On Autopilot with Road Curves have Predictive Slowing


Now Implemented!


With Autopilot active, when approaching sharper curves, slow the car before the curve starts and accelerate before coming out of the curve. The speed reduction would be a combination of the car’s speed and the tightness of the curve, similar to how most humans drive.


On Autopilot the Tesla takes turns that are causing car sickness for my family. This is because it is trying to maintain speed along with the turn, but then when it detects a high turn rate then decelerates. This causes the opposite of what humans are expecting and maximizes the centrifugal (sideways-force Gs) of the turn.

The amount to slow down would be proportional to the expected centrifugal force of the turn for optimal comfort. For example, a 90-degree turn for a 5-foot circumference like a stop sign would slow to 10-15 mph. A 10-degree turn for a quarter-mile circumference on a highway at 65mph may only decrease one mph.

This would be useful for both sport and chill mode when using Autopilot


This has been improved significantly over the years, and we now consider it implemented in June-2021.

edited by moderator
Category: CY3XS Applies to:
     Created 28-Oct-2019


Yes, also the car should tend to move toward the inner side of the lane on a curve. Currently the car tends to veer towards the outside, which is particularly concerning on a right-hand curve with oncoming traffic. A human driver will tend to veer towards the inside of the curve.
    Created 1-Oct-2022
Most human drivers slow before entering a sharp curve.  Slowing in the curve could produce a skid.

    Created 2-Jan-2020
Agreed. The car should know the curvature in advance from the map and in advance of the curve it should replace the road speed limit with the minimum anticipated through the curve, say in a curve sign, that will allow some maximum centripetal acceleration - whether said centripetal acceleration be engineered or user adjusted.  It should slow smoothly.  Ideally it should assess each curve with an accelerometer and report to Tesla's map and/or in it's own curves list when roads are sloped to allow faster or require slower speed for a comfortable ride.
    Created 29-Oct-2019