How To Get Into Cars: Hypermiling Mods

October 2, 2020 by Lewin Day 58 Comments

While we’re currently in an era of comparatively low gas prices, the last few decades have seen much volatility in the oil market. This can hit the hip pocket hard, particularly for those driving thirstier vehicles. Thankfully, modifications can help squeeze a few extra miles out of each gallon of dinosaur juice if you know what you’re doing.

The art of striving for the best fuel economy is known as hypermiling, and involves a broad spectrum of tricks and techniques to get the most out of a drop of fuel. Let’s dive in to how you can build a more efficient cruiser for getting around town.

Step 1: Know Thine Enemy

The MPGuino is a great solution for monitoring fuel consumption in older cars without a trip computer.

If you want to improve your fuel economy, the first step is to measure it. Without accurate measurement, it’s impossible to quantify any gains made or optimise for the best performance. For those with modern cars, it’s likely that there’s already a trip computer built into the dash. Using this to track your fuel economy is the easiest solution. Instantaneous modes are useful to help improve driving habits, while average modes are great for determining the car’s economy over time.

However, many older vehicles don’t have such features installed as stock. Thankfully, there’s a few ways to work around this. For those driving post-1996 vehicles outfitted with an OBD-II port, tools like Kiwi or Scangauge can often track fuel economy. Failing this, most fuel injected cars can be fitted with a device like the MPGuino that monitors fuel injection to calculate consumption. Fundamentally, all of these tools involve tracking the amount of fuel used per distance travelled. Factory tools and OBD-II gauges do it by using the car’s standard hardware, while the MPGuino splices in to speedometer signals and injector triggers to do the same thing with an Arduino. If you do decide to install a custom device, make sure you calibrate it properly, else your figures won’t bear much resemblance to what’s going on in reality.

Of course, as long as your car has a working odometer and a fuel tank that doesn’t leak, there’s always the pen-and-paper method. Simply reset the trip odometer to zero after filling the tank to the brim. Then, when refilling the tank, fill all the way to the top, and divide the miles driven by the gallons of fuel added back to the tank. This isn’t the most accurate method, as the nature of gas station pumps and automotive fuel tanks mean that tanks aren’t always accurately filled to the brim, due to air pockets and devices used to prevent overfilling. Despite this, it’s a handy way of getting some ballpark figures of your car’s performance over time.

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This Week In Security: PunkBuster, NAT, NAS And MP3s

October 2, 2020 by Jonathan Bennett 4 Comments

Ah, the ever-present PDF, and our love-hate relationship with the format. We’ve lost count of how many vulnerabilities have been fixed in PDF software, but it’s been a bunch over the years. This week, we’re reminded that Adobe isn’t the only player in PDF-land, as Foxit released a round of updates, and there were a couple serious problems fixed. Among the vulnerabilities, a handful could lead to RCE, so if you use or support Foxit users, be sure to go get them updated.

PunkBuster

Remember PunkBuster? It’s one of the original anti-cheat solutions, from way back in 2000. The now-classic Return to Castle Wolfenstein was the first game to support PunkBuster to prevent cheating. It’s not the latest or greatest, but PunkBuster is still running on a bunch of game servers even today. [Daniel Prizmant] and [Mauricio Sandt] decided to do a deep dive project on PunkBuster, and happened to find an arbitrary file-write vulnerability, that could easily compromise a PB enabled server.

One of the functions of PunkBuster is a remote screenshot capture. If a server admin thinks a player is behaving strangely, a screenshot request is sent. I assume this targets so-called wallhack cheats — making textures transparent, so the player can see through walls. The problem is that the server logic that handles the incoming image has a loophole. If the filename ends in .png as expected, some traversal attack checks are done, and the png file is saved to the server. However, if the incoming file isn’t a png, no transversal detection is done, and the file is naively written to disk. This weakness, combined with the stateless nature of screenshot requests, means that any connected client can write any file to any location on the server at any time. To their credit, even Balance, the creators of PunkBuster, quickly acknowledged the issue, and have released an update to fix it.

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Even More Firmware In Your Firmware

October 1, 2020 by Kerry Scharfglass 13 Comments

There are many ways to update an embedded system in the field. Images can fly through the air one a time, travel by sneaker or hitch a ride on other passing data. OK, maybe that’s a stretch, but there are certainly a plethora of ways to get those sweet update bytes into a target system. How are those bytes assembled, and what are the tools that do the assembly? This is the problem I needed to solve.

Recall, my system wasn’t a particularly novel one (see the block diagram below). Just a few computers asking each other for an update over some serial busses. I had chosen to bundle the payload firmware images into the binary for the intermediate microcontroller which was to carry out the update process. The additional constraint was that the blending of the three firmware images (one carrier and two payload) needed to happen long after compile time, on a different system with a separate toolchain. There were ultimately two options that fit the bill.

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Certifying Nuclear Reactors: How The NRC Approved Its First Small Modular Reactor Design

October 1, 2020 by Maya Posch 38 Comments

The US Nuclear Regulatory Commission (NRC) recently announced that it had approved certification of NuScale’s SMR (small modular reactor) design, completing its Phase 6 review of NuScale’s Design Certification Application (DCA). What this means is that SMRs using NuScale’s reactor design can legally be constructed within the US as soon as the rulemaking process completes. An NRC certification would also mean that certification of the design in other countries should pose no significant hurdles.

A question that remains unanswered at this point for most is how this certification process at the NRC actually works. Are there departments full of engineers at the NRC who have been twiddling their thumbs for the past decades while the US nuclear industry has been languishing? What was in the literally millions of documents that NuScale had to send to the NRC as part of the certification process, and what exactly are these six phases?

