Many Tesla owners who paid for FSD (Full Self Driving) were excited to find out that the FSD Beta test program was being expanded. CEO Elon Musk invited customers to apply to the program and informed them (us) that invitations would be prioritized based on driver behavior. To help make this happen, the company launched the Tesla Safety Score which rates each driver based on a set of driving behaviors. Musk promised, then delivered, the FSD Beta invitation to around 1,000 Tesla drivers who had scored a perfect 100 in their Tesla Safety Score over a two week period. Our editor Zach Shahan was one of these lucky few hundred-percenters who got the FSD Beta invitation and has already shared his initial impressions of the FSD software.
Musk tweeted that they would keep a close eye on the program for some time, then would open it up to more testers based on their scores: 100 first, then 99, then 98, and on down the line. So thousands of potential beta testers are still doing their best to maintain a high safety score so that they can help the company refine its FSD software and eventually deliver it into production. In order to do that, drivers first need to know how the Safety Score works and what we can do to maximize our scores.
What is the Tesla Safety Score?
The Tesla Safety Score is a numerical score from 0 to 100 evaluating a driver’s safety. Though the algorithm will undoubtedly be tweaked over time, it currently measures five elements which are considered essential for safe driving. These factors are weighted and combined in order to provide a single numerical score. Here are the five factors, ranked from most important to least important when calculating that score:
Forced Autopilot Disengagement – this is when the car shuts off Autopilot because you’re not paying attention. Considering that the company is selecting testers for beta software, it makes sense that this factor would be most important. Tesla is looking for drivers who are paying attention to their surroundings and the warning indications provided by the Autopilot system. As long as you keep your hands on the wheel and your eyes on the road, this penalty should be easy to avoid.
Hard Braking – this is when you apply “excessive force” while braking. “Excessive Force” by the current measurement is a G force in excess of 0.3g. In simpler terms, it means your vehicle decreases by more than 6.7 mph in one second.
Aggressive Turning – taking a turn too quickly. This is defined as more than 0.4g of lateral acceleration or an increase in the side to side motion of the car by more than 8.9 mph in one second.
Unsafe Following Distance/Time – if you are following a car so closely that you have only one second or less to react if the car in front of you comes to a sudden stop, this is considered unsafe and you will get negative points for unsafe following.
Forward Collision Warning – this is when the car detects an object in front of it that may cause a collision unless the driver intervenes. The specific value of this is measured by the number of front collision warnings that trigger per 1,000 miles of driving.
To understand how the scores are calculated, you need some additional information. Hard Braking, Aggressive Turning and Unsafe Following are all calculated as a percentage of that specific action. For example, your “aggressive turning” score depends on how long or how many times you exercise aggressive turns as a percentage of all turns. The same applies for hard braking and unsafe following. If you find that you’ve been dinged for “hard braking” then the only way to improve the score is to get back out there and concentrate on coming to a stop more slowly – repeatedly. The more you turn or brake or follow safely, the lower your individual score goes for these factors (in this case, lower is better).
Also, the company has stated that these negative factors are not counted while you have Autopilot engaged. For example, if someone cuts you off on the highway while Autopilot is engaged, you will not get negative scores for unsafe following or hard braking. The flip side is that “safe” turning, braking and following is also not counted toward the total while in Autopilot. So if you’ve already got a non-zero score for any of these factors, you’ll need to take the wheel yourself in order to lower those scores.
So now that we know the rules, here are three tips to help keep your Safety Score up (and one “Secret Weapon” to use when all else fails):
1.) Avoid Forced Autopilot Disengagement: this one is simple – don’t force the car to turn off Autopilot. Pay attention when using Autopilot and always keep your hands on the wheel. If you’re like me and don’t apply much force with your hands on the wheel, then pay attention to the screen warnings and be prepared to apply some tension to the wheel or use the steering wheel control dials to let the car know you’re still awake and aware. If you do get dinged for Autopilot disengagement, don’t get discouraged. Just get out there and keep driving. Continued safe driving will lower the score over time. Also, the Safety Score is a rolling 30-day window so eventually the penalty will go away entirely.
