Mechanical & wearable engineer needed for prototyping a wearable water safety device.

Soft goods & mechanical engineer to develop a wearable inflatable rescue device I'm building a wearable device that can inflate a 50N rescue float from a small armband in seconds, with no compressed gas, no cartridge and no pressure vessel anywhere in the product. The chemistry is done and validated. What I need now is someone who can help me turn it into a real, wearable, manufacturable product. We have lifeguards interested, swimmers interested, parents interested and the general public. We think we can make something amazing out of this and make water safety as universal as helmets. Together, we can save thousands of lives. Roughly 120 mL of two harmless liquids sit in two sealed chambers. You pull a cord, the separator between them is removed (I imagine a system sort of like where pulling it makes holes align to remove between the two chambers), they mix, and the reaction generates about 5.2 L of CO₂ that inflates a folded bladder. The bladder then releases from the armband onto a tether so it floats in front of the user's chest, where they can hold onto it like a rescue tube. I am looking for textile, soft goods, wearable and mechanical engineering help to design, prototype and iterate that physical product, and to do it in a way that gets cheap, light and mass-manufacturable, not just clever and expensive. We want to save lives and we want to make it cheap - let's do it together! Why this matters Drowning is one of the few major causes of preventable death that has barely moved in fifty years. Thousands of people die every year and millions get really close to death, or result with significant injury. Most die within metres of safety, with people losing consciousness as quickly as two minutes. A large share of drownings happen outside patrolled hours or away from the tower, where no lifesaver is coming. The other brutal statistic is that a significant number of drowning deaths are the would-be rescuers — untrained bystanders who went in without flotation. I'm a patrolling surf lifesaver, rescue boat driver and patrol captain. I've done this work. The first rule of every rescue is that you never enter the water without something that floats, and the reason people drown is almost never that flotation is expensive or complicated. It's that it's inconvenient enough that they leave it at home. People don't like big lifejackets or even tiny pouches like Restube (please research them). They draw attention, bounce around, look silly, and affect swimming. I want to remove the inconvenience. The goal is a device cheap and comfortable enough that wearing one is as unremarkable as putting on a bike helmet. Why the chemistry approach is the whole point: Every comparable product on the market — Restube, Kingii, Minifloat Ltd — uses a compressed CO₂ cartridge. That constraint is what I've removed, and it changes almost every downstream decision: No cylinder. No compressed gas means no dangerous goods classification, no airline restrictions, no cylinder re-certification, no cartridge to replace or forget to replace. Long shelf life is already solved. The chemicals themselves comfortably achieve 5+ years of stable shelf life. I'm a chemist and physicist myself so the science and modelling is done and set. But I just am very bad at building. The end device can be extremely cheap. No pressure vessel, no valve, no regulator. The bill of materials can go somewhere cartridge devices can't follow. Retail-friendly. It can ship in a padded envelope, sit on a shelf, and go in carry-on luggage. If anyone tells you a 5 L bladder can't pack down into an armband, those three companies, especially Minifloat Ltd, are the existence proof that it can. Where I'm up to: Done, settled: Full chemistry developed and validated, a two-liquid, extremely safe system. You will not need to touch the chemistry unless specific challenges arise in which case I will work through the chemistry with you; that's all on me. ~120 mL of liquid producing ~5.2 L of CO₂ (120mL is overall liquid. It's not that both reactants are 60mL, they have slightly different volumes - but that I can only share later). A custom Venturi flowmeter with Arduino/Python data logging, so I have real gas evolution rate and cumulative volume curves to prove the volumetric flow rate. However, the flow rate will also be heavily dependent on the reaction chambers you design. Company incorporated in Australia, IP assigned in, patent landscape analysis complete, patent strategy underway. An open co-design and early-customer pathway with Surf Life Saving Australia. Not done: this is the challenge for you: Everything between "the chemistry works on a benchtop" and "a manufacturable product on a human arm." Should be a fun and rewarding challenge! The system should be pretty simple - I have designed the chemistry to be perfect for you to just build around it, simply. We are also interested in incorporating GPS sensors into it, to track athletes who may wear it, or surf life savers. But that's an additional thing and one that we would like to see in the future. Scope of work: There will likely be many design cycles and iterations, and we're happy to discuss and be flexible with the budget. 1. The bladder ~5 L inflated, crescent/tube geometry, ~120 mm inflated thickness, shaped to be held against the chest like a rescue tube. Must have a tiny clip on the end of it that's furthest away from the attachment chord (the chord that holds the bladder to the armband after inflation, so it stays with the swimmer) so a rescue can clip the crescent bladder across back onto the rope and tow the victim back to shore. Must fold and pack down to a fraction of that volume. I would love to explore vacuum-sealed packing. Must inflate reliably from folded without self-strangling, tangling, or leaving unfilled lobes. My current lead candidate is metallised foil balloon film: heat-sealable, extremely cheap, and flex-crack isn't a concern because the device is single use. Possibly in a bladder-in-shell architecture with 20–30D ripstop. Please challenge this. I want your materials judgement, not my assumptions repeated back. Seam design, weld process (heat / RF / ultrasonic), and how that seam survives a panicking adult grabbing the float. 