An openable ring, cylindrical, or tunnel support frame should be specified as a chain of mechanical states, not as a frame with a nominal gap. The project must define who or what passes through, the complete moving envelope and approach, which frame segment moves, what remains attached, how the load path changes, what temporary support is engaged, how the segment opens and returns, how it seats and relocks, and what evidence permits the restored configuration to be used.
Start with one Frame Configuration ID, one Opening Segment ID, and one Passage Task ID. Tie them to current drawings, the frame and base state, supported-item and obstruction revisions, the person or equipment input, the opening interface, temporary support, project-defined transition steps, relocking method, mechanical checks, open items, decision owners, and reopen triggers.
The useful state chain is:
closed configuration -> prepared configuration -> temporary support engaged -> opening interface released -> segment in its named open state -> passage task completed -> segment returned and seated -> primary lock and any separate retention restored -> temporary support removed only under the authorized condition -> restored mechanical state verified
This is a list of states to define, not a universal opening sequence. The responsible structural, mechanical, installation, site, safety, and acceptance authorities must provide the actual steps, load cases, controls, evidence, and permissions for the project.
This article stays inside mechanical support-frame scope. Cameras, lights, adapters, trays, cables, and other attached items enter only as load, position, centre-of-gravity, envelope, interface, obstruction, and retained or removed-state inputs. Camera or lens selection, capture volume, optical coverage, synchronization, calibration, reconstruction, imaging quality, lighting output, electrical design, controls, and imaging acceptance are excluded. Personnel authorization, training, guarding, lifting procedures, exclusion-zone design, emergency procedures, legal compliance, and risk acceptance also remain outside this guide.
Use StelMount's mechanical engineering scope to frame the physical structure and interface discussion. That page does not prove an opening mechanism, passage clearance, temporary-support design, capacity, stability, relocking result, or suitability for a project.
Define the actual passage task before the opening
A person or equipment route is not described by width and height alone. Give the task a stable ID and record the represented object, its complete envelope, orientation, approach, exit, turns or changes in attitude, carried or attached items, handling aids, support state, and the frame configuration in which movement is expected. If several people or objects can occupy the route, define the project scenario rather than silently combining their dimensions.
For a personnel input, the project authority may need to identify the represented population, clothing or personal equipment as geometric inputs, carried tools or components, posture, approach direction, and whether the person must turn, reach, crouch, or control another object. This guide does not select those inputs or turn them into an entry authorization. ISO 15534-1:2000 is publicly titled around principles for determining dimensions required for whole-body access openings into machinery.[1] Its official subject does not establish that it applies to this frame, supply a person model or dimension, account for clothing or carried items, define safe access, or replace the complete standard and competent project review.
For an equipment input, record the item and revision, rigid and flexible projections, handles, wheels, connectors, cable or hose state, packaging or lifting accessories, required orientation, support or carrier, steering or handling points, and the envelope while moving rather than only at its final position. An item that fits through a static section may still conflict during approach, rotation, elevation change, or exit.
Hsu and Lin studied quantitative component accessibility and product assemblability in a general design-for-assembly setting.[2] Their work supports only the bounded principle that accessibility can be treated as an explicit relationship instead of a visual impression. It provides no person or equipment clearance, tool, route, support, sequence, acceptance criterion, safe-access conclusion, or StelMount result.
Map the approach, the opening, the swept route, and the exit as separate zones. Include the moving frame segment, hinges, rails, guides, handles, locks, temporary supports, adjacent frame members, bases, attached equipment, cables, trays, floor features, walls, doors, and other project-owned obstructions. A clear final opening does not prove that the segment can reach that position or that the object can traverse the full route.
The adjacent StelBooth guide explains why a task, object, approach, removal path, and surrounding state must be named before maintenance clearance can be reviewed. That spray-booth context supplies no frame opening, personnel envelope, equipment route, value, method, temporary support, or acceptance for StelMount.
Name the frame states before choosing an opening mechanism
The same physical structure can have materially different mechanical states. At minimum, decide which of the following are required and give each one a configuration key:
- Closed / operating: the segment is seated, locked, retained as required, and represented by the operating load and base state.
- Prepared: the project-defined attached items, accessories, cables, obstructions, and loads have reached their required pre-opening state.
- Temporary support engaged: the named support interfaces have been established and verified for the transition case.
- Unlocked: specified primary connections or locks are released while the segment remains controlled by the defined support and guide system.
