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National Winner

Air Ring 48

A more ergonomic and biometric cooling accessory to protect outdoor workers from worsening climate-induced heat stress.

  • AR48.

  • When the world boils, the construction industry suffers the worst.

  • Design considerations in all aspects.

  • 48 generations of prototypes.

  • Frontline testing with construction companies. Contributing to each prototype's evolution.

What it does

60% of Hong Kong’s 600,000 construction workers have suffered symptoms of heat stroke. AR48's more ergonomic and biometric cooling system prevents heat stress, creates enjoyable working conditions, and recuperates valuable hours of productivity.


Your inspiration

Imagine you are doing very heavy deadlifts. It’s over 45°C. You feel your head slowly boiling while the safety gear you’re wearing is slow-cooking you inside out. But worst is the daunting feeling that you cannot stop: you are already behind schedule. This is the hellish reality for the construction workers in Hong Kong. Existing cooling solutions are unable to solve their problem. They are too heavy and imbalanced (waist fans), inconvenient and insecure (hand fans, neck), or inefficient (cooling towels). Thus it became our mission to design the most ergonomic and effective personal cooling device, tailored to the needs of construction sites.


How it works

Locked onto a safety helmet, AR48 induces a cooling sensation to the whole body by redirecting fan-induced airflow to cranial hotspots with medically-proven highest sweat rates: back neck, side neck and back of ears, while preventing the trigeminal nerves at the face that causes headaches. Our proprietary cooling technology is proven in trials to generate a -3.20°C maximum skin temperature difference and -0.67°C core temperature difference. Such efficient, targeted cooling consumes less energy, enabling 16-hrs use per charge. It possesses an ultra-ergonomic design. At 150g, it is balanced and obstruction-free. Allows 100% flexibility of head movement, no hindrance while working. Low power requirement enables it to operate at 30dB (comparable to whispers). Intelligent buckle design enables a 5-second installation process. Adaptable across all helmets, and can be used as neck fan. It is waterproof, impact resistant, and compliant with site safety standards.


Design process

AR48 = 48th prototype Year 1:Fans in straw hats then safety helmets. Mechanical components compromised safety, so design became add-on accessory Year 2:Experimented cooling tech: heat sinks,cross-flow fans,liquid cooling etc. Axial fans were most effective. Biometric studies showed back of neck as hotspot So design attached to back of helmet with a "redirector" to channel airflow. Did smoke tests, ANSYS simulations, and improved helmet locking system H40:Larger redirector to cool helmet interior and back of neck. Battery in front for better balance. Trials with Chun Wo Dev.Ltd.(HK) and M&S Construction(Ghana). Workers wanted cooling at back of ears H43:Ring configuration for better balance, avoiding blocking helmet fastening wheel. Two smaller fans target back of ears and neck, increased cooling duration to 30 hours, reduced noise and weight. New plugin mechanism. Trial with CWD Ltd H46:Optimized weight, new buckle mechanism, works as neck fan, enhanced redirector. Side pods for better aerodynamics. Trial with CWD Ltd AR48:Improved buckle mechanics, fan inlet design. Used MagLev fan. Enhanced redirector for comfort, bendable handle for different head sizes, magnetic attachment for shading fabric. Pending waterproofing and manufacturing trials w/China State Construction


How it is different

AR48 excels in all aspects of cooling wearables: More efficient cooling ability; small wind chill at the head's hotspot induces large body cooling sensation 2x lighter, more balanced, quieter than waist fans. More convenient and secure than hand-held or neck fans, more efficient than cooling towels (need frequent rinsing and only last 5-10 minutes) AR48 is superior to helmet-mounted fans like Tajima Seiryo 2 (TS2): Focusing on head hotspots, AR48 induces more body cooling than TS2, which cools only the helmet's interior AR48’s efficiency requires lower fan size and speed, resulting in less noise and vibration AR48 is more compact, allowing 100% head movement, unlike the bulky TS2 AR48 is 150g, balanced around the head, while TS2 is 305g, concentrated at the helmet's back, straining the neck AR48 fits all helmets, unlike TS2 which needs custom helmets AR48 costs less than HKD50/unit to manufacture, sold at HKD200, much cheaper than TS2 at HKD800 on eBay


Future plans

1. Design optimization of redirector and fans, maximize performance and comfort, assisted by Generative design and AI 2. coolant booster material science and mechanics, facilitate heat removal from the body to multiply the cooling effect 3. manual winding mechanism for sustainability and battery-free convenience After equipping the 600,000 workers in Hong Kong with our cool-tech, we aim to expand this benefit to the rest of 229 million workers worldwide. In tandem, we also hope to expand the tech into fashionable wearables for the general public, such that everyone can enjoy life outdoors under worsening global warming.


Awards

HKU iDendron Incubation program HKU iDendron SEED program CityU HK Tech 300 program Tam Wing Fan Innovation Fund Winner of HKU InnoShow 3 Years of FULL membership of HKU Innowing Tam Wing Fan Innovation Fund HKSTP IDEATION Programme Chosen for exhibition at Hong Kong Convention and Exhibition


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