Mercedes adds a new car light color: Blue for self-driving
Mercedes is introducing turquoise exterior lights to indicate when its Level 3 “Drive Pilot” system is controlling the car, initially in California and Nevada where this mode is legal in low-speed highway traffic. Commenters debate whether a new light color for autonomy is useful or confusing, raising concerns about similarity to green traffic signals and police blue lights, visibility for color‑blind people, enforcement, and potential misuse by non-autonomous cars. Others see it as a sign that self‑driving technology and regulation are maturing, but question whether such a prominent visual signal is warranted for what is essentially non-critical information to other road users.
Color choice and potential confusion
- The lights are actually turquoise, not blue; defined by SAE to differ from police blue.
- Many argue turquoise is too close to existing greens and blues:
- Could be mistaken for police lights, traffic lights, aftermarket headlights, or even reverse lights, especially under varied lighting and for some vision types.
- Others counter that experts explicitly analyzed color options (including purple) and selected turquoise based on visibility and discrimination studies.
Accessibility and visibility
- Several color‑vision‑deficient participants note difficulty distinguishing certain greens, yellows, and turquoises.
- One critique: the final chosen shade is closer to green and may be confused with white by common forms of red/green colorblindness, potentially overlapping with reverse/brake clusters.
- Supporters cite the SAE work claiming turquoise outperforms alternatives (like purple) in central-field visibility and for users with color vision deficiencies.
Purpose and necessity of a self-driving light
- Stated goal: signal that the vehicle is under “conditionally autonomous” control so police and others don’t misinterpret a disengaged driver as illegal behavior.
- Some see this as a useful “pilot lamp” for autonomy and potentially helpful for pedestrians and other drivers.
- Others view it as non-critical “nice to know” info that consumes a scarce, highly visible spectrum band for marginal benefit, possibly driven by marketing.
Legal, enforcement, and misuse concerns
- Expectation that turquoise will be legally reserved for that driving mode, analogous to brake lights or emergency blues.
- Concerns about enforcement: aftermarket adoption, verifying whether a car is actually in self-driving mode, and the need for databases, cameras, or transponders.
- Some foresee privacy and equity pushback to camera-based enforcement.
Autonomy levels, liability, and safety
- Some excitement that Mercedes’ system allows eyes-off driving in traffic jams and signals real progress toward full self-driving.
- Others warn Mercedes is assuming major liability by explicitly allowing drivers to look away, unlike systems that keep liability on the driver.
- Comparisons with Waymo rear-end scenarios suggest signaling and brake-light behavior can materially affect safety.
Ideas for broader signaling changes
- Several propose additional standardized signals: “thank you/go ahead,” front brake lights, clearer turn indicators (especially for cyclists), and better placement/colour of turn signals.
- Discussion broadens into criticism of US signaling conventions (e.g., red rear turn signals) and confusing systems like HAWK pedestrian signals.