Tag Archives: hardware

I’ve been on some extensive travel lately and as Chris Gammell related travelling for engineering is no easy task. Making sure you have all your necessary test equipment and access to all the resources you might need involves a lot of planning. But sometimes things just don’t work out in your favor. I’ve talked about testing to failure before. However, plenty of times when you are not anticipating failure it happens anyways: Murphy strikes again. The problem is in dealing with your failure. Very often it’s unclear whether you caused a component to fail or whether you had a bad component to begin with. Miss MSE just talked about how engineers need to be good storytellers. Unfortunately there’s very often no good story to tell. If it was your equipment that caused the failure (but you can’t figure out how) that sort of implies you’re due for future failure. Or…

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Failure is not always a bad thing. Sometimes it’s exactly what you want. You might start with one component that’s been well tested with the existing system. It can be a simple clamp or a complicated swing valve (like the one pictured from DHV Industries). You probably tested it out when it was originally implemented and proved you had plenty of safety margin. But now your system has changed. Maybe you’re sending your system into freezing winter temperatures or hot, arid deserts. Maybe you’ve got a more powerful compressor that generates much higher pressures than you’d been dealing with before. So how do you test that component? Most standards would suggest you take your max operating conditions and increase the magnitude by 50% and test at those conditions. That proof test would verify your equipment can operate safely at your max conditions giving you a 1.5 safety margin. But in…

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I’ve been thinking a lot about the variety of authors we have at Engineer Blogs. We have a mix of  academic and industry engineers and each arena provides its own challenges and goals. But one major thing we have in common is probably getting the test equipment you need. In the photo, USN avionics technician Norton is repairing a test bench (via Morning Calm News). Test equipment can kind of run our lives and our schedules if we aren’t careful. Academics are probably familiar with scheduling time at strange hours and working around the other researchers and students who might need to share the same equipment. Those of us in industry have similar issues with whose project takes priority for the EMI chamber or the oven. Does heat treating a production piece after a weld take priority over an emergency investigation of a material that might be failing at lower…

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The big event that happened last week for me was the Open Source Hardware (OSHW) Summit 2011 (OHS). So this week I want to review the interesting talks that took place and what it means to me as a electronics design engineer. I’m guessing I am not the first or last to review the event, Jeremy Blum was at the event and you can check out his review on element14. So keep an eye out for other reviews too. I was unfortunately not at the summit physically, but like thousands of others, I watched online via uStream. Not the greatest way to watch as the slides were all blurred but free. There was some 20+ talks given by people with a range of experience in OSHW, all with equal interest; however, my favourites were as follows: The team (Jurgen and Alison) from OHANDA were the first to catch my eye…

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This week, I wanted to get a little more hardcore with the electronics and explain one of the products I once worked on: the Engine Control Unit (ECU) of a Formula 1 racing car. Some 10 years ago, I worked for a UK company that designed and built electronics for a large proportion of the racing world. From Formula Ford to World Rally cars, from go carts to NASCAR cars, their electronics found their way in. They designed things like data loggers, sensors, full car looms, and even the £50,000 steering wheels you used to see in the Ferrari Formula 1 cars. However, the really clever stuff was carried out inside the ECU. The basics of a car engine are easy to understand: suck in some air, mix a little fuel, add a little spark, and bang! You get a big explosion and lots of smelly gases which you throw…

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My specialty within Mechanical Engineering is Machine Design. These past couple weeks I have been designing a new machine, one that needs to be very precise. Basically the new machine is a stamping machine – I have a stamp coated with an ink, then I apply a force to press the stamp onto a substrate and transfer the inked pattern. The trick is that the two pieces (the stamp and the substrate) need to be carefully aligned so that the pattern ends up in the right place. The tolerance is pretty tight – I have to be within +/- 2 micrometers. It occurs to me that this specific design problem is part of the more general issue of fixturing and constraints. It’s a pretty common situation as engineer that you have one piece which needs to be aligned relative to another piece. So how do you do it? Well it…

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Hardware engineers everywhere in the world all have to deal with that black art know as Electromagnetic Immunity or Compliance (EMI / EMC). These are the nasty radio frequencies (RF) that blast and affect other equipment or your circuits. So in this blog I look at one time when the going got tough, we just added a little wiggle. The project I have in mind is a product that drives ‘something’ with a 400V DC square wave at around 200+ watts. The product contains a Power Factor Correction section (PFC) that takes in our normal supply voltage and using a continuous mode PFC circuit, boosts the voltage and regulates it to 400V DC. Now I’ll not go into how a PFC works, but the key point here is that the circuit has a large inductor used to store and boost the supply voltage. This inductor is cycled via a device…

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So some time back, I did a few blogs about how much I like writing VHDL and what a wonderfully language it is. I also did a bit of an intro for software engineers (don’t worry, you don’t need to read them to see where I’m going here). However, I came under a bit of criticism about what I wrote and my use of the evil STD_LOGIC_ARITH package. OK, I may not be a full-time VHDL engineer but I think there are far too many people being sheep and using the numeric library though peer pressure while not considering true engineering principles. So first off, let’s get this all straight – I class myself as a embedded electronics design engineer. My day job is all low-level electronics and microcontrollers, no FPGAs. However, I spent a few years working on a VHDL design for a Gigabit Ethernet Card where I looked…

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When a major hardware component goes it can often fail in catastrophic and spectacular ways. If your serpentine belt in your engine breaks not only does it mean your crankshaft stops but then by extension your alternator will stop charging your batteries which could result in power loss pretty quickly. Then your water pump would stop and your engine would start overheating while  simultaneously your power steering pump would quit meaning you’d feel like you went from driving a modern car to some sort of fifty year old tractor. Serpentine belts are treaded on the inside for this reason. Wear can be measured much like on your tires where the depth of the tread tells you how long you have left to go on it and you can also visually inspect for cracks. But in more complicated assemblies, a single point of failure isn’t always as obvious. The result can be catastrophic system…

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