Engineering Design of Wink Solutions’ Currency Sanitiser Machine
Developing rapid public health technology during the peak of the COVID-19 pandemic required uncompromising mechanical ingenuity. Partnering with Wink Solutions, KEVOS® executed full mechanical CAD modeling, prototype coordination, and Design for Manufacturability (DFM) for an innovative currency sanitiser. Featuring a sophisticated dual-path system—handling fragile paper notes and durable metal coins simultaneously—this compact machine delivered high-efficiency UV and thermal disinfection for global high-traffic retail and banking environments.
Executive Summary
project profile & parametersThe rapid transmission of pathogens via physical currency created an urgent demand for a non-destructive point-of-sale disinfection solution. The core engineering challenge was structural variance: treating delicate paper banknotes without tearing, alongside heavy metal coins that require robust thermal tumbling. Utilizing Autodesk Inventor, our team engineered a high-efficiency, dual-path internal architecture. We transitioned early concepts through physical prototyping validation into a highly modular, scalable design tailored for mass production during a global supply-chain crisis. The successful engineering secured significant national media attention and validated a commercially viable product deployment.
A single sanitization mechanism destroys fragile notes or fails to clean durable coins. The mechanical architecture must feature dedicated, independent physical pathways tailored to the material's specific threshold.
- Design a soft-roller feed path to secure complete UV exposure for banknotes.
- Engineer a heat-assisted tumbling mechanism for high-tolerance metal coins.
- Execute rigorous DFM to reduce total part count and streamline assembly.
Visual Knowledge Map
concept-to-prototype lifecycleBuilding physical test units to calibrate roller tolerances and test user interaction flows.
Core Concepts
public health engineering definitionsDual-Path Architecture
An internal mechanical layout featuring completely separate processing routes for paper notes and metal coins within a single compact chassis.
Design for Manufacturability (DFM)
Optimizing part geometries, materials, and assembly processes in CAD to reduce production costs and bypass supply chain shortages.
Soft-Roller Feed
A precision-tensioned mechanical drive system that feeds fragile paper banknotes smoothly past UV lamps without tearing or jamming.
Heat-Assisted Tumbling
A durable mechanical rotary path exposing all sides of heavy metal coins to high thermal ranges for complete sanitization.
UV Geometry Optimization
Calculating the exact distance and angle of UV-C light sources in CAD to guarantee 100% surface exposure on moving currency.
- Maximizes pathogen destruction
- Minimizes shadowing
Modular Serviceability
Designing internal sub-assemblies as quick-release cartridges, drastically reducing downtime when servicing public-facing machines.
Autodesk Inventor
The primary 3D CAD modeling software used to generate, simulate, and refine the mechanical components of the machine.
Rapid Prototyping
Building functional physical units quickly with an external partner to test and validate theoretical CAD mechanics.
Frameworks & Models
mechanical & DFM validationThe Currency Handling Split
Allocating dedicated processing mechanics based strictly on material thresholds guarantees non-destructive handling for both fragile paper and heavy metals.
DFM Risk Mitigation Matrix
Note Tearing
Prevented via calibrated soft rollers
Incomplete UV
Solved via optimized chamber geometry
Supply Shortages
Bypassed via part-count reduction
High Downtime
Cut via modular internal architecture
Prototyping Cycle Evaluation
| Design Metric | Early Prototype Phase | Final DFM Production Phase |
|---|---|---|
| Part Complexity | High (Custom, complex geometries) | Low (Standardized, injection-ready parts) |
| Maintenance Access | Difficult (Requires full tear-down) | Simple (Modular plug-and-play cartridges) |
| Sanitization Reliability | Variable (UV shadowing issues) | Absolute (100% calculated coverage) |
| Production Viability | Cost-prohibitive at scale | Highly economical and scalable |
Product Delivery Lifecycle
System Variables: feed tension · thermal output · UV exposure angle · assembly times.
Process Flow
design, test, and optimization methodologyThreat Identify
Establish public health requirements for cash sanitization.
CAD Modeling
Build initial mechanical architecture in Autodesk Inventor.
Dual-Path Design
Separate paper note rollers from coin tumbling tracks.
Prototype Build
Fabricate physical test units with an external partner.
Calibration
Adjust roller tension and optimize UV chamber geometry.
DFM Execution
Reduce total part count and design for mass manufacturing.
UX Refinement
Improve exterior form factor for intuitive public interaction.
Media Launch
Release validated system for national TV coverage and deployment.
Relationship Diagram
engineering to deployment impactDependencies & Interactions
mechanical system boundariesBanknote integrity depends on roller pressure tension — exact mechanical calibration prevents jamming or tearing of fragile paper.
Coin sanitization depends on thermal tumble paths — aggressive heating requires specialized internal materials to prevent chassis warp.
Pathogen destruction depends on UV chamber geometry — precise light angles and distances are required to ensure 100% surface exposure.