2.) Drive Manually When You Need to Improve Your Scores. If you’ve got some points against you for hard braking, then get out there, drive around your neighborhood and begin your stops with extra distance so you will have time to come to a gradual stop. It helps to do this when traffic is light. I’ve noticed that I sometimes get dinged for “hard braking” just by using Regen in its “standard” setting (not applying brakes at all). This is particularly true when slowing down on an uphill incline. So you may need to feather the accelerator pedal slightly in order to slow down at the ideal rate. The same applies for “aggressive turning” – the more turns you make that are considered “safe” the lower your penalty. The same is true for “Unsafe Following.”
If possible, try to counteract negative scores on the same day that you’ve had the penalties. Your overall Safety Score is calculated using your daily score multiplied by miles driven that day, with those daily mileage-weighted scores then aggregated and averaged out over the total number of miles driven. So ending the day with a score of 99 with 100 miles driven is much better than ending the day with a score of 96 with 50 miles driven.
These are the current “sweet spots” that will help you improve or maintain your Safety Score in the three main areas:
- Hard Braking: keep your braking between 0.1g (slowing down 2.2 mph per second) and 0.3g (slowing down at 6.7 mph per second) to avoid the hard braking penalty
- Aggressive Turning: keep your turns between 0.2g and 0.4g (lateral acceleration of 4.5 mph/second to 8.9 mph/second)
- Unsafe Following (only measured at or above 50 MPH): generally speaking, keep the distance between your car and the one in front of you over 3 car lengths but less than 7 car lengths. Of course, the actual safe distance depends on how fast you’re travelling. Tesla currently states that the sweet spot for “headway” (time needed to come to a complete stop) when calculating the score is over 1 second of reaction time, but under 3 seconds. To me this is a little counterintuitive as I would prefer to follow with at least 4-5 seconds of headway, but if you are too far behind the car in front of you, it may not count as “following” at all and this won’t help lower your “unsafe following” score. When in doubt (particularly in inclement weather), just leave extra space – better to avoid an accident than to worry about some arbitrary number on a screen. Also, “unsafe following” is much less important to your overall score than “hard braking” due to the current weighting system.
3.) When Things Get Dicey, Engage Autopilot. Keep in mind that you need to be driving the car manually to get credit for positive behaviors. But even the safest drivers can be somewhat at the mercy of the many aggressive and unsafe drivers who share our roads. Someone may cut you off or cross in front of you without properly yielding right of way. And this could impact your scores for safe following, hard braking or forward collision warning. So if the road you’re on gets busy and you suspect that impatient drivers around you are going to cut you off, then simply press down on the stalk twice to engage Autopilot. If you do get cut off while in Autopilot, the car will not penalize your rating even if the car itself has to apply “hard braking” or “unsafe following.” Then when traffic eases up (or the idiot driver has disappeared over the horizon), tap up on the stalk to disengage Autopilot and resume manual control.
The good news is that mileage driven on Autopilot does count toward the overall Safety Score’s “mileage weighted average.” So if you do manage to get a high score on a very long drive – even if you are mostly in Autopilot – this can help to quickly bring your overall score up. Also, miles driven on Autopilot count toward the “Front Collision Warning” score as that is based on how many FCWs you get per 1,000 miles driven.
The Secret Weapon? When All Else Fails, Reboot!
Even the most vigilant drivers are sometimes at the mercy of others. A pedestrian may run in front of your car, an oncoming driver may swerve into your lane, someone may run through a red light. Any of these events could trigger a penalty for hard braking, aggressive turning, front collision warning – even all three. If this happens to you, then a simple soft reboot may prevent the trip from being stored and the “unsafe behavior” from impacting your score. I was recently driving in New York City, had to cross over the yellow line in order to drive around one of many double-parked cars and got a collision avoidance warning from an oncoming vehicle. I performed a soft reboot (held the left and right steering wheel buttons for a few seconds) before putting the car in park at the end of my trip. And sure enough, the trip – and the warning – was not recorded.
I’m not sure if this is a bug or a feature. And it’s possible that it won’t always work. But if you’ve been doing your best to drive your best and you still get dinged due to unforeseen circumstances, it’s certainly worth a shot.
Have your own tips on how to keep your Safety Score up? Let us know in the comments.
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