- Moving: the segment travels through its named path with the recorded load, support, base, and obstruction state.
- Fully open / passage: the segment is at its controlled open position and the project-defined route is represented.
- Returning / seated: the segment has returned and the mating interfaces or datum cues have reached their defined relationship.
- Locked / retained: the controlled primary lock and any separately required retention are restored.
- Restored / verified: the named closed configuration has passed the required mechanical checks and received the project disposition.
Do not merge these labels. A segment can be seated but not locked, locked but not checked against its restored geometry, or fully open while the passage task remains unresolved. Likewise, an operating load case does not automatically cover an unlocked, moving, or temporarily supported state.
The public StelMount systems overview provides vocabulary for ARC, RING, DOME, GRID, TUNNEL, MOBILE, and related structural families. It is not a catalogue of fixed opening designs and publishes no M5 segment, mechanism, state, dimension, load, support, sequence, or verification result.
For every state key, list the frame geometry and revision, base/floor condition, attached-item and load revision, adjustment positions, cable/accessory state, opening-segment position, temporary support, permitted mechanical action, evidence status, and owner. If one of those inputs changes the load path or route, create another state instead of overwriting the record.
Define the opening section as a complete interface
Name the Opening Segment ID and show its boundaries on controlled views. State whether the proposed concept is hinged, sliding, rolling, telescoping, lifted, fully removable, split into several parts, or another defined mechanism. These are alternatives to describe, not universally interchangeable solutions.
For a hinged segment, define the hinge line and interfaces, segment path and sweep, end positions, support and restraint states, adjacent interference, seating features, connections, lock, retention, service access, and inspection. For a sliding or rolling segment, define rails or guides, travel path, support at each position, end stops, derailment or release boundary supplied by the design, contact and alignment features, access, and return state. For a removable or lifted section, define separation interfaces, supported state before release, handling and storage interfaces, orientation, reinstallation datum features, and the point at which the restored load path is re-established.
Demoly and coauthors presented an assembly-oriented framework linking product-structure engineering with assembly-sequence planning.[3] That general research supports reviewing the segment, its interfaces, and the transition plan together. It does not prescribe an opening mechanism, sequence, load transfer, temporary support, handling method, hold point, crew, or project acceptance for this frame.
Record every connection crossed by the opening boundary. Include structural joints, fasteners, pins, latches, clamps, hinges, rails, stops, index features, backing or bracing, and mechanical cable or accessory interfaces. Identify which connections carry, locate, guide, lock, retain, or merely identify. The presence of a pin, latch, handle, caster, rail, or stop does not prove its function, independence, capacity, engagement, or suitability.
Treat flexible services and attached accessories as mechanical interface inputs only. State what stays connected, what disconnects, what is supported separately, what can move, what can snag or obstruct, and which authority owns the non-mechanical system. Do not design cable ratings, electrical separation, lighting, controls, data, heat management, synchronization, or optical performance in this article.
Define temporary support and the changed load path
Before any connection is released, the structural and mechanical authorities must define the resulting load path. Record the complete supported-item/load revision for the transition, the segment's own mechanical inputs, the base and floor/support state, the members and interfaces that remain active, and the elements transferred to temporary support.
A temporary support record should identify the supported element, support component or system ID, contact and attachment interfaces, engaged geometry, reaction and load-case source, base/floor or adjacent-structure input, installation and verification evidence, responsible party, permitted frame actions, monitoring or inspection inputs if required by the project, and the exact condition for release. This is an information checklist, not a temporary-works design.
Do not infer a temporary support from a prop drawn under a segment or from a statement that the section is lightweight. The design authority must provide the loads, reactions, stability relationships, support capacity basis, interface details, tolerances, setup method, and acceptance criteria. StelMount or a fabricator can confirm only the scope and evidence expressly agreed for the project.
NASA-STD-5001B with Change 3 provides a deliberately bounded example of configuration-aware evidence discipline in its spaceflight-hardware domain: it discusses defined requirements, representative configurations, documented deviations, and verification by test or analysis.[4] The same standard has express applicability limits and exclusions, including design-load determination and ground support equipment. It supplies no temporary-support load, factor, interface, method, criterion, approval route, or StelMount result. Its limited use here is to keep the checked configuration and any deviation visible.
