Tesla FSD and Autopilot on Snowy Highways: Navigating Invisible Lane Markings

When driving on snow-covered highways with Tesla's Full Self-Driving (FSD) or Autopilot, a common concern is whether the vehicle adheres to the vehicle tracks left by the car in front if lane markings are unclear. In such challenging winter conditions, the car’s capability to identify and follow lane markings becomes paramount. This article delves into the complexities of snow-covered roads and how Tesla’s advanced driving technologies adapt during such conditions.

Understanding the Challenges of Snowy Driving

On January 27, 2020, Ira J Perlow shared his experience driving home from the office in Denver during one of the worst winter driving weather conditions. The visibility was near zero, and snow and ice made the roads slippery and difficult to navigate. This situation highlights the importance of understanding how Tesla’s vehicles, particularly FSD and Autopilot, handle such conditions. In clear or white road conditions, Tesla’s system performs well. However, when snow obscures the lanes, the car’s ability to maneuver presents a complex challenge.

The Role of Lane Markings and Ruts

In conditions where lane markings are invisible or obscured by snow, Tesla’s Autopilot system relies on other visual cues to navigate. In snow-covered roads, the car may follow ruts formed by preceding vehicles. However, this can pose a problem if not all drivers maintain the same lanes, leading to a situation where the car’s navigation system conflicts with the prevailing driving patterns. This can result in behaviors that are not aligned with other drivers, potentially leading to confusion and unsafe driving scenarios.

FSD and Autopilot Behavior in Snowy Conditions

The car’s adaptation to snowy conditions involves several factors:

The system may have difficulty identifying the lines, leading to quick corrections when on dry pavement to center itself in the lanes.

When lane markings are clearly visible, the car will follow them even if they are nearly invisible to the human eye.

Under spotty snow cover, the car locks onto intermittent lines and follows them, even if other drivers are using different lanes.

Human vs. Automated Decision-Making

In severe weather conditions, human drivers often deviate from standard lanes, creating a more confined driving space. This behavior, while sensible for safety reasons, poses a challenge for Tesla’s automated systems. During Ira’s journey, he observed that the road was effectively divided into two lanes even though it was a three-lane highway. The car, relying on clear lane markings, maintains its position, potentially creating a conflict with human drivers.

Impact on Safety and Traffic Flow

The Tesla’s adherence to the real lane markings, even when they are nearly invisible, can enhance safety by maintaining a consistent driving pattern. However, it can also lead to conflicts with other drivers who may be using different lanes. The car’s inability to “blend in” with the array of driving behaviors can create stress for human drivers, who are already navigating difficult conditions.

Managing Tesla’s Autonomy in Snow

To mitigate these challenges, many Tesla owners opt to disable Autopilot functionality in snowy conditions. The 4-wheel independent torque control and traffic-aware cruise control can be effective in maintaining safe speeds and following distances. However, when the situation calls for following the leader or adapting to lane deviations, manual intervention becomes necessary.

Conclusion

In summary, snow-covered highways present a unique challenge for Tesla’s FSD and Autopilot systems. While the car’s ability to navigate based on lane markings can enhance safety, it can also lead to conflicts with human drivers. The solution lies in understanding the limitations of these systems and adapting driving behavior accordingly. Reliance on human judgment in such conditions is crucial to ensure optimal safety and traffic flow.