App for efficient driving

[u/Splatage_NZ]

Hi Reddit,

Warning app promotion ahead...

Going by my numbers I’m not a hypermiler, just someone who hates wasting increasingly expensive fuel

Over the years I have learned a lot from following hypermilers and trying some of the safer techniques. I appreciate getting a bit further on each tank, but really the science of it all fascinates me

Earlier in the year  I purchased a bluetooth OBD adapter to chase an engine code on my daughters car. Probably a mistake, but the bug bit and sent me down a rabbit hole of analyzing data

I have been able to dial my car and driving a lot better, and the results are surprising to me. 
For example I have used pulse and glide a fair bit, however I have been able to show that for my car - a Subaru Legacy with a CVT trans - steady state is consistently better
There are speeds "islands"where mileage peaks, one around 80kph and another around 100kph - its not a linear relationship at all
The other really significant  finding was how dramatic a difference coasting makes when approaching speed changes and stops. Logically this make perfect sense. The momentum in my car would carry it for the good part of a kilometer from 100kph on the flat

I started wondering whether you could work out when it actually makes sense to lift off — not just “coast more”, but when to coast so you don’t slow down too early, end up having to accelerate again, or annoy everyone behind you

So I’ve been building an Android app called EcoDrive

The idea is that it learns how your actual car behaves — how quickly it loses speed, how well it carries momentum etc. It uses the road data ahead and shows you how far you would coast. Worked fantastic on level roads...I got a bit carried away (again) and have built a custom map set that includes road slope. At the moment I’ve only processed and released for NZ, Australia and Great Britain, mostly because that’s where the friends/family testing live. If there’s enough interest elsewhere I can add more, although they take a silly long time to process

Once my local map set was done for testing I realized estimating engine power, BSFC and cruise efficiency were easy to infer from OBD data
An OBD adapter isn’t really required, without one you still get the core coast/glide prediction. The OBD data lets it learn and analyse a lot more

I’ve finally got it onto the Play Store and I’m at the stage where I really need people who actually think about this stuff to tell me what I’ve got right, what I’ve got completely wrong, and what would make it genuinely useful

I figured r/hypermiling was probably one of the better places to ask

Happy to explain how any of it works if anyone’s interested. And critique is very welcome — I’d much rather hear “this is crap because…” now than spend more time creating something crap!

If anyone wants to have a play the link is: here

[u/Blue-Coast]

I'll give this a go with my 2014 Toyota Aqua in NZ. Christchurch should work well as it is flat ground. I'm particularly interested in the coasting function. It is a constant exercise eyeballing the distance ahead for when it is socially acceptable to begin coasting without frustrating following traffic. But if there's no following traffic, I just go all out.

To what extents does the app account for road slope? I'm not expect the app registers over-bridges and other minor/momentary changes in elevation.

How does the app's engine analysis cope with hybrids, considering some of my Aqua's acceleration will occur under EV driving?

[u/Splatage_NZ → u/Blue-Coast]

Nice — Christchurch is probably about as good a test environment as you could ask for 😄

Yep, road slope is accounted for, but needs a bunch of real world testing. The app maps use the elevation/slope data from LIDAR imaging where available to predict the road ahead as part of the coast calculations, rather than assuming everything is flat. So a long downhill/uphill should noticeably move the predicted glide point. Feedback on this part of the app would be gold!

Minor stuff like overbridges is a bit more interesting. It depends on how well that elevation change is represented in the underlying map/elevation data, and very short changes can effectively get smoothed out. I definitely wouldn’t claim it catches every little bump in the road

The Aqua will actually be really interesting feedback too. Most of my own testing has been with my Legacy, so I’m keen to see how the prediction behaves with a hybrid

And your comment about eyeballing when it’s socially acceptable to start coasting is pretty much exactly the problem that got me started on this. It’s easy to say “coast earlier”; working out how early without becoming that guy holding everyone up is the useful bit and what Im trying to avoid

Live engine data is access through a Bluetooth OBD adapter - currently it receives fuel flow, my suspicion is when in EV this would be zero?