2. Pack, fold and deploy The fold pattern is probably the hardest single problem here. Airbag, parachute, packraft and inflatable SUP folding logic all apply. Target: functional buoyancy in under 10 seconds, stretch goal under 5. Liquid and foam carryover is a known risk. A vigorous liquid–liquid gas reaction foams. I need a trap, baffle or separator so liquid doesn't slug into the bladder or block the outlet. I'd love to hear how you'd approach this. 3. Tether and release This is a hard functional requirement, not a nice-to-have. A buoyant bladder fixed to the arm lifts the arm forcefully and that's a big issue in surf. We have to release the bladder onto a tether after inflation, so the float ends up in front of the user. Tether attachment has to take the shock load of a panicking adult grabbing and pulling. Must not snag, tangle around limbs, or release early during normal swimming, paddling or surfing. Tether length, swivel and stowage all need designing. 4. Reaction chamber and trigger Likely needs a clear path to injection moulding at volume. The chambers should be soft - the chemicals are safe and won't affect degradation. I'm thinking something like silicone or whatever material heat shrink is made from. It's flexible, but it's watertight and holds well. A hermetic seal in storage across a realistic temperature range, like a car boot in a Queensland summer and a Tasmanian winter. The separator has to hold a perfect seal for years, then release with deliberate force: one hand, cold and numb fingers, possibly without looking. Open architecture question: one dual chamber, or an array of multiple small parallel reaction chambers? Multiple chambers might buy faster mixing, faster gas evolution and a better fold factor at the cost of complexity. I want your view on this. 5. The wearable A small, low-profile armband. Comfortable enough that someone wears it all day at the beach and forgets it's there; that's what will make people actually want to wear it. Stays put during swimming, surfing and paddling without cutting off circulation. Sizing across a wide range of arm circumferences, including children. A simple way to attach it to the arm. Velcro actually turns out to be a huge challenge... Try putting Velcro around your arm and you'll see. It's a weird challenges but I'm thinking something like those snap-on wristbands could be absolutely amazing. In either case the goal is that it goes on tight, using minimal effort and just one hand. Outer shell: lightweight, thin and soft; crushed neoprene is something I've been considering. Saltwater, UV and abrasion resistant. The surface needs to be customisable and printable. Club colours, school branding, corporate and event runs are a core commercial channel. Let's make it so we can make it look cool and pretty. 6. Manufacturability and scaling — the thing I care about most Every decision gets judged against this. This is not a boutique product. Minimal part count, minimal process steps, minimal exotic materials. Cheap tooling that's easy to duplicate. An honest scaling path from 10 units → 1,000 → 100,000, including where processes change and what that costs. Assembly and fill process design, including how you load two liquids into a sealed device repeatably and safely at volume. Single-use disposal: minimal material, minimal waste, ideally recyclable or benign. The spent chemistry is food-grade adjacent and I'd like the product to match that. Targets These are my current theatrically achievable numbers. Inflated volume: ~5 L (≈50 N buoyancy, comparable to an ISO 12402 Level 50 buoyancy aid) Liquid payload ~120 mL total, two liquids Gas generated ~5.2 L CO₂ Time to functional buoyancy Less than 10 s (stretch: 5 s) Total worn mass Less than 300 g (stretch: less than 250 g) Packed envelope ~270 × 75 × 35 mm or better Operating water temperature 5–50 °C Activation One hand, no visual, works with numb fingers Book of materials at volume (100k units) Aggressively low, happy to discuss specifics once we're talking Another target is the incorporation of a GPS system into these so people can track where lifesavers are, if lifesavers wear them, or people can use it for tracking of exercise. Skills I'm looking for (but it's ok if you don't have all of them! I'm a strong believer that you can learn anything with enough time and effort): Hands-on inflatable or soft goods engineering. Life jackets, drysuits, inflatable SUPs, medical inflatables, evacuation slides, airbags. Or just any kind of wearables; I want this to be as sleek and cool as a watch so if you've got experience with designing wearables, this could be good for you. Design for manufacture. Real experience taking a physical product from prototype to tooled, volume production, and support of a startup that's a social venture. Textile and materials engineering: film and laminate selection, coated fabrics, seam and weld engineering, saltwater/UV durability, cost engineering. Mechanical and product design; the reaction chamber, separator mechanism, trigger ergonomics, tether release. Wearables and industrial design; armband ergonomics, sizing, aesthetics, the customisation surface. Automotive airbag or gas generator background. Water sports or marine background; do you like the beach? Do you like swimming? Have you ever been affected by drowning? Logistics: Milestone-based. I'd rather start with one small, well-scoped first milestone and expand from there than sign a large scope cold. Both of us get to find out how we work together on something low-risk. Remote. I'm in Australia; some overlap with AEST helps but isn't essential. I'm a night owl. Physical prototyping can be coordinated with shipped samples or hosted here. Long-term potential. This is a multi-stage product development programme, not a one-off task. For the right long-term collaborators, equity options alongside cash may be available. In case you're interested in equity options, I will quickly add: our revenue if we can achieve our vision, by 2031, is likely to be more than $20M. Budget and timeline: We are looking at less than $8,000 and a minimum viable product in 3-6 months, if not faster. An NDA and IP assignment will be part of the contract, but nothing is needed to have a first conversation. How to apply: Keep it easy. I'd much rather just have a chat and learn how you work, what ideas you have, and what you can bring to our team! If you're a mechatronics, mechanical, design, wearable or soft goods engineer, reach out! One last thing: Most engineering work makes something slightly faster or slightly cheaper. This one has a body count attached to the outcome. Every year, hundreds of thousands of people worldwide die with nothing that could have saved them. And it's because lifejackets aren't sleek; they are bulky, look silly and can actually be an issue on the beach when it comes to diving under waves. If we get this right, the thing you helped design ends up on arms at every beach, pool, river and lake, worn without a second thought, the way a helmet is. That's the job. I'd love your help building it.