Rover Requirement Derivation¶
How the mission requirements flow down to the subsystems, what refines them, and where the flow-down ends without a part to satisfy it.
Lineage¶
Every requirement with its parent, children, descendant count, refinements and satisfiers
| shortName | name | derivedFrom | derives | descendants | refinedBy | satisfiedBy |
|---|---|---|---|---|---|---|
| M-1 | range | dailyRange, energyBudget | 4 | |||
| M-2 | lifetime | nightSurvival | 2 | |||
| S-1 | dailyRange | range | 0 | |||
| S-2 | energyBudget | range | batteryCapacity, driveEfficiency | 2 | EnergyBudgetAnalysis | |
| S-3 | nightSurvival | lifetime | batteryHeater | 1 | ||
| B-1 | batteryCapacity | energyBudget | 0 | battery | ||
| B-2 | batteryHeater | nightSurvival | 0 | HeaterLoop | ||
| D-1 | driveEfficiency | energyBudget | 0 | drive |
Following a chain¶
Everything derived from M-1, at any depth
| shortName | name | documentation |
|---|---|---|
| S-1 | dailyRange | The rover shall drive 500 m per sol. |
| S-2 | energyBudget | The rover shall store 1.2 kWh for each sol's drive. |
| B-1 | batteryCapacity | The battery shall hold 1.5 kWh. |
| D-1 | driveEfficiency | The drive shall convert 85 percent of electrical energy to motion. |
Derived directly from M-1
| shortName | name | documentation |
|---|---|---|
| S-1 | dailyRange | The rover shall drive 500 m per sol. |
| S-2 | energyBudget | The rover shall store 1.2 kWh for each sol's drive. |
The chain above B-1
| shortName | name | documentation |
|---|---|---|
| S-2 | energyBudget | The rover shall store 1.2 kWh for each sol's drive. |
| M-1 | range | The rover shall traverse 20 km over the mission. |
Chain ends¶
Requirements at the top of a chain
| shortName | name | documentation |
|---|---|---|
| M-1 | range | The rover shall traverse 20 km over the mission. |
| M-2 | lifetime | The rover shall operate for 90 sols. |
Leaves no part satisfies
| shortName | name | documentation |
|---|---|---|
| S-1 | dailyRange | The rover shall drive 500 m per sol. |
| B-2 | batteryHeater | The battery shall be kept above -20 C. |