizontally. Moreover, 10kb/s is not a standard baud rate – The team is
advised to use 9600 b/s instead. More effort shall be placed in the estimation of the data budget.
Link budget calculations shall be moved to the appendix. There are also some “Unknown” and “?”
placed in some of the fields in the uplink budget which should have been estimated.
In the project and planning section, responsibility refers to the assignment of the stated tasks to
individual members of the team. In the Gantt chart, the team shall also separate the “Design and
Prototyping” tasks into two separate tasks with different timelines.
The reference list is weak and inadequate. The team shall include references on the datasheets for
the selected components, especially those of which data was extracted for calculations in the
document.