Posts by Jan (Page 2)
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Most of the products we manufacture are small electronics subassemblies, which we have been packaging in these pink antistatic bags that are probably familiar to everyone who has worked with electronics:
These bags are supposed to help prevent charge buildup and therefore help prevent the sensitive components inside from getting damaged just from the bags being shuffled around. But, if you charge yourself up and then grab the bag, you can still zap the electronics inside through the bag.
This year, we began transitioning our packaging to metalized shielding bags, like this:
These bags have the charge buildup prevention of the pink bags but also have a metal layer that prevent the spark from getting from your finger to the electronics parts in the bag. Most bags I have seen have some plastic coating outside the metal layer so that you don’t have zero resistance along the surface of the bag, but I have heard of people shorting things out by powering them up while sitting on some types of metallic bags.
Did a static discharge into a USB port cause this power supply to go up in smoke?
I once got a huge static shock when I plugged a flash drive into my USB port, and right after that, a bunch of sparks and smoke came out of my computer’s power supply. I’m pretty sure that wasn’t a coincidence, but I still can’t be sure it was a case of electrostatic discharge (ESD) destroying my computer. And usually, ESD damage is much more subtle and basically impossible for us to confirm. So, changing the packaging is one of those things where it will be very difficult to tell if it’s really doing anything. But we go through a lot of effort to inspect and test each item we make so that we can be confident it worked when we made it, so this packaging change should give us still more confidence that the part is in good condition when you receive it. It will take a while before all of our products get changed over, so don’t be shocked if your order arrives with a mix of packaging types.
I am excited to announce the release of the Balboa robot! The Balboa is a two-wheeled balancing robot platform that is small enough to tempt you to run it on a desktop, but it’s quick enough that you should probably stick to bigger, softer surfaces. Or at least put a safety net or foam pit around your desk. Here is a short video showing it kicking up into balancing position and driving around:
A look inside the external gearbox on the Balboa 32U4 Balancing Robot.
One of our main goals in designing our robots is to make them complete and engaging on their own while making them open and expandable enough for all kinds of projects. We also don’t want them all to be the same. Most of the Balboa robots in our pictures have 80 mm wheels, but the chassis can also work with our 90 mm wheels (and to a lesser, barely practical extent, our 70 mm wheels). Because the chassis is made for our micro metal gearmotors, you have a few options for gear ratios as with our Zumo sumo robots, but what’s really exciting about the Balboa design is that there is an extra stage of gear reduction for which you get five different options (all included, and you can easily change the gear ratio from whatever you initially choose). The design also allows the drive wheels to be supported on ball bearings, reducing the stress on the micro metal gearmotor output shafts.
The Balboa chassis has a built-in battery holder for six AA cells, which typically give you several hours of run time, even if you add some extra power-hungry electronics like a Raspberry Pi.
Balboa 32U4 Balancing Robot with battery cover removed.
The main microcontroller is an Arduino-compatible ATmega32U4, which is powerful enough to read the on-board IMU sensors and encoders and to control the motors to balance the robot; it’s also great for introductory projects like line following or reading an RC receiver to make a radio-control balancing robot. For advanced projects, the Balboa is ready for you to add a Raspberry Pi computer to perform high-level algorithms while the ATmega32U4 microcontroller takes care of low-level tasks like motor control.
We will be adding more content to the Balboa’s product page and user’s guide, and we will have more blog posts about the Balboa robot. For today, we’ll end with some slow-motion footage of Balboa popping up on its own and then recovering when Paul knocks it around a bit:
It’s been more than two years since my last post. I thought I would post an update a year ago, when Eve was born, but that didn’t go very well, and the uncertainty about how things would turn out with her made it difficult to rally around her birth as some celebratory point from which to start moving on. I feel at once as if I have lost two years of my life, making no progress, and yet that my life has completely transformed in that time. But I know things have gotten better because I am usually free of the sadness and fear that still filled me a year ago, around Dez’s first birthday. Continued…
This blog post is about some personal difficulty I’m going through: last month, my baby died unexpectedly a day or two before he was born. I could just collect my thoughts in my private journal, but I am sharing my experience here on the Pololu blog because most of the people I interact with and care about are related to Pololu, be they friends, employees, vendors, or customers. Just about everyone at Pololu knew of my eager anticipation of this new baby, and any visitors were aware that I might miss our meetings with short notice depending on when the baby arrived. Continued…
Everyone wants encoders on their motors. If you think you don’t, you just don’t know it yet. I think the main reason is that we really just want motors to do what we tell them to do, but they don’t. One of the most common beginner questions we get is some variation of, “why doesn’t my robot go straight?” or “I got two of the same motor but they do not go the same speed; is something wrong with one of them?” More seasoned robot builders know that since there will always be variations in everything that contributes to a motor’s performance, our best hope is to put a sensor on the motor to monitor what is actually happening and then adjust the motor control to make reality better match our desires. Continued…
We recently substantially reduced prices on our stepper motor driver carriers, and I figured this announcement was a good time to give you an update on our perspective and capabilities.
