Motorised assistive chair: how to assess movement smoothness, noise and stopping

Operating one movement at a time is the clearest way to assess a motorised assistive chair. The number of actuators tells you how many functions can be separated, but on its own it does not reveal whether start-up, stopping, noise and travel path feel smooth and predictable.

Trying the chair with the actual user makes visible things that an empty demonstration does not show. Weight, posture, hand position and the ability to release the button all change the experience, and they must be taken into account without exceeding the product’s load capacity or instructions.

Assessing Sollevita means distinguishing between the sit-to-stand lift, vertical elevation, recline, leg rest and tilt-in-space, observing each one separately before combining them into a routine.

In brief

• More motors does not automatically mean more quality: what counts is that each axis responds in a controllable and consistent way.
• The movement must stop when the control is released and resume without a perceptible jump.
• Steady noise from the motor and linkages should be distinguished from thuds, squeaks or new changes compared with the normal baseline sound.
• The trial should include returning to the neutral position and the person’s ability to understand which button to use.
• A burning smell, damaged cables or uncommanded movements call for stopping use and contacting support.

Before the trial: preparing the person, the room and the control

Clearing the space in front of, behind and beneath the chair prevents a rug or an object from being mistaken for a fault in the movement. Cables, clothing, animals and other people must stay out of the mechanical area.

Positioning the person fully back makes the trial repeatable. Feet, hands and head must be supported in a way that matches the function about to be operated.

Showing the button before pressing it reduces surprise and lets you check whether the handset is easy to understand. The person needs to know how to stop the movement, not just how to start it.

Recording the room in silence for a few seconds creates a baseline sound. A television, a vacuum cleaner and conversations make it hard to compare normal noise with abnormal noise.

Ten checks for each axis

Starting each function from the neutral position lets you observe the very first instant. The movement should begin predictably, without a jolt that startles the person or suddenly shifts the supports.

Releasing the button halfway through the travel checks the mid-travel stop. The chair must hold the expected position without carrying on moving unexpectedly.

Reversing the direction after a short pause shows whether the response stays controllable. The check should not be turned into a rapid back-and-forth sequence that needlessly stresses components and user alike.

Repeating the check with the person seated lets you assess the feel and stability, always in line with the instructions. An empty run remains useful for the technician, but it does not replace the in-use trial.

Smoothness: what it means without vague words

Watching the speed is not enough to define a smooth movement. Smoothness takes in the start-up, the continuity of the travel path, the stop and the absence of sudden changes that do not match the command.

Feeling a change in speed can be normal in certain geometries or near the travel limits. The judgement must rest on the product documentation and on comparison with a correctly working demonstration, not on a universal rule.

Assessing predictability is particularly important for people with stiffness, fear of movement or reduced postural control. The control must leave time to communicate and stop when the person asks for a pause.

Comparing the same function on different days can reveal a change. An initial recording becomes useful as a first-party reference if it is made in the same configuration and without editing.

Normal noise and noise to report

Listening to an electric motor in a quiet room always produces a baseline sound. Fans, gearboxes, actuators and linkages can generate a steady noise that does not automatically indicate a fault.

Recognising a new noise is more useful than looking for a universal decibel threshold. Squeaking, a metallic thud, an intermittent knock or a sound linked to an abnormal stop should be recorded and described.

Locating the sound calls for a side shot and a front shot without putting your hands near the mechanisms. The technician may ask you to operate a single axis to distinguish the backrest, leg rest, sit-to-stand lift or vertical elevation.

Stopping use is necessary if there is a burning smell, smoke, abnormal heat, damaged cables or unwanted movements. Carrying on with the trial to get a better video is not a prudent choice.

Mid-travel stop and the person’s control

Releasing the button must halt the action in line with the behaviour the system is designed for. This lets the person find an intermediate position instead of being forced to always reach the end of travel.

Using small steps helps those with weak hands or a fear of a large movement. The handset must remain within reach even when reclined and must not slip behind the chair.

Communicating before each movement remains essential when the control is handled by the caregiver. The person must be able to ask for a stop and understand which part of the body will change position.

Trying the return to the seated position is more important than reaching the most spectacular posture. A comfortable configuration loses its value if the person or the carer cannot get back with a clear sequence.

The difference between the movements to test

Trying the sit-to-stand lift means observing the path of the pelvis upwards and forwards. Feet, armrests and the space in front must be ready before starting.

Trying the vertical elevation means changing the height of the whole structure with the person seated or lying back. The platform must rise and lower consistently, without being confused with the lift function.

Trying the recline means altering the angle of the backrest relative to the seat. The Push Head can be adjusted after choosing the main inclination.

Trying the tilt-in-space means rotating the seat and backrest together relative to the floor. Zero Gravity is a final configuration achieved by combining several axes and should only be tested once you understand the individual movements.

Trying the leg rest means checking the support for the calves and heels, the space in front and the ease of return. No axis should be judged solely by the length of its travel.

First-party case: one continuous video is more credible than five clips

Recording a single side shot with the control in view makes it impossible to hide idle time, noises or changes of position between one movement and the next. The chair starts from the same neutral configuration for each check.

Overlaying the name of the axis on the video helps the audience distinguish the functions. The labels should describe, not turn into claims like “absolute silence” or “perfect movement”.

Keeping an uncompressed audio track lets the service compare a future noise. The recording should note the room, the phone’s distance and whether the person is present or not.

Publishing the video with a downloadable checklist offers a useful, reusable element: the reader can repeat the check and put precise questions during the consultation.

When to stop the trial and contact support

• The movement carries on after the button is released or starts without a command.
• A burning smell, smoke, a damaged cable or abnormal heat appears.
• The structure strikes an obstacle, tilts unexpectedly or produces a new thud.
• An axis jams with the person in a position they cannot tolerate.
• The handset is wet, broken or has stuck buttons.
• The second check behaves markedly differently from the first with no obvious explanation.

Next step

Ask for a continuous, unedited demonstration of all the axes, with start-up, mid-travel stop, reversal and return to the seated position.

Bring the person who will actually use the control and fill in the ten-check checklist: the Sollevita team can then focus on control and predictability, rather than on a simple count of the motors.

Essential references

• Regulation (EU) 2017/745, general safety and performance requirements for medical devices.
• Instruction manual and safe-use warnings for the Sollevita configuration.
• La Castellana, internal videos and test sheets for the independent movements.
• HSE, Equipment safety in health and social care: use, training, checks and management of faults.