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MIT team’s school-bus algorithm could save $5M and 1M bus miles

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Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#71

Post by pbhjpbhj »

hervature wrote: post #6
vineet wrote: post #2

I am glad that people are using algorithms to increase efficiency. But, this seems to only save $5M out of a $120M budget - I was expecting and am hoping for more. I feel like it would be an awesome project to dissect a large public institutions funding and to discuss ways that algorithms can help reduce costs without reducing the quality of service and agility of the organization. The site would not allow me to read…

For those that think that a 4% decrease (or equivalently a 5% increase) is not much, you should go ask your boss for a 5% raise and see what they think.

Isn't it more like tell your boss you'll take a pay cut, all it will cost is hiring your personal firm as efficiency consultants for £2M ... But look 5% reduction off your portion of the wage bill.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#72

Post by ztakeo »

dsfyu404ed wrote: post #57
ztakeo wrote: post #39

Earlier quoted context omitted.

Not sure if by "converting" you mean retrofitting old buses or replacing diesel buses with new electric buses. If it's the former definition, it's non-trivial from a safety and engineering standpoint to integrate a high-voltage, high-energy battery system into an old bus and expect to realize a decent ROI. Those old clunkers are not designed with an electric powertrain nor efficiency (i.e. they're heavy and have have…

Seriously? While aerodynamic teardrops are most efficient that means nothing if the up front cost is prohibitive. Also, efficiency and a box that's strong enough to appease the "think of the children" types are very much at odds with each other. For a bus with low mile requirements some boxes to hold batteries and a big DC motor where the engine goes would work fine. The "scaled up golf cart" architecture works well…

The upfront cost is no longer prohibitive with all-electric buses realizing savings in the form of reduced maintenance and fuel costs that exceed the initial investment discrepancy [1-2].

On your second point, a bus doesn't necessarily have to have a heavy steel frame for it to be safe. There are plenty of lighter weight (e.g. composite/carbon fiber) solutions which don't sacrifice safety.

Sure, if the mileage requirements are low then there's definitely a cost-effective retrofit solution. But if you're a company already building a full electric bus and investing a lot of R&D into the pack design anyway, then you could probably just sell battery solutions to school bus companies as another revenue stream. I'd wager, though, that the larger addressable market is customers looking for new electric buses for longer routes.

[1]http://www.columbia.edu/~ja3041/Electric%20Bus%20Analysis%20... [2]https://www.nrel.gov/docs/fy16osti/65274.pdf

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#73

Post by mulmen »

ztakeo wrote: post #39
towndrunk wrote: post #8

Kind of off topic but... why is no one converting school buses to electric? Seems like a perfect opportunity. Lots of space for batteries. High torque. Short runs in the morning and afternoon. Think of how many diesel school busses there are across just the USA every morning.

Not sure if by "converting" you mean retrofitting old buses or replacing diesel buses with new electric buses. If it's the former definition, it's non-trivial from a safety and engineering standpoint to integrate a high-voltage, high-energy battery system into an old bus and expect to realize a decent ROI. Those old clunkers are not designed with an electric powertrain nor efficiency (i.e. they're heavy and have have…

I would argue that efficiency is more important in a school bus than safety.

Buses are designed for many years of service with long-lived and easy to replace parts. On the safety front they are painted yellow and have some lights. That's pretty much it. They don't even have seat belts.

It looks to me like efficiency trumps safety in this case.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#74

Post by toomuchtodo »

mck- wrote: post #50
payne92 wrote: post #23

I worked with a startup years ago that did these kinds of optimizations (for deliveries). The logistics & transportation market in the US is about a TRILLION dollars -- small optimizations can make a HUGE impact. The challenge for practical implementations is that there are lots and lots and lots of optimization factors that are very hard to account for. Often, you don't even know what they are until you try to autom…

Despite gaps between technology and the real-world, there is still tremendous value to be had by technology, if you combined it with the real-world, i.e. humans. Routing algorithms can come up with extremely efficient routes, which can serve as a starting point for the human route planner to fix (to account for real-world knowledge). Consider the alternative where the human route planner starts from scratch.

UPS' automated routing system acts a partner with human drivers working to beat the route recommendations.

https://www.fastcompany.com/3004319/brown-down-ups-drivers-v...

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#75

Post by msla »

jbob2000 wrote: post #63
payne92 wrote: post #23

I worked with a startup years ago that did these kinds of optimizations (for deliveries). The logistics & transportation market in the US is about a TRILLION dollars -- small optimizations can make a HUGE impact. The challenge for practical implementations is that there are lots and lots and lots of optimization factors that are very hard to account for. Often, you don't even know what they are until you try to autom…

You're all neglecting the biggest problem of all - the driver. All of this work is moot if Dorthy, who's been driving the same route for 40 years, will not change the route. And you can't get rid of Dorthy because there's nobody to replace her in Dinkysville, Flyoverstate.