Stay tuned for a crash course in nuclear reactor certification, after a bit of SMR history.

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Choosing The Right RTC For Your Project

September 30, 2020 by Lewin Day 27 Comments

When it comes to measuring time on microcontrollers, there’s plenty of ways to go about things. For most quick and dirty purposes, such as debounce delays or other wait states, merely counting away a few cycles of the main clock will serve the purpose. Accurate to the tens of milliseconds, they get the average utility jobs done without too much fuss.

However, many projects are far more exacting in their requirements. When you’re building a clock, or a datalogger, or anything that relies on a stable sense of passing time for more than a few minutes, you’ll want a Real Time Clock. So called due to their nature of dealing with real time, as we humans tend to conceive it, these devices take it upon themselves to provide timekeeping services with a high degree of accuracy. We’ve compiled a guide to common parts and their potential applications so you can get things right the first time, every time.

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Video: Exploring The Abandoned Birthplace Of The 6502 And Commodore 64

September 30, 2020 by Bil Herd 65 Comments

I miss my friend Dave DiOrio. He was a chip designer in the 1980’s, which made him one of the true wizards back then. We met my first day when I started at Commodore Business Machines, though my paycheck said MOS Technology on it.

MOS Technology was the birthplace of the venerable 6502 microprocessor, the VIC video chip, and the SID sound chip to name the really famous ones. It also brought us the TED Text Display chip, a whole boatload of Amiga chips, and several other chips that almost did what we wanted them to do.

I worked with magicians whose stock and trade were comprised of half-part quantum tunneling effect and half-part straight-up logic implementation. These magicians weren’t bound by the number of pins available for TTL logic, not like us lowly hardware engineers who had to string 14 and 16 pin chips together to do any real lifting.

Below the spartan offices where the designs were drawn lived the dragon otherwise known as a chip fab, short for integrated circuit fabrication plant. This beast ate sand and made wafers; slices of almost pure silicon in crystalline form with all kinds of intricate things craftily grown on top of them.

Memory Lane: Touring the Abandoned MOS Headquarters

MOS Technology was started in 1969 by Allen Bradley but only became the MOS that I think of when I talk about the good old days when Chuck Peddle and a bunch of cohorts from Motorola, including Bill Mensch, swept in and produced the 6502 microprocessor, which resembled a particular Motorola processor quite a bit, in fact a lot. Lawsuits followed.

Meanwhile the 6502 was taking over several industries as the go-to processor for everything from medical equipment to microwave ovens to home computers. It was while designing home computers that I met Dave while standing above a chip fab. I can still remember the smell of that dragon farting below our feet… its an understatement to say I miss those times.

A couple of years ago I had a chance to return to the old stomping ground as it were, and set foot (legally) inside of MOS headquarters in Norristown, PA — which had become CSG (Commodore Semiconductor Group) by the end. The basement was dirty and flooded and yet we found wafers, one from one of the computers I worked on.

The ground floor was dark and quiet, I stood at the dirty glass entrance doors looking out at a drab street and I quickly moved on before I got hit by some sort of self evident metaphor for life that would have been annoying.

The second floor was where our offices had been. The hot press of design deadlines has long since left this space, now all there is to see is the golf course out the window and a little camp fire someone had made. I got to show this video to Dave, including the view looking out his old office window, and we both smiled at the thought that it was now 35 years later.

Dave has since passed away, the world has one less wizard and as the video shows, the dragon has long since gone quiet.

A Good, Hard Look At Pre-Stressed Concrete

September 29, 2020 by Kristina Panos 43 Comments

From the looks of the average driveway or sidewalk, it may seem as though concrete is just destined to crack. But if concrete is so prone to cracking, how are we able to use it in so many high-stress applications like bridges and skyscrapers? This question came about while I was researching 3D-printed thermite for an article. Thermite is often used in welding railroad tracks, and I linked a video of fresh tracks being welded that had concrete ties. I knew I had to find out how concrete could be made to withstand the pressure of freight trains.

On its own, concrete is brittle and has no give to it at all. But that doesn’t mean it isn’t strong. Although concrete has good compression strength, the tensile strength is quite poor. Around the late 1800s, someone thought to fortify spans of concrete with steel reinforcing bars, better known as rebar. Steel can stretch, adding steel bars gives the concrete some tensile strength to go along with its compressive strength. Rebar also allows for thinner slabs and other members.

Rebar Only Goes So Far

Parking blocks are meant to be replaced occasionally. Image via Checkers Safety

Rebar or mesh-enforced concrete is good for things like parking lot blocks and roads, but it still fails before it ought to. In fact, it usually has to crack before the rebar can chip in any of its tensile strength.

In high-stress concrete applications like bridges and skyscrapers, it’s terrifically important to avoid deflection — that’s when a concrete member flexes and bends under load. Deflection can cause the modern glass skins to pop off of skyscrapers, among other problems.

A solid, rigid bridge is much nicer to walk, drive, and bicycle on than a bridge that sways in the breeze. But how do you do make a rigid bridge? One solution is to apply stresses to the concrete before it ever bears the load of cars and trucks or a steady schedule of freight trains.

Pre-stressed concrete is like rebar-enforced concrete, but with the added power of tension baked in. By adding stress to the concrete before it goes into service, deflection will be reduced or perhaps eliminated altogether. With the addition of tensile strength, more of the concrete’s own strength is able to come into play.

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