Define the release condition for temporary support separately from the relocking action. A fastener or latch may be engaged while the restored load path, base state, bracing, geometry, or inspection remains open. Remove or unload the temporary support only when the project-defined prerequisites and authorized evidence state have been reached.
If floor capacity, anchorage, ballast, levelling, caster, foundation, wall connection, overhead support, or adjacent structure influences the transition, route that input to its responsible authority. This article provides no stability calculation, foundation reaction, support spacing, anchorage design, load value, or operating permission.
Write a project-specific transition record, not a generic sequence
Create one row for every action that changes the mechanical state. The row should identify the pre-state, permitted action, prerequisites, actor, resulting state, hold point, observation or record, exception path, and authority that releases the next action.
| Pre-state | Project-defined action | Required inputs before action | Resulting state | Evidence / hold | Owner |
|---|---|---|---|---|---|
| Named closed configuration | Project entry | Current frame/base/load/obstruction record | Named prepared state | Project entry | Named party |
| Named prepared state | Project entry | Temporary-support design and setup inputs | Support engaged | Project entry | Named party |
| Support engaged | Project entry | Connection-release and remaining-load-path inputs | Unlocked or moving | Project entry | Named party |
| Named open state | Project entry | Passage-task and obstruction inputs | Passage complete or return authorized | Project entry | Named party |
| Returned / seated | Project entry | Mating, datum, lock and retention inputs | Locked / retained | Project entry | Named party |
| Locked / retained | Project entry | Restored-state checks and disposition | Restored / verified | Project entry | Named authority |
The rows are blank on purpose. They do not prescribe that every frame uses these exact actions or this order. A hinged segment, sliding panel, lifted ring section, removable rail, split tunnel, or multi-part opening can have different dependencies. The approved project method controls.
Keep personnel safety and work authorization outside the mechanical transition table. The table may point to a separate authorized procedure, lifting plan, exclusion control, or permit record when the project requires one, but it must not summarize that pointer as proof that the work is safe or legally permitted.
Stop when a pre-state cannot be verified, a support or guide is missing, an obstruction differs from the controlled model, an attached item/load revision is unknown, a connection does not reach its expected state, or the resulting configuration has no disposition. Record the exception; do not skip forward to the next label.
Define seating, relocking, retention, and restoration separately
Returning the segment to its closed position is not the same as restoring the frame. Define the mating faces, shoulders, keys, pins, rails, stops, hinge relationships, index features, fastener groups, latches, clamps, and other project-selected interfaces. State which features locate, transfer load, prevent unwanted movement, create the primary lock, provide separately required retention, and furnish an inspection cue.
Write the seating state before the lock state. Seating may require named contact, alignment, gap, insertion, pin position, or datum relationship. If a component can appear closed while not fully engaged, define how the project detects that condition. Do not rely on handle direction, paint marks, sound, visual proximity, or initial tightness unless the controlled design and evidence plan expressly make that cue meaningful.
Where a threaded fastener or clamp forms part of the lock, identify the exact parts, usable engagement, mating and bearing surfaces, finish, clean or lubricated state, reuse rule, installation tool, controlled procedure, access, and inspection evidence. ISO 16047:2005 publicly addresses torque/clamp-force testing for fasteners.[5] Its official subject supplies no universal torque, clamp force, friction value, tightening procedure, lock capacity, cycle life, or StelMount result. The responsible manufacturer and project records must provide those inputs.
If the selected design uses a positive latch, pin, wedge, catch, over-centre mechanism, secondary cable, stop, or another retention feature, define that actual mechanism without borrowing threaded-fastener logic. State its engagement relationship, load path, independent or dependent status, access, inspection cue, release method, replacement boundary, and evidence. A secondary feature is not automatically independent or rated because it is present.
The existing StelMount guide on payload, seating, locking, and retention at one mounted-item interface provides narrower comparison vocabulary. It does not define the opening segment, whole-frame load path, temporary support, restored geometry, or M5 acceptance.
Relocking evidence should represent the actual state after the full transition, not an isolated bench assembly. Record the frame and base configuration, segment and connection revisions, retained items and loads, temporary-support state, installation procedure revision, deviations, inspection results, and authority. If the opening is expected to repeat, the project must separately define any cycle, wear, maintenance, replacement, or re-verification requirements; this article supplies none.
Verify the restored mechanical state
Verification should answer distinct questions rather than produce one generic "closed" status:
- Does the actual passage opening and route represent the approved task state?
- Has the segment returned to the required seating relationship?
