The hazard of these cars is surprise: They can be operated with dynamics that surrounding traffic do not or cannot expect.
Speed differentials are hazardous because of limits of human attention.
Consider the simple case of an urban crosswalk: The rate of vehicles vs. pedestrians has an attention hazard for both: there's a speed beyond which the pedestrian can not safely judge a crossing because the vehicle will pass in a duration shorter than the attention span of the ped. Similarly there's a speed at which the operator can not react to appearance of ped.
Simple V differences are a well known hazard of surprise. EVs create another hazard which arise from relatively high delta-V dynamics. The vehicles can accelerate at surprising rates and therefore appear in places that operators don't expect them to be. For example, merging requires anticipation that the surveyed gap will be maintained during the crossing. Surrounding vehicles operating with disproportionate V or high dV upset the balance of the gap.
Surprise can have cascading effects, where surprised operators lose attention which in turn causes further hazards.
We might suspect that given the surprising power of EVs, their saving grace is that their operation in urban traffic tends towards operator passivity. But this tendency obviates power: the proper power level is that which permits the vehicle to operate fluidly with traffic.
Regardless of attention spans for operators, the simple mechanical comfort of occupants places very low limits on vehicle dynamics.
Vehicle power was already becoming well balanced before EVs, and EV development should be further refining the balance in favor of safety, comfort, efficiency, and wear.
But there's always an edge of fascination with performance limits.
>Mass is still the enemy here, and EVs typically have lots of it. Factor in bigger brakes and wheels, and the result is an increase in unsprung mass. That puts the springs and dampers under more pressure, which results in an increased amount of energy that needs to be managed, and unwanted oscillations when a car hits a pothole, for example.
This is straight up delusional.
The cars increased weight increases grip, making it safer in the corners and less prone to oscillate. Potholes are less disturbing at higher unsprung masses and faster speeds, as the wheel dips into the hole less.
They are totally mangling car physics to make what point exactly? Cars accelerate too fast?
Sorry but you're not correct either. The mass makes the car stop slower, makes it corner worse. 100% of the time. Weight is the enemy of performance. You don't see race cars adding weight. Less weight makes everything function better.
Potholes are less disturbing, that is true, but that's because the car is so heavy it won't dip into the hole as quickly. It's still harder in your whole suspension.
We had big huge heavy cars in the 60s and 70s. They rode great, but nobody ever said they handled well or were fast.
>The mass makes the car stop slower, makes it corner worse. 100% of the time.
Adding weight increases stopping distance under most circumstances. Who said anything about that? Corning "worse" is a dumb metric, this is not about performance in a sports car, but about the characteristics of a consumer vehicle. They are designed for comfort, not to corner fast, obviously.
>Less weight makes everything function better.
Completely false. A heavy car is generally more comfortable.
Why you are brining up sports car is a mystery to me. Every single sports car would make a horrible and painful 500 mile drive. Obviously the engineering tradeoffs for speed on a track and a desirable consumer car are radically different. Sports car reduce weight for track performance, applying the same principle to a family SUV would be lunacy.
>Potholes are less disturbing, that is true, but that's because the car is so heavy it won't dip into the hole as quickly. It's still harder in your whole suspension.
Wrong explanation. The weight of the unsprung mass makes the difference. Higher unsprung mass means moving slower into the pothole.
>They rode great, but nobody ever said they handled well or were fast.
The hazard of these cars is surprise: They can be operated with dynamics that surrounding traffic do not or cannot expect.
Speed differentials are hazardous because of limits of human attention.
Consider the simple case of an urban crosswalk: The rate of vehicles vs. pedestrians has an attention hazard for both: there's a speed beyond which the pedestrian can not safely judge a crossing because the vehicle will pass in a duration shorter than the attention span of the ped. Similarly there's a speed at which the operator can not react to appearance of ped.
Simple V differences are a well known hazard of surprise. EVs create another hazard which arise from relatively high delta-V dynamics. The vehicles can accelerate at surprising rates and therefore appear in places that operators don't expect them to be. For example, merging requires anticipation that the surveyed gap will be maintained during the crossing. Surrounding vehicles operating with disproportionate V or high dV upset the balance of the gap.
Surprise can have cascading effects, where surprised operators lose attention which in turn causes further hazards.
We might suspect that given the surprising power of EVs, their saving grace is that their operation in urban traffic tends towards operator passivity. But this tendency obviates power: the proper power level is that which permits the vehicle to operate fluidly with traffic.
Regardless of attention spans for operators, the simple mechanical comfort of occupants places very low limits on vehicle dynamics.
Vehicle power was already becoming well balanced before EVs, and EV development should be further refining the balance in favor of safety, comfort, efficiency, and wear.
But there's always an edge of fascination with performance limits.
> To which WIRED can only reply, who in their right mind wants to go that fast?
To which I can only reply: seriously, who asked you to decide what i want or do not want?
>Mass is still the enemy here, and EVs typically have lots of it. Factor in bigger brakes and wheels, and the result is an increase in unsprung mass. That puts the springs and dampers under more pressure, which results in an increased amount of energy that needs to be managed, and unwanted oscillations when a car hits a pothole, for example.
This is straight up delusional.
The cars increased weight increases grip, making it safer in the corners and less prone to oscillate. Potholes are less disturbing at higher unsprung masses and faster speeds, as the wheel dips into the hole less.
They are totally mangling car physics to make what point exactly? Cars accelerate too fast?
Sorry but you're not correct either. The mass makes the car stop slower, makes it corner worse. 100% of the time. Weight is the enemy of performance. You don't see race cars adding weight. Less weight makes everything function better.
Potholes are less disturbing, that is true, but that's because the car is so heavy it won't dip into the hole as quickly. It's still harder in your whole suspension.
We had big huge heavy cars in the 60s and 70s. They rode great, but nobody ever said they handled well or were fast.
>The mass makes the car stop slower, makes it corner worse. 100% of the time.
Adding weight increases stopping distance under most circumstances. Who said anything about that? Corning "worse" is a dumb metric, this is not about performance in a sports car, but about the characteristics of a consumer vehicle. They are designed for comfort, not to corner fast, obviously.
>Less weight makes everything function better.
Completely false. A heavy car is generally more comfortable.
Why you are brining up sports car is a mystery to me. Every single sports car would make a horrible and painful 500 mile drive. Obviously the engineering tradeoffs for speed on a track and a desirable consumer car are radically different. Sports car reduce weight for track performance, applying the same principle to a family SUV would be lunacy.
>Potholes are less disturbing, that is true, but that's because the car is so heavy it won't dip into the hole as quickly. It's still harder in your whole suspension.
Wrong explanation. The weight of the unsprung mass makes the difference. Higher unsprung mass means moving slower into the pothole.
>They rode great, but nobody ever said they handled well or were fast.
Sure. Engineering tradeoff.