Service speed depends on modular architecture — designing internal systems as drop-in cartridges minimizes maintenance downtime in retail.
Manufacturability depends on part count reduction — consolidating components bypasses supply chain risks and lowers assembly costs.
Public adoption depends on compact form factor — creating an intuitive, small-footprint device encourages use in crowded banks.
Key Takeaways
essential project lessons- Separate paths are necessary — designing a dual-path system guarantees optimal, non-destructive handling for mixed materials.
- DFM is critical during crises — reducing part complexity is the only way to scale production amid global supply chain shortages.
- Prototyping catches flaws early — physical test units are essential to validate theoretical UV and thermal calculations.
- Modularity reduces downtime — engineering internal cartridges ensures rapid field servicing for high-use public machines.
- Prioritize material durability — selecting robust, hygienic plastics ensures the chassis survives continuous public interaction.
- Simulate before physical builds — Autodesk Inventor simulations help map internal flow paths before cutting any prototypes.
- Design for the end user — optimizing the exterior form factor guarantees an intuitive experience for bank tellers and cashiers.
- Media coverage proves relevance — strong engineering execution backed the founder's successful public health pitch on national TV.
Revision Sheet
high-impact review- The Task: Design a fast, reliable, non-destructive currency sanitiser for notes and coins during the COVID-19 pandemic.
- The Method: Execute full CAD modeling, rapid physical prototyping, and comprehensive Design for Manufacturability (DFM).
- The Value: A commercially viable, dual-path hygiene device ready for scalable mass production.
- System Architecture: Dual-path mechanics separating a soft-roller UV feed (for notes) from a heat-assisted tumbling track (for coins).
- DFM Execution: Intense part-count reduction and modularization to ensure the machine could be manufactured despite global supply constraints.
- Validation Loop: Iterative testing with external prototyping partners to calibrate mechanical tolerances and optimize UV exposure geometry.
- Public Impact: Delivered a compact, highly durable device that gained national media attention (featuring David Gardner) as a vital public health tool.
Quick Reference Table
engineering specifications| Mechanism Group | Operational Challenge | Applied Engineering Solution | Performance Yield |
|---|---|---|---|
| Banknote Handling | Tearing or jamming fragile paper currency | Precision soft-roller feed system | Smooth transit with 100% surface exposure |
| Coin Sanitization | Requires high thermal and mechanical force | Heat-assisted tumbling mechanism | Durable, thorough cleaning of heavy metals |
| Sanitization Chamber | Shadowing prevents full pathogen destruction | Optimized UV geometry and layout in CAD | Maximized UV/heat efficiency and safety |
| Mass Production | High costs and broken supply chains | DFM part reduction and modular architecture | Lower production costs and fast serviceability |
Frequently Asked Questions
clarifying the designWhy was a dual-path system necessary for this machine?
Paper notes and metal coins have vastly different physical thresholds. A single path that is aggressive enough to tumble and heat coins would shred delicate paper banknotes. Segregating them ensures both are cleaned safely.
How did the design prevent paper notes from tearing?
We engineered a highly calibrated soft-roller feed mechanism. By adjusting the grip tension and feed speed in prototyping, we ensured notes move smoothly without stretching or ripping.
Why was Design for Manufacturability (DFM) so important here?
The project launched during the COVID-19 pandemic when global supply chains were crippled. DFM reduced the number of custom parts needed, making the machine cheaper and easier to build locally at scale.
What role did physical prototyping play?
While CAD simulations are excellent, handling physical currency requires real-world friction testing. Prototypes allowed us to test and tweak the UV light angles and roller tolerances precisely.
What software was used to engineer the device?
Our team utilized Autodesk Inventor for all 3D mechanical modeling, functional simulations, and assembly packaging.
What was the impact of the national media coverage?
The televised interview with founding partner David Gardner highlighted the machine's critical relevance during the pandemic, validating the rigorous engineering behind it and driving strong commercial interest.
Memory Hooks
engineering tagsSegregate delicate notes from heavy coins to prevent damage.
Calibrate roller tension to guide fragile paper smoothly.
Cut down custom parts to bypass broken global supply chains.
Design internal cartridges for quick-swap retail maintenance.
Practical Applications
industrial use-casesBank Teller Stations
Deploying compact sanitizers at teller windows to protect staff handling high volumes of deposited cash.
Point-of-Sale Hubs
Integrating rapid sanitization devices into supermarket checkout lanes to protect daily retail consumers.
Transit Ticketing
Installing robust coin-tumbling systems inside high-traffic subway and bus terminal ticketing offices.
Rapid Prototyping
Using 3D printing and test rigs to validate mechanical friction points before cutting expensive production molds.
UV Geometry Mapping
Calculating precise lighting angles in CAD to ensure 100% pathogen eradication without shadowing.
DFM Crisis Scaling
Applying part-reduction strategies to manufacture complex machinery during global material shortages.