A robotic floor scrubber has one job: leave a large indoor floor clean and dry, repeatedly, without a human on board. Two linear actuators make that possible — one that lifts the scrub deck, and one that lifts the squeegee. Get them right and your robot cleans reliably for years; get them wrong and you generate service calls, streaky floors and warranty claims. This guide walks through how an autonomous scrubber works, the two critical actuator functions, and how to size and protect them.

Part of our cleaning-robot actuator series. For the full picture, start with the pillar guide: Linear Actuators for Autonomous  Cleaning Robots.

How an Autonomous Floor Scrubber Works

The Scrub Deck and Cleaning Cycle

The scrub deck holds the floor-engaging brushes (disk or cylindrical) and presses them onto the floor while dispensing cleaning solution. The deck must apply consistent down-pressure during cleaning, then lift clear when the robot crosses a threshold, turns in a tight aisle, or finishes a zone. That raising and lowering is performed by the deck lift actuator — a component called out directly in commercial scrubber service documentation such as the Nilfisk SC6000 and Flex3 manuals.

The Squeegee and Solution Recovery

Behind the deck, a rubber squeegee blade wipes up the dirty solution so the floor is left dry and safe to walk on. The scrub-deck skirts control the solution on the floor so the squeegee can pick it up (Flex3 service manual). For this to work the squeegee must sit at the correct height and tilt — and it must lift out of the way at the right moments, which is the second actuator's role.

The Two Critical Actuator Functions

Brush Deck Lift Actuator

The deck lift actuator sets cleaning down-force and clears obstacles. On many machines a single-touch control commands the lift — the Flex3 manual notes that "the one touch switch controls the motors and lift actuator." For an autonomous robot, this manual control is replaced by the robot's controller, but the mechanism and load are the same. Key design points:

• Size for dynamic deck load, including the brushes and any down-force spring preload.
• Provide enough stroke to clear the highest threshold the robot must cross.
• Use position feedback so the controller knows deck state (up/down) reliably.

Squeegee Lift Actuator

The squeegee lift actuator raises and lowers the recovery blade. Its single most important behavior is automatic lift in reverse: when a scrubber backs up with the squeegee down, the blade can fold under and wear or tear, so the control logic lifts it (Tennant / Nilfisk service manuals). For an autonomous robot that constantly maneuvers and reverses in tight spaces, reliable squeegee actuation is essential to recovery performance and blade life.

Force, Stroke and Speed Requirements

Sizing the Deck Lift Load

The deck is the heavier of the two loads. Account for brush assembly weight, any spring preload that creates cleaning pressure, and shock when the deck drops. Actuators offered for sweepers and scrubbers commonly span a wide force band — into the multi-thousand-newton range for deck and heavy functions (TiMOTION sweepers/scrubbers application page) — so match the actuator to your specific deck rather than over- or under-spec'ing.

Why Squeegee Auto-Lift Matters in Reverse

The squeegee load is lighter, but the duty is demanding: it actuates on every direction change. Prioritize a high duty cycle and consistent, repeatable stroke over raw force here. A worn or sticky squeegee actuator shows up immediately as water left on the floor.

For a detailed teardown of both mechanisms — including height/tilt adjustment and mounting — see Squeegee Lift, Brush Deck & Side-Brush Actuator Mechanisms Explained.

Protection Against Water, Detergent and Debris

Why Indoor Scrubbers Still Need IP66+

It is tempting to under-protect an indoor machine, but a scrubber deliberately puts water and detergent on the floor — exactly where the deck and squeegee actuators live. Detergent is also mildly corrosive. IP66 is a sensible baseline; machines that get high-pressure washdown during maintenance, or that double as indoor/outdoor units, justify IP69K, which leading suppliers promote specifically for this application (TiMOTION sweepers/scrubbers application page). We compare the two in depth in IP66 vs IP69K Actuators for Cleaning Robots.

Acoustic and Duty-Cycle Considerations for Indoor Use

Robotic scrubbers increasingly work in occupied spaces — retail, healthcare, light industry. Gausium positions its Mira scrubber for exactly these agility- and environment-sensitive settings (Gausium). Two implications for actuator choice:

Noise: specify low-noise actuation; a loud lift cycle is noticeable in a quiet store or ward.

Duty cycle: indoor robots make frequent short trips with many deck/squeegee cycles per hour, so verify the actuator's rated duty cycle against your busiest mission profile.

JDR Actuator Options for Floor Scrubbers

For robotic scrubber builders, Wuxi JDR Automation (jederoo.com) offers:

• 12V/24V DC actuators matched to mobile-robot battery buses.
• IP66 industrial protection as a baseline, with higher protection engineered on request for washdown duty.
• Hall-effect position feedback for reliable up/down sensing and synchronization.
• CE and UL certified lines for North America and Europe.
• OEM customization of force, stroke and mounting, with 24-hour sample quotes.

(Source: jederoo.com product pages and FAQ.)

FAQ

How many actuators does a robotic scrubber need?

At least two for core function — deck lift and squeegee lift. Machines with actuated side brushes add more.

What fails first on a poorly specified scrubber actuator?

Usually the squeegee actuator, because it cycles on every reversal, or any actuator whose IP rating is too low for detergent exposure.

Can I drive both actuators from one controller?

Yes — with Hall-effect feedback and a suitable controller you can sequence and synchronize them (jederoo.com FAQ).

Get Engineering Support

📐Request a custom deck/squeegee actuator drawing (CAD/STEP)⚡Get a 24-hour sample quote📊Download the floor-scrubber actuator selection sheet

Related: Pillar guide · Mechanism teardown · IP66 vs IP69K