Industrial HMI redesign
Transforming SCADA system complexity into accessible interfaces for operators under pressure
Case study
Industrial HMI redesign
The Challenge
The system had power (reporting, diagnostics, recipe management), but most features went unused. The interface tried to be everything to everyone, all at once, and ended up serving no one well. Operators took 1 month to learn recipe management. Critical alarms got lost in visual noise. Powerful reporting tools had <10% adoption. Different interfaces across the product family confused operators.
When production lines process thousands of panels per day, a confusing interface isn't just frustrating, it's expensive. I worked with a leading European manufacturer to redesign their SCADA system: the brain that monitors and controls industrial painting and coating production lines worldwide.
This is the story of making industrial complexity accessible to human operators under pressure.
"The challenge: designing one interface that serves three different worlds: a software engineer troubleshooting remotely from Germany, a service technician commissioning equipment on a factory floor, and a machine operator managing real-time production. When something goes wrong on a line processing 50 panels per hour, every second of confusion costs money."
"Many things are more for decoration than utility." - Software Technician. Physical-digital disconnect created dangerous ambiguity in critical moments. Operators reset alarms with physical buttons but the digital interface didn't clearly show what happened or current system state.
Operators were working around the system, not with it. They mostly watched the real line and only glanced at the screen when something seemed wrong. Recipe management took weeks to learn due to mental model mismatch between ordered machine lists and spatial physical layouts.
Research
Stakeholder Interviews
"I mostly watch the real line. I glance at the screen when something seems wrong."
— Machine Operator
Operators don't want data, they want answers
Interface showed velocity indicators, production cadence, photocell statuses: dozens of data points. But operators didn't need to know everything was running smoothly (they could see that). They needed instant clarity when problems arose.
Recipe Management: Month-Long Learning Curve
Setting machine configurations was so complex that even experienced operators took weeks to feel confident. Interface showed ordered list of machines, but operators thought in spatial layout: 'the third oven I walk past.'
The Duality Game
Critical Disconnects Revealed
Surfaced gaps between what developers thought was important and what operators actually used. Standard interviews weren't revealing the full picture in high-pressure environments.
Physical-Digital Button Mapping Gap
Operators reset alarms with physical blue button, but digital interface didn't clearly show: what the button did, current system state, or what would happen next.
Contextual Analysis
Context Changes Everything
Small facilities: Deep engagement with all features. Large facilities: Minimal interaction, maximum clarity needed. One size didn't fit all.
Spatial Thinking Dominates
Operators navigate by physical layout, not abstract lists. The interface must map to their mental model of walking through the facility.
Key Insights
Monitoring ≠ Reporting
These are different modes requiring different interfaces. Real-time monitoring needs instant problem recognition. Historical reporting needs analytical depth. Trying to combine them created confusion.
Spatial thinking dominates
Operators navigate by physical layout, not abstract lists. The interface must map to their mental model of the factory floor: the third oven I walk past, not Machine_ID_3.
Progressive disclosure prevents overload
Show what's needed now, reveal complexity when required. 40+ simultaneous data points overwhelm. 12 essential indicators with progressive disclosure enable quick assessment.
Consistency enables efficiency
Operators often work across multiple machines. Inconsistent interfaces multiply training time and increase error probability.
Goals & Principles
Instant problem recognition
Abnormal states immediately visible without requiring data interpretation. Reduced assessment time from 10 seconds to 2 seconds.
Spatial mental models
Interface matches physical layout that operators walk through every day. Recipe management uses visual floor plan representation.
Role-based experiences
Different views for operators (monitoring focus) vs technicians (diagnostic depth) vs engineers (system configuration).
Ecosystem consistency
Unified experience across entire product line reduces training requirements and operator confusion.
Guiding Principles
Clarity over completeness
Better to show less with perfect clarity than everything with ambiguity. In high-pressure moments, clarity is the entire job.
Spatial over sequential
Match how operators think about physical space rather than abstract database structures or technical hierarchies.
Progressive over parallel
Reveal complexity progressively as needed, not simultaneously overwhelming users with all options upfront.
Solution Design
Streamlined Synoptic View
Information overload in main monitoring screen: 40+ data points visible simultaneously with no visual hierarchy, critical information buried.
Reduced to 12 essential indicators with progressive disclosure for details. Added color coding for system states and enlarged critical warnings.
Operators could assess system state in 2 seconds vs 10 seconds. They don't need to know everything is running smoothly: they can see the real line. They need instant clarity when problems arise.
Spatial Recipe Interface
Month-long learning curve for recipe management due to abstract machine lists that didn't match operator mental models.
Created visual floor plan representation with drag-and-drop on spatial layout, visual indicators for dependencies, and template library for common configurations.
Interface now matches how operators think: 'the third oven I walk past' instead of Machine_ID_3. Learning time reduced from weeks to days. Dependencies become visually obvious.
Physical-Digital Button Mapping
Unclear relationship between physical controls and digital states created dangerous ambiguity in critical moments.
Created comprehensive button-state schema with visual diagram showing physical buttons, digital state for each position, clear action feedback, and documented recovery procedures.
This became critical reference document bridging physical and digital worlds. Operators could understand system state at a glance and know exactly what each physical interaction would do.
Outcomes & Impact
Specific metrics withheld due to NDA
Assessment time reduced from ~10 seconds to ~2 seconds
Recipe learning time reduced from weeks to days
100+ page style guide and documentation delivered
7 sprint presentations documenting evolution
Dramatically simplified daily operator workflows
Reduced cognitive load during critical moments
Faster alarm recognition and response time
Intuitive recipe management matching mental models
Maintained diagnostic depth for technicians
Clearer troubleshooting pathways for service teams
Consistent experience across entire product family
Foundation for future development established
Reflections
What Worked
Custom Research Methods Revealed Hidden Insights
The Duality Game revealed stakeholder misalignments that traditional interviews missed. Getting developers and operators to negotiate priorities together surfaced critical disconnects.
Progressive Disclosure Strategy Succeeded
Hiding complexity until needed made the interface approachable without sacrificing power. Operators appreciated interfaces that grew with their expertise rather than overwhelming from day one.
Design System Approach Ensured Consistency
Creating reusable components ensured consistency across product family and accelerated future development. Investment in systematic design paid long-term dividends.
Challenges
Stakeholder Alignment Required Negotiation
Different user groups had conflicting needs. Required careful negotiation and clear trade-off documentation. Engineers wanted technical detail, operators wanted simplicity, service techs needed both.
Technical Constraints Affected Design Decisions
Legacy system limitations affected some ideal design decisions. Had to balance ideal design with technical feasibility and implementation costs.
Remote Collaboration During COVID-19
Pandemic meant remote research and design. Adapted methods for virtual engagement. Would have benefited from more on-site factory floor observation.
Key Learnings
Industrial UX is high-stakes design: when errors cost thousands per minute, clarity isn't optional, it's the entire job
Mental models trump clever design - The best interface matches how users think, not how engineers build systems
Documentation is design - In B2B contexts, your handoff documentation matters as much as the interface itself
Progressive disclosure works - Users appreciate interfaces that grow with expertise rather than overwhelming upfront
Physical and digital must connect - In industrial contexts, interface must acknowledge and integrate with physical controls