ENKI — AI spacecraft design software for CubeSat missions
Spacecraft design software that runs in your browser. Nothing to install, no licence, free to start. State the mission — orbit, payload, power, link — and ENKI sizes it in front of you, driving HawkLogic's engineering calculators in an agentic loop and recording calculator runs in a live design state you can steer.
// no account needed to start · no card, ever, for the free allowance · calculator runs land in the design state with their full inputs and outputs, on the record
Twenty physics tools — power and mass budgets, link and data budgets, drag decay, propulsion and ADCS sizing, thermal balance, radiation and debris compliance, SGP4 orbit propagation and ground-station passes — wired to the same code that runs HawkLogic's flight trades. The calculations are real runs; the reasoning is shown.
ENKI — the AI spacecraft-design studio
ENKI is an AI spacecraft-design tool for CubeSat and small-satellite missions. You describe the mission in plain language — orbit, payload, power draw, downlink needs — and ENKI does the first-order systems engineering in front of you: it sizes the solar array and battery, budgets mass and data, checks the link, estimates orbital lifetime, and screens the debris-compliance rules that now gate a LEO filing. None of that sizing is arithmetic done in the model's head: it is produced by real calculator runs, each recorded with its full inputs and outputs, so you can open any of them and check the working.
That distinction is the whole design. Large language models are good at reasoning about trades and terrible at arithmetic; deterministic physics code is the opposite. ENKI splits the work: the model decides which calculation to run next and interprets what the result means for your mission, while the calculation itself runs in HawkLogic's unit-tested physics modules — the same code behind the twenty public calculators on this site.
How the agentic loop works
Each turn, ENKI reads your request against the current design state, picks the engineering tools that answer it, and runs them with concrete inputs — often several in sequence, feeding one tool's output into the next (eclipse fraction into the power budget, delta-v into propellant mass). Calculator runs are recorded as artifacts in a live design state you can inspect and steer, and a constraints checker sweeps the whole design each turn, flagging violated margins and inconsistencies between subsystems. Where a picture says it better, ENKI answers with charts, diagrams, and worked math rather than a wall of prose.
A design session, annotated
You — “3U Earth-observation CubeSat, 550 km sun-synchronous. The imager draws 8 W when it's on. Does the power system close, and will it deorbit in time?”
// tool run: eclipse-beta-timeline — worst-case eclipse fraction ≈ 0.36
// tool run: spacecraft-power-budget — required array ≈ 28 W BOL vs ≈ 8 W body-mounted
// tool run: deorbit-compliance — natural lifetime ≈ 9 yr → fails the FCC 5-year rule
ENKI — “Not as described. At a 30% imaging duty cycle your orbit-average load needs roughly a 28 W array at beginning of life — body-mounted 3U panels give you about 8 W, so this bus needs deployable panels or a much leaner duty cycle. And at 550 km your natural decay runs to roughly nine years: plan a disposal burn or drag augmentation. Want me to size the deployables first, or the disposal delta-v?”
// excerpt of a real session shape — three tool runs, a design state updated with three artifacts, and a constraints check, in one turn.
How ENKI compares
Evaluating a systems-engineering suite like Valispace, or high-fidelity astrodynamics like STK or GMAT? ENKI sits earlier in the process — first-order sizing and trades in minutes, in a browser, free to start. It is where you find out whether the mission closes, before you commit to a licence or a full analysis campaign. It does not replace any of them, and it is not meant to: when the design firms up, those tools are where it goes next.
Is ENKI free to use?
Yes — every visitor gets a free allowance of design turns, and signing in with a free HawkLogic account raises it and saves your designs — conversations and their design state persist, so a mission picks up where you left it. No card, no sales call, no demo. The twenty public calculators are free without any allowance at all.
Pions — ENKI's unit of design work
A Pion is the unit ENKI measures design work in, written with the Struck-π mark. It exists because design turns are not all the same size. Asking “what's my eclipse fraction?” is one calculator run and a sentence. Asking ENKI to size a whole 3U bus — orbit, power, mass, link, thermal, compliance, with the trades explained — is a dozen tool runs and a long piece of reasoning. Measured honestly, the heaviest design turns cost tens of times what the lightest ones do.
The usual answer is a flat rate per message, which only balances if the allowance is padded enough to absorb the heavy users — and padding is paid for by the people asking small questions. We would rather meter the work. A Pion is denominated in the computation a turn actually consumes, so a quick sanity check costs a little and a full mission sizing costs what it costs, and neither one is subsidising the other.
The unit you reason in is still the design turn. Wherever your balance appears — in the studio, on your account — it is shown with an estimate of the design turns it still covers, so you never have to convert anything in your head to know where you stand. You can see the balance move as you work, and a turn that consumes nothing costs nothing.
// the free allowance needs no card · the twenty calculators cost no Pions at all · you always see the balance, never a surprise
The calculator library behind ENKI
ENKI's physics registry is built from the same modules that power HawkLogic's twenty public calculators — every one runs standalone in your browser, free, with cited constants and stated assumptions:
- Spacecraft Power Budget
- Power Budget by Operating Mode
- Spacecraft Mass Budget
- Onboard Data Budget
- Steady-State Thermal Balance
- ADCS Sizing
- Comms Link Budget (rain fade)
- EPFD Screening (NGSO vs. GSO)
- Microwave Power Link Budget (35 GHz)
- Electrodynamic Tether Power
- Delta-V Maneuver Budget
- Propulsion System Sizing
- Ground Track & Pass Predictor
- Eclipse & Beta-Angle Timeline
- LEO Drag & Decay Timeline
- Deorbit Compliance & Orbital Lifetime Calculator
- Reentry Casualty Risk
- Radiation Dose vs. Shielding
- Single-Event-Effect Rate
- Compliance Report Generator
Common questions
Do I need an account?
No. Anonymous sessions work, but they live only in your browser tab. Signed-in users' design threads persist server-side and are resumable from the history panel — close the tab on Tuesday, pick the same design up on Friday.
How accurate are ENKI's numbers?
As accurate as the calculators, because they are the calculators: deterministic, unit-tested physics with constants cited to SMAD, ESA, and NASA references. Calculator runs land in the design state as artifacts, each carrying its full input and output, so the computed figure is always one click away — and when a number matters, that artifact is the authority, not the sentence summarising it — which is how design review works anyway: you check the analysis, not the memo. That makes ENKI a first-order systems-engineering tool — the right instrument for sizing, trades, and feasibility, not a substitute for flight certification or high-fidelity mission analysis.
What missions is ENKI best at?
LEO CubeSat and small-satellite missions are the sweet spot — the tool coverage spans the budgets, links, environments, and debris-compliance checks those missions live and die by. It will happily reason about MEO/GEO radiation environments and transfer burns too; the further you drift from a first-order LEO smallsat, the more ENKI acts as a fast sanity-checker rather than a full designer.
// enki — sumerian god of wisdom and craft. first-order systems engineering, not flight certification. the physics is the same physics our tools pages run.