IEEE Consumer Electronics Magazine - May 2018 - 83

The Recon Snow2 [16] is a commercially available headmounted display similar in design to that in Google Glass,
though specifically developed for alpine/winter sports. The
Recon Snow2 offers a variety of features to help skiers track
their performance, including the current speed, altitude difference, and distance covered. It also supports real-time
friend tracking via onboard ski resort maps and an accompanying mobile app. The interaction with the head-mounted
display is performed via a glove-compatible controller on
top of a ski jacket's wrist, featuring a remote controller that
has six stand-out buttons that can be easily pressed through a
ski glove.
The RideOn [17] also started as a crowdfunding campaign
and claims to be the first-ever augmented reality (AR) ski
goggles that project real-time information onto a set of
virtual layers at a distance of 5 m in front of the wearer. RideOn is based on the Android operating system, provides connectivity with mobile devices, and is expected to arrive on the
market shortly.

s-HELMET: A SMART SKI HELMET
FOR INCREASING ON-SLOPE SAFETY
Ski helmets have become a necessity for almost everyone on
the slope, with some ski resorts establishing mandatory ski
helmet use for children below the age of 16. Despite the constantly increasing adoption of helmets, part of which owes to
more ergonomic and appealing designs, skiers who still
refrain from using one often report interference with hearing
as a reason for doing so. In fact, a study by Ruedl et al. found
that wearing a helmet significantly reduces one's ability to
accurately localize a sound source [4]. This means that a helmet wearer is less aware of his or her surroundings and
potentially other skiers approaching from the back. If we also
take into account habits such as listening to music via earplugs while skiing, this effect is further exacerbated and
could potentially lead to an increase in on-slope accidents.

sensitive. A quick back-of-the-envelope calculation shows
that at a relative speed of 10-20 km/h (2.5-5.5 m/s) between
two skiers offers about 1-2 s of warning.
The microcontroller board processes the LIDAR data
inputs and notifies the wearer of the direction of skiers
approaching from the back using three corresponding LEDs
(left, center, and right). The LEDs are placed on the front of
the helmet within the wearer's peripheral field of view to
indicate from which side a skier might be approaching.

AIM AND APPROACH
The s-Helmet [6], [18] (see Figure 1) aims to augment a skier's peripheral perception of nearby skiers and their movement on the slope. It specifically focuses on traverse slopes-
narrow slopes, often with minimal incline, that connect different ski areas or ski resorts. While the slight incline seems
to imply less danger than on an actual slope, the lack of a
grade, coupled with the long distance covered on such a slope,
often means that skiers must enter such traverse slopes at high
speed to cross them fully without the need for skating or, in
the case of snowboarders, walking. These high speeds, combined with the often-narrow character of traverse slopes, make
them significantly more dangerous than they seem.
Note that relative speeds between skiers during these
encounters need not be high. At high velocities, simple movements by a skier in front can quickly cut off the path of an
approaching skier, who may not have the time or the skill to
avoid a run-in or a fall. This relatively constrained setting
offers the opportunity to significantly increase a skier's awareness without the cost of greater cognitive load. Similar to a
vehicle's side mirrors on a highway, a set of simple peripheral

PROTOTYPE
We created the s-Helmet following a participatory and iterative design process for extracting the basic requirements,
incorporating feedback from actual skiers and snowboarders.
Based on the elicited specifications, we produced the design
shown in Figure 1. The s-Helmet prototype comprises three
LIDAR sensors, a microcontroller development board (Teensy 3.0), three LEDs, and two light lithium-ion polymer batteries (2,000 mAh each), all mounted on a regular ski helmet
(size 60-62 cm).
The LIDAR sensors measure the distance of approaching
skiers by detecting and analyzing the reflected laser beams
emitted from the back of the helmet. LIDARs are extensively
used in the automotive domain, primarily for collision avoidance
and detection of large objects (e.g., other vehicles and pedestrians) [5]. While the LIDARs are able to detect approaching
skiers up to 30 m away, we purposely limited their detection
range to 5 m, as this distance seemed to strike a reasonable
balance between offering sufficient warning and not being too

(b)

(a)

(c)

FIGURE 1. (a) A participant wearing an s-Helmet prototype during the off-slope experiment. The (b) front view and (c) rear view
of the s-Helmet.

MAy 2018

IEEE Consumer Electronics Magazine

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