- Are primary locks and separately required retention in their defined states?
- Has the intended permanent load path been restored before temporary support is released?
- Does the restored frame meet the project-defined mechanical geometry and structural evidence requirements for the named configuration?
For geometric restoration, identify the characteristic, physical datum features, datum realization, frame/base/support state, attached-item revision, method, instrument or fixture where applicable, environmental conditions, criteria, result, uncertainty or decision-rule source where required, limitation, and disposition owner. ISO 5459:2024 publicly addresses datums and datum systems in geometrical product specifications.[6] The official record does not choose a frame datum, origin, coordinate system, tolerance, fixture, measurement method, restoration rule, optical alignment, or conformity.
The adjacent StelTherm guide explains why shipping splits and reassembly datums must stay tied to the represented assembly state. That exchanger-frame context supplies no StelMount datum, opening interface, tolerance, temporary support, method, or restored result.
For structural or load evidence, name the exact configuration, load-case revision, segment position, base/floor/support state, temporary-support condition, boundary assumptions, method, criteria, deviations, result, date, record and approving authority. NASA's configuration discipline is relevant only as the bounded methodological example already described; it does not authorize a project test or analysis route.[4]
Keep inspection, dimensional measurement, analysis, test, operational check, safety authorization, project acceptance, calibration, and imaging acceptance as separate evidence types. A mechanical restored-state check cannot establish camera coordinates, capture volume, optical coverage, synchronization, calibration, reconstruction, or image quality.
Evidence for one opening segment, load set, base state, temporary support, sequence, lock method, revision, or adjustment position does not silently transfer to another. Record the comparison and authorized basis if evidence is proposed for reuse. Otherwise, mark the new state pending.
Use the Openable Frame Access and Relocking Register
Create one keyed record per Frame Configuration ID, Opening Segment ID, Passage Task ID, and transition revision. If the equipment envelope, attached load set, base state, support, mechanism, sequence, lock or evidence basis changes, create another state or revision rather than overwriting the prior record.
Part A - Task, geometry, interface, and temporary support
| Field | Record for the named configuration | Hold when |
|---|---|---|
| State and scope | Frame Configuration ID, segment and task IDs, drawings/revisions, base state, attached-item/load revision and intended action | The record describes a generic frame or opening |
| Passage envelope | Person/equipment definition, complete moving envelope, carried/attached items, orientation, approach/exit, turns, handling/support state and owner | A nominal gap or final position substitutes for the route |
| Surrounding state | Adjacent members, bases, floor/site inputs, cameras/lights/accessories/cables as mechanical inputs, and retained/removed obstruction state | The controlled view omits a relevant physical item or state |
| Opening interface | Segment boundaries, mechanism/path, guides/supports/stops, connections, seating, locks, retention, access and inspection features | The mechanism is named but its complete interface is not |
| Temporary support | Supported elements, support ID/interfaces, load/reaction source, engaged state, setup evidence, permitted actions, owner and release condition | A connection would be released with an undefined resulting load path |
Part B - Transition, relocking, evidence, and release
| Field | Record for the resulting state | Hold or reopen when |
|---|---|---|
| Transition step | Pre-state, action, prerequisites, actor, resulting state, hold/evidence, exception and next-release authority | The state or owner is implicit, or another configuration's sequence is copied |
| Seating | Mating/location features, datum cues, required relationship, method/result and owner | Appearance of closure substitutes for defined seating |
| Lock and retention | Exact mechanism/parts, controlled procedure, access/tool state, primary lock, separate retention, inspection cues and evidence | Handle/fastener position or initial tightness is treated as complete proof |
| Restored geometry | Characteristic, datum realization, configuration, method, criteria, result, limitation, record and authority | The result cannot be tied to the restored state |
| Structural/mechanical evidence | Load/base/support state, assumptions, analysis/test/inspection type, criteria, deviations, result and approver | Evidence belongs to another state or lacks scope |
| Change and release | Changed input, affected states/interfaces/records, disposition, release owner/date and reopen trigger | A material change has no connected review |
The register is an editorial decision tool. It is not an access standard, frame design, load or stability calculation, temporary-works design, personnel procedure, lifting plan, universal sequence, torque table, inspection interval, test method, product rating, safety conclusion, calibration record, or acceptance certificate.
