Tactile pavements are guiding phone users

Case

Tactile pavements are guiding phone users

Researchers Sjoerd Bruijn and Myrthe Plaisier have discovered that corduroy paving for the blind and visually-impaired can also be useful for people with normal vision. Such paving makes it easier to walk in a straight line.

Bruijn conducts research into gait stability and Plaisier studies tactile perception. Both started their research projects in 2013 with a Veni grant. Bruijn and Plaisier (both aged 33) are affiliated to the Faculty of Behavioural and Movement Sciences at VU University Amsterdam, where they in fact ‘bumped into’ one another quite by accident. One thing led to another, and an ad hoc research project into ‘feeling with your feet’ on corduroy paving and the effect on gait stability was born.

Two Bachelor’s students – Nanda Pluijter and Lieke de Wit – gathered data from ten 'study participants' who carried out walking exercises on tram and bus platforms near the university. Highly detailed data on the participant’s movements was saved in a mobile phone attached to the participant’s back during these exercises. This was done using an app that stored data such as acceleration and orientation with respect to gravity from the sensors in the phone. Every step taken was therefore monitored, allowing the team to study the exact effect of the pavement surface in different situations. The respondents were either given safety glasses with mat glass or glasses through which they could see nothing at all, to simulate the situation for a blind or visually-impaired person.

What happens in the brain? That's what we want to know precisely
- Sjoerd Bruijn and Myrthe Plaisier

The result? If you are a pedestrian with normal vision, the corduroy paving aids your sense of direction as the tactile information you receive through the soles of your shoes supports your internal compass. Myrthe Plaisier: ‘Using a mobile phone while you are walking causes accidents. It is no wonder really, because if you are using WhatsApp or looking for music on Spotify, you cannot see where you are walking. Anyone who wanders around with no sensory information (eyes and ears shut) will eventually walk in a circle, with the result that you bump into something or somebody.’

However, it is possible to feel where you are walking, and this is where tactile paving – used on station platforms and in other public spaces for a completely different purpose – can help. It is certainly no luxury, because a considerable increase can be seen in the number of accidents caused by pedestrians using phones... remarkably more than those caused by drivers using phones or cyclists on WhatsApp. If corduroy pavements can help prevent accidents, the idea is worth developing further.

Photo Myrthe PlaisierMyrthe Plaisier

Corduroy paving is already a common feature at railway stations and at bus and tram stops. It helps the blind and visually impaired move around safely on platforms and in large, open spaces. ‘However, there is a disadvantage to walking on corduroy pavements,’ says Sjoerd Bruijn, ‘which is that it can cause people to walk more unsteadily. The sense of direction increases, but stability decreases, which means there is more chance of a fall. After all, our normal way of walking straight ahead, following our nose, is fairly stable – but to the side, following our ears, is not. The ridges intensify the sense of listing, as if you are going to twist your ankle.’

Both researchers have come up with recommendations for different patterns on the corduroy pavement slabs. Slabs are needed not just with straight ridges and grooves, but V shapes that also act as arrows to show the direction of travel. The hope is that gait stability will then not be affected, but the best pattern to be used is the subject of further research.

Opening a lock with gloves on

Did you know? Up to three marbles or sweets in your hand without looking requires no counting. Anything more and it becomes difficult.

Myrthe Plaisier conducts research into the sense of touch in her Veni project ‘From grouping to haptic object perception’. ‘All points of contact between an object and the skin must be connected correctly to be able to perceive an object. However, how does the human brain solve this complex puzzle? This is what my research is about. Think of everyday activities such as counting a number of objects in your hand, without looking. Up to three – marbles or sweets, for example – requires no counting, but more and it becomes difficult. The question is: why is that? The tactile information that reaches your brain through your hands holds some fascinating secrets – just try opening a lock with gloves on.’

Photo Sjoerd BruijnSjoerd Bruijn

As part of his Veni project ‘The walking brain; how our brain stabilizes our unstable locomotion’, Sjoerd Bruijn mapped brain activity during walking, to try to find out more about how the brains of people who walk with a stable or unstable gait control the activity. ‘For example, we studied people in stabilising situations (who were ‘tied’ down using elastic) and destabilising situations (who had to walk on a kind of ‘cakewalk’). What happens in the brain? That is the question I hope to answer.’

Using the combined knowledge of Bruijn and Plaisier, ‘the world outside’ could become a safer place. After all, it is unlikely that mobile phones are going to stop being used outdoors in the foreseeable future.

The research results were recently published in the international research journal Gait & Posture.