It has been over five years since I designed our original stepper motor driver carrier, which was for the A4983 from Allegro. While fairly straightforward, the implementation reflected several design philosophies that go into Pololu products, such as making the boards as small as practical and including the right extra components to make the main chip easily usable without unnecessarily limiting its features. Continued…
I received a phone call yesterday from a writer for a local community-oriented, general-interest publication. Pololu is one of a dozen or so companies she was covering in an article about technology-related companies in southern Nevada, and she asked some basic questions about Pololu and how we might be relevant to Las Vegas-area locals. She then asked if there was anything else I would like to add or have mentioned about us. I answered that since I wasn’t really clear on what this article was going to be or what the intended audience was, I did not know what would be appropriate or interesting. I suggested that she could send me a draft of her article so that I might have a better context for giving her additional info. Continued…
Modulated IR detectors typically used for remote control of household electronics have long been used in robot sensors because they are small, cheap, and very sensitive while still blocking out unwanted interference. However, part of what makes the modules so good for remote control is their complex automatic gain control (AGC) circuitry that adjusts the sensors’ sensitivity to ambient lighting conditions to give clean, digital outputs in a variety of environments. Unfortunately for those using the modules for other purposes, all of that magic is internal to the modules and leads to two shortcomings: we cannot know how strong the optical signal is because we do not know the gain value, and we cannot have consistent behavior because we cannot control how the AGC behaves.
Pololu 38 kHz IR proximity sensor (original irs05a version).
So, you can imagine how excited I was to find out about Vishay’s new IR modules designed specifically for sensor applications. They have two basic versions: one with a fixed gain that is constantly super-sensitive, and another one with a predictably-varying AGC that lets you know how bright the incident IR is. We used the fixed-gain units on the IR proximity sensors we released earlier this year, and we plan to make more products that use these unique sensors. In the meantime, we are happy to offer the through-hole versions of these sensors so you can start playing around with them to make your own sensor systems. Here are the two parts:
- The Vishay TSSP58038 has a fixed high gain setting, so it responds predictably and can detect a continuous modulated signal.
- The Vishay TSSP58P38 includes automatic gain control – but it is tuned to provide a usable measurement of the strength of the detected signal. When configured as a reflective proximity sensor, its output is a pulse with a width that depends almost linearly on the distance to the target.
Those IR proximity sensors I mentioned earlier work nicely with these new sensors since our boards include a high-brightness LED with a 38 kHz modulation circuit, so you can use several of those with these new IR detectors to make sophisticated sensing solutions in which you enable one emitter at a time and monitor the reflections with all the other sensors.
We expect to release a simple carrier for ST’s new LPS331AP pressure sensor this week. While testing and writing example programs for the sensor, one of our engineers, Kevin, came up with a nice demonstration that calculates and displays the altitude on our Orangutan SVP robot controller. It was a beautiful spring day with great flying weather, so Paul and I took Kevin’s digital altimeter on a flight to Lake Havasu City, Arizona, to see how it compared to the altimeter in a plane. Continued…
I posted toward the end of last year about some new equipment we were adding to our manufacturing operations and said the best stuff was still coming. I and several others at Pololu have since had some more personal deliveries of the crying-all-night sort, which delayed my promised update. I still do not have the performance information I had hoped to have by now, but let’s at least look at what we got: Continued…