Lobby Honda for Assist Logic Change?

[hansonclan]

First, thanks to all who have posted fuel saving tips for the HCHII - great way to learn quickly without too much trial and error.

A common theme seems to be to minimize assist and use the batteries mainly for accessories to get the best FE. I tend to agree, although I only have two months' experience with my car. We also know it is nearly impossible to avoid assist when accelerating when the SOC is above a certain level.

I would like to have assist for an emergency situation, like to avoid a collision - I want all available thrust. I have gathered, although I couldn't cite specific posts, that assist affinity is controlled by software and could possibly be changed. Maybe begin assist above a certain throttle position, like 50%?

I think it was MSantos who outlined the role of assist in keeping the batteries cooler for longer life. Perhaps there are other engineering reasons as well. I'm all for longer battery life, but I wonder if Honda wouldn't consider taking another look at the assist affinity logic if thousands of HCHII owners wanted it? Without undue impact on battery life, of course.

Comments?

[msantos]

Hi Hansonclan;

Indeed. We have been pestering Honda on that account for the better part of the last two years. Its been a bit of a long road because it took a lot of time to make our way though the "people chain" and frankly that was the most frustrating part of it all.

Anyhow, they finally granted me an audience earlier this year during two distinct opportunities to make my case (the first looked more like a "get to know you" session). All in all, it was a very good opportunity to speak to the folks that really knew what I was talking about... and as always, we can really make a lot of progress when all the people in the room are engineers.
But while they were very receptive, it still remains to be seen whether they'll give us the flexibility we asked for. I went there with a pretty long list and soft control of the assist affinity was definitely one of the top items.

Cheers;

MSantos

[hunter44102]

Is there a full list of proposed 'Assist' changes somewhere on this forum?

Doesn't constant Assist usage reduce the wear on the 1.3 liter engine?

I'm all for improvements but not if it will reduce engine life!

[xcel]

Hi Hunter:

___Engine wear? Not even close! Increased pack longevity and FE, you bet!

___Good Luck

___Wayne

[hansonclan]

But while they were very receptive, it still remains to be seen whether they'll give us the flexibility we asked for.

Hi MSantos,

I had read the affinity discussion in the thread that is now a sticky. I was not aware that you had discussed this assist logic question with Honda engineers - good for you.

I presume from your statement above that you still believe that the FE benefit from an adjustment of the assist affinity logic would outweigh the potential downside, or did the Honda folks convince you otherwise? Were you armed with the support of your fellow HCHII owners when you met with them?

I would like to understand all the engineering that went into the car, in order that I don't advocate something that might impact battery or drivetrain reliability. I don't know if it's possible for me to know enough - don't think I'll ever be invited to talk to Honda engineers about it! All I know is that I see assist when I don't think I need it, often followed by forced regen later in my commute. I'm happy with my mileage (~54mpg), but would like to do even better.

I apologize if this has been covered in an earlier thread.

[msantos]

Hi Hansonclan;

As it is typical in these matters, I did most of the talking and nothing was promised to me. In the end they knew I had done my homework and also paid my technical admission price in more ways than one before I would have been given a minute of their attention.

Anyway, there aren't that many people in North America that have very detailed knowledge of the platform but we can definitely discuss the various system details without any concerns for any major missteps. The fundamental requirement is that we do so in the context of proper documentation and adequate technical support. So far, I have been extremely privileged to not only have access to the required info but also able to exercise some very "benevolent and generous" support channels. Let us just say, that one's background and personal hooks can help a little now and then.

So by all means, feel free to get detailed and technical and we'll see how far we can take this. If it gets really interesting, I'll even bring a few "surprise people" into the chat.

Hunter:
As Wayne said, I would not worry much about the reliability issues of inhibiting the assist. The key here is that the assist avoidance we're seeking is not a total elimination of it but rather an opportunity to avoid it whenever the conditions are suitable (and that constitutes more than 90% of the scenarios we encounter). In any case, their affinity coding is oblivious to the opportunities for great FE and they know it.



Cheers;

MSantos

[hansonclan]

So by all means, feel free to get detailed and technical and we'll see how far we can take this. If it gets really interesting, I'll even bring a few "surprise people" into the chat.

MSantos - I didn't explain myself very well. I don't have the technical expertise to get detailed and technical. I just want to be able to get the max FE out of my HCHII, and if I see something that doesn't seem intuitive, I start wondering why that is and if it can be changed. The assist logic is one example. I was really just wondering if Honda might take another look at their logic if enough consumers wanted them to. At the same time, I wouldn't want to pressure them to do something that might impact reliability in a meaningful way. I think you answered my question though when you responded to Hunter:

Hunter: As Wayne said, I would not worry much about the reliability issues of inhibiting the assist. The key here is that the assist avoidance we're seeking is not a total elimination of it but rather an opportunity to avoid it whenever the conditions are suitable (and that constitutes more than 90% of the scenarios we encounter). In any case, their affinity coding is oblivious to the opportunities for great FE and they know it.

That is exactly what I'm looking for. My original thought was that if thousands of HCHII owners petitioned Honda, perhaps through a poll or something on this site, they would examine the question you posed. It sounds like they are doing just that. Let's hope they come up with a satisfactory solution that can be retrofitted via software to the HCHII.

Xcel - Thanks for a great site - tops of those I've seen in terms of usable knowledge. I hope you have other good subject matter experts like MSantos for other vehicles.

[kristian]

I would be stoked to see a revision to this logic! There are admittedly a lot of times when the assist is important (it got me up a really steep dirt road last weekend at 10,600 feet), but I find myself trying to cancel it out a lot more than I find it helpful. If they were able to inhibit the affinity (more) below a certain throttle position, it would be the best of both worlds. I'm sure they erred on the side of "driveability*" for the sake of comparison to the gas Civic, but it would be nice to be able to make a concious descision regarding the performance--similar to Subaru's "S-Drive" or the HiHy's econ mode. If the new "Insight" has an ability like this, it would be a serious reason to trade.

*regarding the "driveability": in all honesty, if they hadn't have defaulted to a liberal assist managment, I might have been a little scared off this car. Obviously, I know better now, but at the time I was used to a different level of power and if the HCH had been a whole lot less, I might not have taken the leap.

[hunter44102]

The best way they could solve this is to install a button that enables "Smart Assist" logic or something like that. This way they can leave the normal logic enabled for most people but give others the option of not having too much automatic assist.

[hansonclan]

I got my new Honda owner's survey via email today. Here's my reply to the question about the most useful feature that I would add to my new Honda:


"Less motor assist affinity. I find it nearly impossible to avoid motor assist during acceleration. Then later in my commute I might find myself having a forced recharge, with the resultant decrease in fuel economy.

I want to use the battery for overhead (electrical systems, A/C), and recharge it with regenerative braking. I think that's the most efficient use of this "mild hybrid" system. The current program's eagerness to provide motor assist defeats this strategy.

I want assist available when I need extra power, but I don't want it under normal circumstances. It seems one solution might be to inhibit assist below a certain throttle position, like 25%.

If there are other reasons for the high assist affinity, like drivetrain or battery reliability, that's understandable. But I would like to know if that's the case."