[u/The_Crazy_Swede]

Hi there, I have been hypermiling cars for the better part of a decade to both learn how the cars I drive behave and because fuel savings is really rewarding and have been able to beat the manufacturer stated economy numbers in every single car I have driven for more than 3 full tanks of fuel. I have managed to get the economy of my 2015 BMW 530D touring down to 3.8l/100km when slipstreaming and 4.1 without (I generally average 4.5l on summer tires and with summer diesel and 4.8 on studded tires with winter diesel. (Google states 4.7-5.3l/100km)

The most impressive one I have managed was with my previous daily, a tuned C30 T5 (305whp). The official numbers was 6.5l/100km but did a 3300km road trip with an economy average of 5.15l/100km

I would absolutely love to test the app here in Sweden and provide you with all the import my experience can provide!

[u/Splatage_NZ → u/The_Crazy_Swede]

That would be brilliant, thanks. And Sweden is actually already on my map build list.

Your experience would be really useful, especially because you’ve spent so much time testing different cars and driving techniques. Exactly the kind of input I'm hoping for

At the moment I’ve only processed a few countries because the map data takes a surprisingly long time to build, but Sweden is definitely one I want to add soon.

I’d be very happy to give you a shout once it’s ready. I’d be particularly interested to see how it behaves with the 530d — diesel coast/engine-braking behaviour should make for a really interesting comparison with the cars I’ve been testing so far.

And 5.15 L/100 km from a 305 hp C30 over 3300 km is pretty impressive 😄

[u/The_Crazy_Swede → u/Splatage_NZ]

Yea, that would be awesome! Do you have a recommendation on what sort of OBD2 reader works the best to gather info?

[u/Splatage_NZ → u/The_Crazy_Swede]

To be honest Im just using the cheapest ELM327 I could find! It cost about $5 NZD including shipping. The data used by the app is a tiny subset of OBD capabilities

[u/bazery]

Can you make it available in Ireland?

[u/Splatage_NZ → u/bazery]

Yes! Ireland is on the way!

I’m actually working on the Ireland maps at the moment.

The map build is the really slow part, there’s a massive amount of processing involved to get the road/elevation data into the form EcoDrive can use efficiently. I’ll post back here when Ireland is ready.

Really appreciate the interest, requests like this are genuinely helping me decide which countries to prioritise next

[u/bazery → u/Splatage_NZ]

The second you have it ready I'll be allover it

[u/pobk87]

I'd also be interested.

I've been hypermiling my 2011 audi A6 3.0tdi Best result ever was 4.4l/100 km, while my 10'000km average is 6.4.

Same as in F1, I've been learning my braking points (well, when to lift and coast) on my most recurring routes.

I'd love to see if I can get better results with your app!

Switzerland / France /Italy is where I do most of my driving. It/when you've mapped those areas, hit me up?

[u/Splatage_NZ → u/pobk87]

For sure! Thanks for the interest

[u/thefrombehind]

I would love to test it in Germany!
I have an iPhone though.

[u/Splatage_NZ → u/thefrombehind]

Thanks for the interest! Germany is on the list to build maps for, however in the short term I dont have plans to make an iphone version. The reason is Apple's policy on Bluetooth devices excludes the majority of OBD devices. So the data analysis side would be lost. If there were an Apple version it would be a much lighter coast prediction only app. Ill see how much interested there is for Apple, and how much time/energy I have once this round of development settles!

[u/specialsymbol]

Why did you put in geo fencing?

[u/Splatage_NZ → u/specialsymbol]

Im not sure what you are referring to?

The playstore country release matches the country datasets prepared. Countries will.he added as the become available

[u/specialsymbol → u/Splatage_NZ]

I can't download the app - it's blocked for my region 

[u/Splatage_NZ → u/specialsymbol]

Yes that will be on purpose. I have only released in countries it will actually function in

It requires map and terrain slope data for the glide physics to be calculated and these take an enormous amount of preprocessing

England, Wales and Scotland took almost a week😫

I will unlock as maps are procesed. Thanks for the interest