CRAWLER · TETHERED UAV · COLLISION-TOLERANT AERIAL

Three platforms. Do not pretend there is one answer.

Confined-network inspection has long run crawlers, tethered UAVs and collision-tolerant flyers side by side. PipeGuardian chooses the third as its main in-pipe reconnaissance path, and treats the first two as industry baselines that must still cooperate. This comparison is teaching material, not a competitor takedown.

Procurement often fails by scoring every scene on one metric. In a long wet straight pipe a crawler is usually steadier. In a tank that needs long power, a tether is more honest. In obstacle space, shaft transitions and wall-contact viewing, a collision-tolerant flyer starts to make sense. Reviews and vendor manuals keep repeating this. Sales copy sometimes forgets.

Named vendors, universities and public programmes on this page are contrast questions: what must our own rig answer, and what must public copy forbid. Copying an external figure into a PipeGuardian spec sheet conflicts with the evidence page. Target numbers live on the specs page, all labelled unverified. When not to fly is also a safety decision.

CCTV crawler

Mature municipal drain inspection flow, standard reports and operator ecology;
Long straight pipe, wet, tethered power — good for continuous push;
Shaft transitions, steps, local collapse and complex 3D space cost more to deploy;
Small-diameter crawlers (for example Deep Trekker) show that a flyer is not an answer for every diameter. That is industry contrast, not a PipeGuardian field result.

Tethered confined-space UAV

Products such as ScoutDI bind power, data and recovery to a cable — tanks, sewers, tunnels, long looks;
The audit path is clear: the kit is still attached, so in principle it can be found;
Drag, snag, bends and depth are physical limits;
PipeGuardian treats tether / wire as a weak-link backup, not the only form. ScoutDI is architecture contrast, not a field score.

Collision-tolerant aerial

Elios-class and domestic spherical / ducted cages show contact, roll recovery and obstacle space;
Endurance, dust, gas, explosion protection and the data workflow still have to be taken seriously;
Manuals often say not for explosive / flammable atmospheres — that honesty is the lesson, not a footnote to skip;
PipeGuardian target specs are all unverified. See the specs page. Flyability-class bound-writing is a classroom, not a certificate we hold.

DECISION GUIDE

When not to choose a flyer

A useful systems company writes when not to use itself. That cuts bad trials and protects the field.

Prefer a crawler

Known long straight drain, a standard CCTV report is required, wet medium with a mature procedure, diameter below the flight envelope.

Prefer a tethered UAV

Tens of minutes of continuous look, radio almost unusable, recovery must be physically guaranteed, relatively open space such as a tank.

Prefer collision-tolerant flight

Obstacles, shaft transitions, wall-contact viewing, crawler deployment is hard, and the scene is dry, de-energised, non-explosive and recoverable.

None should enter

Unassessed explosive atmosphere, no recovery, a statutory rescue duty wrongly shifted, no supervisor and no gas monitoring. Reading this page is not a confined-space permit.

Public EMSD confined-space robot and PipeScan AI explorations show that local utilities care about defect recognition and fewer people going in — not a flying show. Pipeline-robot research such as work associated with Peking University Nanchang reminds that gas and drainage have different institutional constraints. PipeGuardian treats those public sources as industry lessons. They are not written as our own bid wins.

English method pages sit next to this comparison: system architecture, technology, safety bounds, target specifications and the confined-space industry map. Field application exists. Concept, laboratory and field stay distinct. This page is not a production photograph.

Citation discipline: Named vendors, universities and public programmes on this page are industry contrast. They are not PipeGuardian test results, customer relationships or awarded funding. Target specifications stay unverified until a matching evidence gate closes.