Road Sign Assist

[Shalom C]

My 2019 Prius now has RSA instead of the speed limits on the sat nav. Toyota have informed me that they have no intension of reversing this decision at present. Why replace a system that works with one that doesn't? RSA misreads speed limit signs on the roads and sometimes doesn't see them at all. The function is not fit for purpose. 

[Mick F]

I was loaned a courtesy Yaris when our Yaris was in for a service etc.

It was a late model and had satnav as well as speed limit sign recognition.

The satnav sort of knew the speed limits but the camera system often missed them out.  It was belt and braces, and neither of them were perfect ............... whereas I am perfect and I have eyes and a brain and I know what the speed limits are! 😀

Mick.

[Shalom C]

 I have come to the conclusion that it's better to switch it off and go back to keeping eyes open and being alert. Boringly old fashioned but there you go!

[PeteB]

I wonder if the 2019 version of the Prius is still using version 1 of the Safety Sense package?  My last car, a 2016 Prius, had that and I agree, it was useless.

My new RAV4 has version 2, with some useful improvements in most of the Safety Sense features, including RSA.  It's still not 100%, but my experience has been that it's right at least 95% of the time, and when it briefly gets it wrong (for example, when passing rather than taking a 20 mph exit on a mini roundabout, it usually corrects itself quite quickly.  This is because, unlike Safety Sense 1 which only used the windscreen camera, Version 2 combines this with the SatNav database and when there's a discrepancy, it seems to use some sort of logic to determine which is more likely to be right.  I'm happy to leave it active on my current car.

On top of that, when it is right, it can be used to rapidly set the Adaptive Cruise Control set speed.  For example, if the current limit and ACC setting is 40 mph, and you pass a 60 mph sign, as long as the displayed speed limit is correct, pressing and holding + will put the set speed straight to 60.

The ACC is also improved in that the set speed can now be as low as 18 mph (28 in the 2016 Prius), making it really useful in 20 limit zones.  Also, Resume now works at any speed, including stationary, so that as traffic starts to move or traffic lights change if these's nothing in front, tapping the accelerator or selecting Resume again make the car set off without any further use of the accelerator.

[altocumulus]

I found the RSA was accurate maybe 80% of the time on my two RAV4s, whilst on my phv it's accurate 60% - perhaps due to height of camera on the cars?

Switched off very quickly!

Satnav still displays, latest build.

[PeteB]

2 hours ago, altocumulus said:

I found the RSA was accurate maybe 80% of the time on my two RAV4s, whilst on my phv it's accurate 60% - perhaps due to height of camera on the cars?

Switched off very quickly!

Satnav still displays, latest build.

What you say makes me think the post face-lift Prius PHEV (and therefore, probably, the Prius ordinaire too) still have version 1 of the Safety Sense features, whereas the completely newly designed 2019 model onwards RAV4 and Corolla have version 2.

Out of interest, what is the lowest speed your Adaptive Cruise Control can be set to maintain (subject to traffic in front)?  Whilst not conclusive, if it's around 28 mph rather than 18, that would add a little more weight to my belief it's SS version 1.

[Shalom C]

Hello Pete. I've checked about the versions of the safety sense and the powers that be say it's version 2 on the 2019 Prius. I'm also wondering whether the difference in efficiency or lack of it is down to the height of the vehicle. If this is the case, it's of no use in a Prius that has had it's speed limits greyed out as an option on the sat nav.

[Catlover]

Can’t see the logic in saying height of car will stop RSA from working effectively. The camera lens simply need to point at the height a road sign would be at a certain distance for it to read. Just my thoughts.

[altocumulus]

3 minutes ago, Catlover said:

Can’t see the logic in saying height of car will stop RSA from working effectively. The camera lens simply need to point at the height a road sign would be at a certain distance for it to read. Just my thoughts.

I agree Joe, but how to explain why the RAV4 does better than the Prius (in my experience).

Mind I've often wondered, with all these TSS features, as to why they don't incorporate an accident Dashcam!

[Shalom C]

I have no idea why the RSA in the Prius is useless. Just offering my thoughts. 

[Catlover]

I understand, Shalom, it’s bugs me too when nothing seems logical and can’t get an athoritiv answer.

[PeteB]

1 hour ago, altocumulus said:

...I've often wondered, with all these TSS features, as to why they don't incorporate an accident dashcam!

Me too, and I've made the same comment in a number of other threads.

