{
    "title": "Electronic Wedge Brake (Siemens Electromagnetic Wedge Brake)",
    "inventor_name": "Bernd Gombert",
    "publication_year": 2006,
    "device_name": "Electronic Wedge Brake (EWB)",
    "goal": "Provide a more efficient, faster-acting braking system that uses far less energy than conventional hydraulic brakes.",
    "problem_addressed": "Hydraulic brakes require high actuation energy, have slower response times, need fluid lines and a master cylinder, and lack fine-grained electronic control.",
    "concept_summary": "The Electronic Wedge Brake replaces the hydraulic actuation with a small electric motor that pushes a brake pad against a rotating disc via a series of interlocking triangular wedges. The kinetic energy of the rotating disc self-boosts the wedge position, increasing braking pressure automatically as vehicle speed rises. Sensors and a torque controller manage the pad position, providing brake-by-wire control, ABS-like anti-lock functionality, and electronic stability control without separate hydraulic components.",
    "detailed_description": "Each wheel has a control unit containing a brake pad, a mechanical transfer system, two precision electric motors, and multiple sensors (wheel speed, wedge position, force). The motors move the pad over rollers on an inclined wedge surface; the wedge's geometry converts the disc's kinetic energy into additional braking force (self-energizing). The system runs on the vehicle's 12-V electrical network, can respond in ~100 ms, and claims to use only one-tenth the energy of hydraulic brakes while reducing stopping distance by more than 50 %. A prototype demonstrated these benefits at the International Motor Show in Frankfurt, and a major European automaker is a pilot customer.",
    "category": "Mechanical Engineering",
    "principles": [
        "Electromagnetic actuation",
        "Self-energizing wedge mechanism",
        "Feedback control",
        "Brake-by-wire",
        "Torque sensing"
    ],
    "scientific_domains": [
        "Mechanical Engineering",
        "Electrical Engineering",
        "Automotive Engineering"
    ],
    "mechanisms_of_action": [
        "Electric motor drives brake pad laterally",
        "Wedge geometry converts disc rotation into additional pad pressure",
        "Sensors measure wheel speed and wedge position",
        "Control algorithm adjusts motor output to achieve desired braking torque"
    ],
    "materials": [
        "Metal brake disc",
        "Plastic brake pad",
        "Steel wedge",
        "Aluminum housing"
    ],
    "energy_sources": [
        "Vehicle 12-V electrical system"
    ],
    "inputs": [
        "Driver brake pedal command (electrical signal)",
        "Vehicle speed / wheel rotation",
        "Wedge position feedback"
    ],
    "outputs": [
        "Braking torque",
        "Wheel deceleration"
    ],
    "claimed_performance": "Uses ~10 % of the actuation energy of hydraulic brakes; prototype required less than half the stopping distance of standard brakes; response time ~100 ms (vs 140-170 ms for conventional ABS).",
    "experimental_evidence": "Prototype tests reported at Siemens press release and at the International Motor Show in Frankfurt showed the wedge brake achieving < 50 % stopping distance compared with standard brakes; a company official claimed a 10x energy reduction.",
    "replication_status": "Prototype demonstrated; pilot testing with a major European automaker; no independent third-party replication reported.",
    "keywords": [
        "electronic wedge brake",
        "brake-by-wire",
        "self-energizing brake",
        "Siemens VDO",
        "electric motor actuation",
        "ABS replacement"
    ],
    "related_technologies": [
        "Hydraulic brake systems",
        "Anti-lock braking system (ABS)",
        "Electronic stability control (ESC)",
        "Brake-by-wire"
    ],
    "controversy_level": "low",
    "confidence_score": 0.85,
    "practicability_score": 0.7,
    "fringe_score": 0.2,
    "evidence_strength": 0.6,
    "risk_score": 0.2,
    "trl_estimate": 5,
    "source_urls": [
        "http://www.autoweek.com/apps/pbcs.dll/article?AID=/20061109/FREE/61106011/1065",
        "https://www.youtube.com/watch?v=6KMdT3iaFdQ",
        "http://www.siemens.com/innovation/en/publikationen/publications_pof/pof_fall_2005/auto_electronics/braking_systems.htm"
    ],
    "organizations": [
        "Siemens VDO Automotive",
        "eStop",
        "German Aerospace Center (DLR)"
    ],
    "applications": [
        "Passenger cars",
        "Heavy-duty trucks",
        "High-speed trains",
        "Electric and hybrid vehicles"
    ],
    "limitations": [
        "Reliance on vehicle electrical power; failure of power supply could affect braking",
        "Complex sensor and control electronics increase system cost",
        "Long-term wear of wedge and pad not yet proven",
        "Integration with existing vehicle safety standards required"
    ],
    "open_questions": [
        "How does the wedge mechanism perform under extreme temperatures and high-load conditions?",
        "What is the lifecycle cost compared with traditional hydraulic brakes?",
        "Can the system meet all regulatory safety certifications for passenger vehicles?",
        "What are the maintenance requirements for the wedge and motor assembly?"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "In tests, a prototype with the wedge brakes regularly required less than half the distance to come to a complete stop than the prototype with the standard brakes, a company official said.",
        "The EWB only requires one tenth of the actuating energy required by today's hydraulic braking systems.",
        "It takes around 100 ms for the EWB to generate full braking power, compared with 140-170 ms for a conventional ABS.",
        "The system runs on the standard 12-volt electrical system found in most cars.",
        "A demonstration at the International Motor Show in Frankfurt showed the principle of the electronic wedge brake."
    ]
}