[bbv]

I am planning to go for XUV 700 AX7L and have few questions for the people who have been using ADAS often and in different conditions.

1) How does ACC copes with the speed breakers? Does the vehicle slow down detecting these bumps or the driver has to take over?
(Although not many speed-breakers are there on highways, nevertheless there still are, at least in southern states)

2) I read earlier about traffic Jam assist, what is this? The understanding I got till now was that ACC can't be activated until a certain speed is reached (e.g. 60 kmph), but in bumper-to-bumper traffic, this is obviously unachievable.

3) With Lane Keep assist, how does the car reacts on bends or turns? Does it slow down sufficiently or a driver's interaction is needed? In this context, is ACC needed to be switched ON for LKA to be functional?

[saket77]

Originally Posted by bbv

1) How does ACC copes with the speed breakers? Does the vehicle slow down detecting these bumps or the driver has to take over?
(Although not many speed-breakers are there on highways, nevertheless there still are, at least in southern states)

2) I read earlier about traffic Jam assist, what is this? The understanding I got till now was that ACC can't be activated until a certain speed is reached (e.g. 60 kmph), but in bumper-to-bumper traffic, this is obviously unachievable.

3) With Lane Keep assist, how does the car reacts on bends or turns? Does it slow down sufficiently or a driver's interaction is needed? In this context, is ACC needed to be switched ON for LKA to be functional?

1. ADAS detects only pedestrians, bicyclists & vehicles. So, speed breakers, trees, pillars etc aren't responded to; by ADAS.

2. No idea. Mahindra owners may chip in please.

3. Car will not slow down with lane keep assist. The car will turn on the curve with slight automatic steering torque. The driver must keep their hands on steering. Do not assume this to be a substitute to driver's input. It is just to reduce the effort. The driver must be fully alert.

Trust this helps 66%

[Beemer1077]

The ADAS is extremely ineffective on the roads in India, with a few exceptions -

1. Many of the roads do not have proper lane markings. This means that the lane departure warnings will not work effectively.

2. The ADAS does not take into consideration sudden entry of bikers, stray animals like cattle or dogs.

3. The ADAS is only effective on expressways and those highways where there is a maximum and minimum(if present) speed limit.

[bbv]

Originally Posted by saket77

1. ADAS detects only pedestrians, bicyclists & vehicles. So, speed breakers, trees, pillars etc aren't responded to; by ADAS.

2. No idea. Mahindra owners may chip in please.

3. Car will not slow down with lane keep assist. The car will turn on the curve with slight automatic steering torque. The driver must keep their hands on steering. Do not assume this to be a substitute to driver's input. It is just to reduce the effort. The driver must be fully alert.

Trust this helps 66%

Thanks for your response, yes it certainly helps .

So, as I understand, there needs to be a manual intervention in the following cases:
- During ACC, whenever there is an object/situation not detected by ADAS viz. animals, speed breakers.
- With LKA, whenever there is not a straight stretch of road. I wonder, how would it react, if it would still steer to keep the vehicle in lane, irrespective of whether driver slows down or not, because this could lead to roll-over? (it is another thing that it will anyways be quite dangerous even with LKA, if driver doesn't act)

Let me clarify that these questions/doubts are not to encourage sleep-driving, but just to understand the scope of ADAS better.

[audioholic]

Originally Posted by bbv

Thanks for your response, yes it certainly helps :.
- With LKA, whenever there is not a straight stretch of road. I wonder, how would it react, if it would still steer to keep the vehicle in lane, irrespective of whether driver slows down or not, because this could lead to roll-over? (it is another thing that it will anyways be quite dangerous even with LKA, if driver doesn't act).

Lane keeping assist in general is designed to keep the vehicle within lane center with a slight possible deviation due to various factors. In straight roads, the system will work perfectly. In curvy roads, the system can work perfectly but there are external factors that will hinder its performance. As the curvature increases, the steering rack force needed to maintain this curvature increases. The LKA being an L2 Assist feature has limitations in terms of how much rack force it can apply to keep the vehicle centered. If this reaches the limit, the system cannot apply more force and will hold at the limit.

Why this limit? The rack force limit is meant to enable any driver to override any unwanted intervention from the system and still be able to counter the system applied force. Imagine the LKA detects fake lanes and applies a lot of rack force, the driver won’t be able to overcome it and will lead to disastrous consequences.

Rack force limit can be reached due to different reasons - One the curve being too sharp and sudden, or the vehicle already drifting away to one side due to driver action or non action or the vehicle being too fast in a corner. In these cases, most LKA systems give up or dont react. Thats the reason in most cars with LKA, it takes getting used to its behaviour and initially might feel annoying. But once we get a sense of the limits of the system, it will get predictable. Those who want to understand this system better can try keeping a light grip on the steering and letting the system do its bit and be ready to intervene if needed.