There are any number of reasons for bus drivers to have to change, from route optimization to school redistricting to, back in the old days, having to pick up all the children, not just the White children. People aren't horses. They can accept change.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#76

Post by dclowd9901 »

chrisallenlane wrote: post #38
dclowd9901 wrote: post #18

Earlier quoted context omitted.

That doesn't work either: you get situations like the TSA artificially backing up airport security lines to "necessitate" budget increases. They should incentivize efficiency. In government, it would be citizen impact per employee. If you have more, you make more money, if you have less, you make less.

> citizen impact per employee. Do you think it would actually possible to quantify this in a way that: 1. Accurately represented "reality"? 2. Couldn't/wouldn't be gamed? Seems challenging to me.

I think you can probably boil impact down to several key metrics:

1) How many people are affected by the work of this agency

2) How quickly are peoples' needs handled on average

3) How pleased are people with the work of this agency

I think you could trivially measure each of those.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#77

Post by dylanh »

mulmen wrote: post #73
ztakeo wrote: post #39

Earlier quoted context omitted.

Not sure if by "converting" you mean retrofitting old buses or replacing diesel buses with new electric buses. If it's the former definition, it's non-trivial from a safety and engineering standpoint to integrate a high-voltage, high-energy battery system into an old bus and expect to realize a decent ROI. Those old clunkers are not designed with an electric powertrain nor efficiency (i.e. they're heavy and have have…

I would argue that efficiency is more important in a school bus than safety. Buses are designed for many years of service with long-lived and easy to replace parts. On the safety front they are painted yellow and have some lights. That's pretty much it. They don't even have seat belts. It looks to me like efficiency trumps safety in this case.

It is reasonable to assume that safety is the primary concern for school buses. There are are a lot of safety standards.

"Pursuant to these requirements, federal safety regulations applicable to bus manufacturers have been developed. There are a total of 37 federal motor vehicle safety standards that apply to school buses. Many of these also apply to other types of motor vehicles, but several (among them standards 131, 220, 221, and 222) are written specifically for school buses."[1]

As for seatbelts,

"Large school buses are heavier and distribute crash forces differently than passenger cars and light trucks do. Because of these differences, bus passengers experience much less crash force than those in passenger cars, light trucks and vans."[2]

It seems that even weight[3] is a safety consideration.

[1] https://www.cga.ct.gov/2004/rpt/2004-R-0730.htm [2] https://www.nhtsa.gov/road-safety/school-buses [3] http://www.americanschoolbuscouncil.org/love-the-bus/educato...

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#78

Post by abakker »

Govindae wrote: post #64
abakker wrote: post #55

Earlier quoted context omitted.

Ah, the mythical budget vector.

Oh hey budget space must have an L1 norm. That's neat.

Pretty soon, we'll see the new consulting offering from McKinsey: Vector-based Budgeting. Very useful helping to mathematically quantify your various business unit's planning cycles in infinite dimensional space. You thought ZBB was cool, VBB is even cooler.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#79

Post by cropsieboss »

mck- wrote: post #46

Given the scale of the problems they are tackling, I'm quite surprised how little they are saving. $5m over $120m is only 4%. I would imagine municipalities' manual route planners wouldn't be that great. We have found with many real-world scenarios, that at a much smaller scale we could save easily up to 40% in driving time and fuel costs. When we studied cases of 20+ vehicles and ~1000 stops, sometimes the savings w…

These are all just savings numbers for simplified problems, like vehicle routing problem or simple pickup & delivery problem.

Points below properly define problem above:

* capacitated pickup and delivery with time windows (NP-hard)

* capacity of around 20-60

* every child has to stay maximum T minutes in the bus from the moment it is picked up

* each bus can work simultaneously on delivering to multiple schools (covered by standard p&d algorithms)

* additional routing/map constraints for roads/vehicle constraints - like minibus drivers being constrained to ares with different housing etc.

I'm pretty sure the third point is a tricky one, implementation and speed wise, last one too. I'm skeptical that your API could solve the problem for 600 vehicles off-the-shelf. Not to mention that pickup&delivery slows things down extremely compared to capacitated VRP. Each optimising step is a venture into heavy graph theory. Or one can use easy heuristics and fail miserably by exploring too little of constrained space.

I'm skeptical of these large savings. I've personally worked with some top logistics people that did amazing things with pencils and rulers. Trumping these methods gained savings of about 10-15%.

Not to mention the optimizing time. It is impossible (if algorithm is not heavily optimized) to search through enough space for these heavily constrained problems in short amount of time (couple of minutes) to get 60% savings. I might be too critical, but I doubt that Common Lisp algorithm can achieve those kinds of speeds.

What if a child was forgotten, how much will the replanning time impact the real world workflow. All sorts of invisible issues.

Re: MIT team’s school-bus algorithm could save $5M and 1M bus miles

#80

Post by mightytightywty »

$120M budget to bus 30,000 children to school? Does that sound like a lot, or is it just me? That's $4,000 per child per year. At 180 school days per year, that's $22.22 per child per day!

At that rate, they could save many more millions by switching to Uber or some other ride sharing service.

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