Hohmann Transfer Planner

Minimum-fuel orbit raise: fires the first burn only when phase angle and Δv budget align, then sequences coast and circularisation. Every burn proven on-chain.

Category	Aerospace
Template ID	hohmann-transfer-planner
Definition	hohmann_transfer_planner v1.0
States	5 (initial: planning; terminal: arrived)
Transitions	4
Operators composed	HOHMANN_TRANSFER, ORBIT_VELOCITY, THRUST_TSIOLKOVSKY, KO42
Audit clock	on · tick rate 1

What it's for

• Satellite orbit raising
• Constellation station-keeping
• Mission Δv budgeting

States

State	Role
planning	initial
burn1_armed	intermediate
transferring	intermediate
circularising	intermediate
arrived	terminal

Transitions

From	To	Operator	Fires when	Proof	Trigger / actions
planning	burn1_armed	HOHMANN_TRANSFER	input.dv_available_ms >= input.dv_required_ms && input.phase_angle_err_deg < input.phase_tolerance_deg	required	—
burn1_armed	transferring	THRUST_TSIOLKOVSKY	input.burn1_complete == true	required	—
transferring	circularising	ORBIT_VELOCITY	input.at_apoapsis == true	required	—
circularising	arrived	KO42	input.target_orbit_achieved == true	required	—

Operators it composes

Each transition fires a registry operator through the master equation (compute → prove → verify). This template composes:

• HOHMANN_TRANSFER
• ORBIT_VELOCITY
• THRUST_TSIOLKOVSKY
• KO42

Browse the operators at /operators/; the building blocks a transition calls are the framework's protocols. KO42 is the always-on substrate operator; physics operators carry proof_required: true, so each fire runs the full compute → prove → verify path and lands a verifiable proof digest on your entangled state.

Deploy it

Inspect the full definition, then deploy it onto your state machine. Every fire is Zeqond-stamped onto your entangled state.

# 1. Inspect — the full definition (states, transitions, operators) as served
curl -sS https://zeqsdk.com/api/contracts/templates/hohmann-transfer-planner

# 2. Deploy onto your machine (auth: session; body carries your machine slug)
curl -sS -X POST https://zeqsdk.com/api/contracts/templates/hohmann-transfer-planner/deploy \
  -H "Content-Type: application/json" \
  -b "<your session cookie>" \
  -d '{"slug":"<your-machine>"}'
# → 201 { "ok": true, "contract": { "id": "…", "currentState": "planning", … },
#         "template_id": "hohmann-transfer-planner" }

The deploy path runs the same two-stage validation as the canonical create route (ContractDefinitionSchema.parse + validateContractDefinition against the live registry), writes the creation row onto your entangled state, and schedules the first fire. From there, drive transitions with POST /api/chain/<your-machine>/contracts/<id>/transition or let any triggers fire them autonomously.

Next

• Contract IDE — author, preview, and deploy contracts (this template is in the Templates tab).
• State Contracts — the full contract model: conditions, triggers, pre/post actions, lifecycle.
• Templates Library — every ready-to-deploy contract, grouped by category.
• Protocols — the named building blocks a transition composes.