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Robovations
Robovations™
Robot Autonomy, Classified
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Comparison · 2 robots

HOBOT-S6 Pro · Kärcher RCW 4

All robot window cleaners. Every measure below is plotted against the full class, so a difference can be read against how much the class itself varies.

  1. HOBOT-S6 Pro
  2. Kärcher RCW 4

Up to three

01 Classification

What each one does on its own.

The Autonomy Ladder is the same five rungs for every robot on the site. A rung describes the conditions a robot handles without you, not how good it is.

V
Generalized
Any task, any setting
IV
Environmental
Handles new obstacles without help
III
Conditional
Finishes familiar jobs on its own
II
Assisted
Runs preset routines, needs rescue
HOBOT-S6 ProKärcher RCW 4
I
Manual
One action, on command
02 Assessment

Where they actually differ.

The Robovations Score is nine inputs across three pillars, each weighted as shown and each scored so that more is better. A robot can lead on one and trail on another, which is the point of showing them apart. Cost of ownership and data handling are reported on each robot's own page and are never averaged into the score.

Capability

Task completion16% of score
Does it finish the job it is sold to do, unattended
  • HOBOT-S6 Pro75
18median 72 across 433 scored robots100

Not scored: Kärcher RCW 4

Coverage and navigation10% of score
Does it work the whole area, and hold that between runs
  • HOBOT-S6 Pro75
0median 70 across 421 scored robots100

Not scored: Kärcher RCW 4

Edge-case recovery10% of score
Does it recover from the failures its category presents
  • HOBOT-S6 Pro50
18median 52 across 320 scored robots100

Not scored: Kärcher RCW 4

Operating envelope4% of score
How far conditions can vary before performance drops
  • HOBOT-S6 Pro75
28median 68 across 397 scored robots100

Not scored: Kärcher RCW 4

Dependability

Field failure rate16% of score
Documented hardware failures per owner-year
  • HOBOT-S6 Pro73
6median 70 across 359 scored robots100

Not scored: Kärcher RCW 4

Software stability14% of score
Whether updates fix more than they break
  • HOBOT-S6 Pro71
15median 65 across 342 scored robots100

Not scored: Kärcher RCW 4

Support longevity10% of score
Committed parts, service and updates, with dates
  • HOBOT-S6 Pro67
0median 62 across 429 scored robots100

Not scored: Kärcher RCW 4

Ownership burden

Routine maintenance12% of score
Hands-on time it asks for in normal operation
  • HOBOT-S6 Pro32
22median 67 across 434 scored robots100

Not scored: Kärcher RCW 4

Consumables8% of score
Parts that must be bought to keep it working
  • HOBOT-S6 Pro77
8median 69 across 434 scored robots100

Not scored: Kärcher RCW 4

03 Measured against the class

How far apart is a long way?

A number only means something next to the spread it sits in. Each track below is the real range across every classified robot in the class, with the median marked.

Weight22 with a published figure
  • HOBOT-S6 Pro3.6 lbs
  • Kärcher RCW 43.3 lbs
1.3 lbsmedian 3.1 lbs4.8 lbs
Height24 with a published figure
  • HOBOT-S6 Pro3.9 in
  • Kärcher RCW 42.8 in
2.2 inmedian 3.2 in9.4 in

Not compared, because fewer than two of these robots carry a published figure: Price, Suction, Runtime, Charge time, Noise.

04 Ownership

What the numbers leave out.

The trade-off

What each design gives up to be good at what it is good at.

HOBOT-S6 Pro

Manual launch and repositioning. The robot does not autonomously navigate between windows or edges; a user must place it, start it, and move it to the next pane, it is not a set-and-forget window cleaner.

Cord management. The 5 meter power cord caps the working radius from a socket, and its secured DC connector is built to stay joined rather than be extended. Placement has to account for that cord and, separately, for the safety rope, without either fouling the other.

Kärcher RCW 4

Four automatic modes and a 150 mL tank change how long a single pass takes, not whether the unit still has to be carried, plugged in, and started on every pane.

The tank now covers about 100 square meters per fill, but that headroom does not change the underlying mains dependency: every session still starts by finding an outlet within reach of the 5-meter cord.

Thin evidence base: a launch-week record with no independent reviews or owner reports to check Kärcher’s own cleaning-speed and coverage figures against.

Who each one is wrong for

Stated by the record itself. A robot being wrong for a household is a fact about fit, not a fault.

HOBOT-S6 Pro
Fully autonomous outdoor window cleaning
HOBOT-S6 Pro requires manual launch and manual repositioning between panes. It does not autonomously navigate or select windows to clean.
Homeowners with small tight window frames or muntins
Dual mops and head width are optimized for larger panes. Narrow muntins and divided-light windows may require manual cleaning or repositioning to avoid frame contact.
Users needing coverage far from a socket
The power cord is 5 meters, about 16 feet, on a secured DC connector designed not to pull apart in use. That is the working radius from a socket, and there is no cordless variant of this model.
Kärcher RCW 4
Windows with no nearby power outlet
The RCW 4 has no cordless or battery-only mode; a window beyond the 5-meter power cord's reach from an outlet cannot run a cleaning cycle.
High-rise panes beyond the cord's documented reach
Kärcher documents no separate safety-tether or anchor system for this model, so a true high-rise installation falls outside the reach the 5-meter power cord provides.
Leaded, heavily textured, or decorative glass
Continuous suction contact from the cleaning pad assumes smooth flat glass; Kärcher's documented mechanism is not built for leaded or heavily textured panes.
Panes smaller than the documented minimum size
Kärcher specifies a 40 x 40 cm minimum working pane size; smaller windows fall outside the unit's documented operating range and are not a supported use case.
Buyers wanting proven reliability before purchasing
No independent reviews, owner reports, or field failure record exist yet for a product that only debuted at IFA 2026; that evidence gap is real.

What stays your job

The upkeep ownership hands back to you, whatever the autonomy level says.

HOBOT-S6 Pro
  • After every use: Rinse dual mop pads; inspect suction gasket for mineral deposits or debris.
  • Weekly: Soak mop pads in vinegar solution if hard-water spotting is visible; clean edge sensors.
  • Monthly: Replace or deep-clean suction gasket; check cord for insulation damage or kinks.
  • Every 3–6 months: Replace mop pads (~$25–$35 per pair); verify safety rope for frays.
  • Annually: Inspect vacuum motor performance; if suction noticeably reduced, contact HOBOT support for service options.
Kärcher RCW 4
  • After every use: Wipe down the cleaning pad and clear any trapped debris before storage.
  • As needed: Refill the 150 mL detergent tank, checked against its fill-level indicator.
  • Monthly: Inspect the 5-meter power cord and plug for fraying or damage.
  • Monthly: Check the six pump-driven nozzles for mineral buildup or clogging.
  • Every 3-6 months: Replace the cleaning pad once wiping leaves streaks or residue.
  • As needed: Wipe the suction seal and glass-contact edge to maintain an even hold.
05 Evidence

How much each of these is standing on.

Classifications rest on different depths of evidence. A pre-release assessment and a verified one are not the same kind of claim.

Evidence behind each classification
Robot Evidence status Sources reviewed Last assessed
HOBOT-S6 Pro Pending 1 Aug 2026
Kärcher RCW 4 Pending 1 Sep 2026

Robovations classifies robots; it does not rank them. Nothing on this page is a recommendation, and no manufacturer influences a classification or its placement here.