Hyundai Patents Subway-Style Doors for Self-Driving Cars

Robotaxi companies have been quietly battling an unexpected problem: passengers keep leaving doors open.

Waymo, the self-driving car service, has been paying towing companies around $20 per call just to go close doors that riders didn't shut completely. It's a surprisingly common issue that leaves expensive autonomous vehicles sitting idle until someone can physically fix the problem.

The company promised a solution was coming with future models featuring automatic doors similar to minivans. Now Hyundai, one of Waymo's vehicle partners, may have delivered exactly that.

Hyundai just received a patent for double-sliding car doors inspired by subway train systems. The doors pop up and slide automatically using a motor-driven system with gears, pulleys, and belts working together.

The patent describes a sophisticated setup where an electromagnet controls clutches that either engage or disengage the door mechanism. When passengers exit, the system could automatically ensure doors close fully before the car moves to its next pickup.

Patent drawings show a compact vehicle that looks purpose-built for autonomous taxi service. The design resembles other dedicated robotaxi models like Zoox, suggesting Hyundai is thinking beyond adapting existing cars.

The Ripple Effect

This seemingly simple fix could accelerate robotaxi adoption in cities nationwide. Every minute a vehicle sits waiting for a door to be closed is lost revenue and reduced service capacity.

More importantly, it removes a barrier between current autonomous technology and truly driverless operation. If cars need humans to bail them out of basic situations like open doors, they're not really autonomous yet.

The subway inspiration makes perfect sense. Train systems have been automatically managing doors and passenger flow for decades with remarkable reliability. Applying that proven technology to individual vehicles could make robotaxis as dependable as public transit.

Hyundai already supplies IONIQ 5 vehicles to Waymo's fleet, though those current models use traditional doors. This patent suggests the partnership is evolving toward purpose-built autonomous vehicles designed from the ground up for rider convenience and operational efficiency.

As self-driving cars become more common in cities like San Francisco, Phoenix, and Los Angeles, these small details matter enormously for making the technology work at scale.

Sometimes the biggest breakthroughs come from borrowing ideas that already work and applying them somewhere new.