Read Part A left to right before any opening transition. Then read Part B backward from a restored-state claim: the release should lead to a named evidence record, current relocking state, temporary-support release condition, exact opening segment, complete passage task, attached load revision, base state, and controlled drawings. Keep the transition held when either path breaks.
Useful statuses include "input missing," "passage envelope pending," "temporary-support basis under review," "prepared for named transition," "support engaged for named state," "segment open under controlled state," "returned and seated," "locked/retained - restoration evidence pending," and "restored for the named mechanical configuration by the named authority." Avoid unqualified labels such as quick-open, safe, stable, rated, tested, verified, repeatable, or accepted.
Assign owners, control change, and issue the RFQ
The customer or system/design authority defines the passage task, supported items, permitted configurations, site interfaces, evidence needs, and project acceptance. The structural/mechanical authority defines load cases, open/closed/transition load paths, temporary support, segment/interface design, relocking basis, restoration criteria, and verification. StelMount or the fabricator confirms only the manufacturability, supplied components, inspections, and records accepted in written scope.
The installation party performs only the assigned transition and records its actual state. The site/floor/support authority supplies receiving geometry and support conditions. The safety/compliance authority owns personnel authorization, methods, controls, applicable law, and risk acceptance. One organization may hold several roles, but the states and evidence remain separate.
Reopen affected records after any change to the passage object, carried or supported item, load/position revision, frame geometry, segment, hinge/slide/remove mechanism, interface, base or floor state, temporary support, cable/accessory obstruction, transition step, fastener/latch/pin/retention, datum, method, criteria, drawing revision, or responsibility. Reopen means controlled impact review, not automatic rejection of unaffected scope.
Send the completed register, current frame and site views, person/equipment envelope definition, attached-item/load schedule, opening-interface details, temporary-support basis, transition record, relocking instructions, mechanical verification plan, evidence index, open-item owners, and revision register through the StelMount configuration inquiry. The page collects project inputs; it does not submit this local article or prove a configuration.
Final stop line
An openable frame is not ready because a segment can move or a nominal object appears to fit. It is ready for the named transition only when the project can trace the complete passage task, current frame/base/load state, opening interface, temporary support, state steps, seating, relocking, restoration evidence, limitations, and authorized owner.
If any connection would be released before the resulting load path and support state are defined, stop. If the closed-state release cannot be traced backward through current evidence to the exact restored configuration, keep that state held. Complete the Openable Frame Access and Relocking Register before opening or reuse.
References
- International Organization for Standardization, ISO 15534-1:2000, Ergonomic design for the safety of machinery - Part 1: Principles for determining the dimensions required for openings for whole-body access into machinery. Official ISO record. Public title and subject only; no applicability, person input, dimension, safe access, procedure, compliance or StelMount result is supplied. Back to citation
- H.-Y. Hsu and G. C. I. Lin, "Quantitative Measurement of Component Accessibility and Product Assemblability for Design for Assembly Application," Robotics and Computer-Integrated Manufacturing, 18(1), 13-27, 2002. DOI. General DFA accessibility context only; no person/equipment clearance, route, method, safe-access conclusion, acceptance or frame result transfers. Back to citation
- F. Demoly, X.-T. Yan, B. Eynard, L. Rivest and S. Gomes, "An Assembly Oriented Design Framework for Product Structure Engineering and Assembly Sequence Planning," Robotics and Computer-Integrated Manufacturing, 27(1), 33-46, 2011. DOI. General assembly-planning context only; no opening mechanism, sequence, temporary support, load path, hold point or project result transfers. Back to citation
- National Aeronautics and Space Administration, NASA-STD-5001B with Change 3: Structural Design and Test Factors of Safety for Spaceflight Hardware, 2022. Official NASA record. NASA spaceflight scope only, with explicit applicability limits and exclusions; no project load, factor, temporary support, test method, criterion, approval route, certification or StelMount result transfers. Back to citation, occurrence 1 Back to citation, occurrence 2
- International Organization for Standardization, ISO 16047:2005, Fasteners - Torque/clamp force testing. Official ISO record. Public subject only; no torque, clamp force, friction state, fastener, procedure, lock capacity, cycle life or StelMount result is supplied. Back to citation
- International Organization for Standardization, ISO 5459:2024, Geometrical product specifications (GPS) - Geometrical tolerancing - Datums and datum systems. Official ISO record. Public title and subject only; no frame datum, coordinate system, tolerance, method, restoration rule, optical alignment, applicability or conformity is supplied. Back to citation