Dashcams started appearing nearly 20 years ago, and I was sure by 2010 manufacturers would have stated offering built in ones.  They could incorporate speed info, plus details of what lights are on, signals, horn use etc.

I wonder what type of "black boxes" new cars in Europe and the UK will be required to have from 2022 - a camera based system would make a lot of sense.

[Shalom C]

1 hour ago, Catlover said:

I understand, Shalom, it’s bugs me too when nothing seems logical and can’t get an athoritiv answer.

Absolutely right Joe. My wife has told me she wishes she still had her little Aygo. That had speed limits on the sat nav!

[Ten Ninety]

2 hours ago, altocumulus said:

Mind I've often wondered, with all these TSS features, as to why they don't incorporate an accident dashcam!

Actually, they do (as long as PCSS is on). It's just one that's only accessible by the manufacturer.

[PeteB]

10 minutes ago, Ten Ninety said:

Actually, they do (as long as PCSS is on). It's just one that's only accessible by the manufacturer.

Although pictures only seem to be recorded while the PCSS is doing emergency braking if I am reading this correctly.

[altocumulus]

Interesting. So if the driver doesn't brake, but comes to a stop after an impact......

[Seamaster73]

Couldn’t agree more about that road sign business. Absolutely hopeless. 

What I can’t figure out is why it thinks whole stretches of A road in south west Scotland are 40mph limited when there is absolutely no signage to that effect.

[PeteB]

20 minutes ago, Seamaster73 said:

...What I can’t figure out is why it thinks whole stretches of A road in south west Scotland are 40mph limited when there is absolutely no signage to that effect.

If your latest model Prius does have Safety Sense version 2 like my RAV4, then one possible reason is that it uses both the camera on the front screen and the speed limit data in the SatNav database (even though it no longer displays speed limits on the SatNav screens), and somehow tires to work out which is more likely to be right if there's a discrepancy - which can still give the wrong answer.

[Harters]

On 11/16/2019 at 9:34 PM, PeteB said:

... Also, Resume now works at any speed, including stationary, so that as traffic starts to move or traffic lights change if these's nothing in front, tapping the accelerator or selecting Resume again make the car set off without any further use of the accelerator.

Pete, this is how my 2017 Prius works now (the including stationary part), I use it all the time in queueing traffic on my journey home.  Personally I can make a smoother take off from stationary myself, the ACC tends to want to take off quicker than I would.

[ian rooke]

Hi I have had the road sign recognition show signs which do not exist as in end of 130 mph zone also when it shows two signs it has seen they are both the same, it misses easily visible signs, it is right less than 60%of the time it is supposed to be a drivers aid it just causes confusion 

 

[PeteB]

12 hours ago, Harters said:

...Personally I can make a smoother take off from stationary myself, the ACC tends to want to take off quicker than I would.

I'm guessing you're in NORMAL or SPORT mode?

I use ECO all the time and it's really quite smooth and sedate.  If I need a bit more urgency, e.g. for pulling into a lane of faster traffic, I switch to one of the other modes, which gives a significant boost at each extra level.

[Harters]

7 minutes ago, PeteB said:

I'm guessing you're in NORMAL or SPORT mode?

I use ECO all the time and it's really quite smooth and sedate.  If I need a bit more urgency, e.g. for pulling into a lane of faster traffic, I switch to one of the other modes, which gives a significant boost at each extra level.

Yes I always use normal 😀

[kithmo]

On 11/19/2019 at 8:20 AM, Harters said:

Pete, this is how my 2017 Prius works now (the including stationary part), I use it all the time in queueing traffic on my journey home.  Personally I can make a smoother take off from stationary myself, the ACC tends to want to take off quicker than I would.

My ACC seems to be the opposite, if I use resume, it seems not to want take off until there is a considerable gap with the car in front. This is embarrassing at traffic lights that change quick, as I feel like I'm holding up the traffic behind me. I usually use the gas pedal to overcome this. 

[Joseph D]

44 minutes ago, kithmo said:

My ACC seems to be the opposite, if I use resume, it seems not to want take off until there is a considerable gap with the car in front. This is embarrassing at traffic lights that change quick, as I feel like I'm holding up the traffic behind me. I usually use the gas pedal to overcome this. 

To what distance is the ACC set?

[kithmo]

5 hours ago, Joseph D said:

To what distance is the ACC set?

I've tried the 3 different distance settings but it does it on all of them (and in Normal mode). It also is slow to resume when the car in front turns off, it brakes/slows down enough (too much IMO) but the car in front has actually gone round the corner before it starts accelerating again.