SANDBOX VR

LIMBS TRACKER

A modular wearable system for VR limb trackers that simplifies gear-up while delivering a secure fit, stable tracker positioning, and consistent tracking performance throughout active gameplay.

Problem

VR limb trackers can be difficult to use because they often require time for setup, may experience orientation errors that affect tracking accuracy, need proper fitting to stay secure and comfortable under high impact gameplay, and require regular cleaning to maintain hygiene and performance.

Time: long setup, adjustment, and removal times. Orientation: left/right and front/back confusion affects tracking accuracy.

Size: must fit all wrist and hand breadth sizes from six-year-olds to adults, and all types of garment. Clean: sweat and dirt accumulate, hard to wipe, and cleaning degrades the material.

Various types of securing mechanisms were explored throughout the design process. Each concept was evaluated for ease of use, security, comfort, durability, and its ability to maintain consistent tracker positioning during active VR gameplay.

Woven velcro straps: flexible and elastic, but absorb sweat and gradually lose fastening performance with prolonged use.

Watch straps: familiar for most users, but their limited one-size-fits-all length leaves a long excess strap for users with smaller wrists or ankles.

Magnetic silicone straps: secure and reliable fit, sweat and water resistant, and easy to clean.

Concept sketch sheets exploring strap and tracker forms

Modularity

The same wrist/ankle straps accommodate both left- and right-side variants :
Left wrist (L) / Left ankle (L) / Right wrist (R) / Right ankle (R)

Single wrist and ankle strap designs are used throughout, mounting in opposite orientations, onto the same tracker base. This mirrored installation enables full left/right compatibility with single strap designs, which also minimises production and storage costs.

Adjustment

The wide adjustment range accommodates a variety of wrist sizes, making the strap suitable for both children and adults. This adaptable design provides a personalized fit without the need for multiple strap sizes.

Anthropometry reference table: hand breadth, wrist circumference, ankle height, and ankle circumference for children, female, and male populations

Wrist and ankle fit tested across small, medium, and large sizes, and over skin, socks, joggers, pants, jeans, and boots

Magnets arrangement

Most magnetic watch straps currently on the market can only be used in a specific orientation, users cannot secure the strap end if it is too long.

To address this limitation, magnets with alternating polarity are integrated into the strap, enabling intuitive and precise length adjustment, while maintaining a secure, comfortable, and easy-to-use fit.

Diagram of alternating magnet polarity along the strap and the resulting magnetic force

Gear up

Both straps follow a simple interaction flow – wear > pull to tighten > secure – creating an intuitive and efficient user experience.

The wrist tracker strap is designed to form a loop, enabling users to put the tracker on with single hand, without the assistance from store staff.

The ankle tracker strap is designed to be worn on the outside of ankle, allowing full range of motion and natural bending during gameplay.

Protective flaps

Protective flaps on both wrist and ankle straps shield the magnetic fasteners from catching on other gear. Working alongside an array of strong magnets, the flaps provide an additional layer of protection that enhances fastening reliability, reducing the risk of accidental loosening during high intensity and fast paced gameplay.

Protective flap on the wrist strap being lifted away from the fastener

Protective flap on the ankle strap being lifted away from the fastener

CMF selection

Silicone was selected for its durability and flexibility, enabling the trackers to maintain a secure fit while resisting wear, cracking, and deformation over time.

Its water-resistant properties and ease of cleaning make it ideal for wearable applications, where sweat and dirt can accumulate during regular use. This ensures the trackers remain hygienic and suitable for repeated use.

In addition to its practical advantages, silicone provides a soft, comfortable surface against the skin, enhancing the overall user experience. A dark grey matte finish was chosen to create a premium aesthetic while allowing the player colours to stand out clearly.

Render of the tracker in dark grey silicone with a blue player colour

Branding

A raised logo on the underside of the device temporarily leaves an imprint on player’s wrists after use. This creates a memorable interaction with the product while reinforcing brand identity in a subtle and playful way.