A Transformable Workspace

No two workspaces or circuit cellars are alike. And that’s what makes studying these submissions so fascinating. Each space reflects the worker’s interests, needs, and personality.

Succasunna, NJ-based Mike Sydor’s penchant for “hacking” isn’t relegated solely to electronics. His entire workspace is actually a hack designed for both hardware and software projects. It’s an excellent example of what you can do with a little creativity and planning!

When the front is open, Mike can tackle hardware projects (Source: Mike Sydor)

We love the “transformer” theme that runs through the entire space. Simply put, the compact space is easily rearranged to serve Mike’s various needs:

  • When the front is closed, Mike can work on the “soft arts” of coding, diagramming, and design planning.
  • When the front is open, Mike has easy access to essential tools such as an oscilloscope, isolation transformer, and solder station.
  • A KVM switch enables Mike move back and forth between Linux and Windows

    Mike simply closes the front when he shifts from hardware mode to software mode (Source: Mike Sydor)

Another interesting point to note is that Mike can detach the shelf/drawer so the workspace can fit through a door if necessary. Great idea! Now he can take the workspace with him if he ever moves.

Submitted by Mike Sydor:

Here is my workspace for your consideration.  It is basically a custom, drop-front workspace on wheels so that I can move it easily to reconfigure the equipment or otherwise get to all the gear.  It has two configurations.  The ‘software’ setting (front closed) where I can focus on the code, design docs, etc.  The shelf can also hold a midi keyboard for music ‘hacking.’  There is a drawer in that shelf for miscellaneous items.  With the front open, you have a nice workspace for assembly and debugging, you can still access the drawer, and you can access all of the gear.  Everything is self-contained – only a single power and network cable are ‘on the floor.’  The shelf/drawer assembly detaches for moving day – otherwise it is too wide to fit through a standard door opening.  I also only use three wheels.  This makes a tripod, which is stable on any surface.  I live in an older home – no level floors! – so mobility does not compromise stability and I don’t have to shim one side or the other to keep it from wobbling.   The mass of all the gear keeps the bench stable.  The monitors are mounted on a custom stand so that they can be positioned, via swing arms and are otherwise stable when you need to move the bench around.  I use a KVM switch with multiple computers (windows, Linux) and have a set of cables so that I can plug in a project computer and use the same monitors and keyboard.  All the computers are on the same switch for optimal Ethernet performance.  I build kits, prototype circuits for sensor conditioning and muck around with micro-controllers, as well as fix/hack your various consumer electronics.  Cheers, Mike Sydor.

All the good stuff in one place! Power, a solder station, a scope, and more! (Source: Mike Sydor)

Do you want to share images of your workspace, hackspace, or “circuit cellar”? Send your images and space info to editor<at>circuitcellar.com.

A Rat’s Nest-Less Workspace: Clean with Plenty of Screens

Two sorts of things we love to see in an electronics workspace: cleanliness and multiple monitors! San Antonio, TX-based Jorge Amodio’s L-shaped modular desk is great setup that gives him easy access to his projects, test equipment, and computers. The wires to all of his equipment are intelligently placed behind and below the workspace. Hence, no rat’s nest of wires! He doesn’t need to work on top of cords and peripherals like, well, a few of us do here in our office. We like how he “sectioned” his space to provide maximum multitasking capability. The setup enables him to move easily from doing R&D work to emailing to grabbing his iPhone without any more effort than a slide of his chair. Very nice.

Jorge Amodio's workspace (Source: J. Amodio)

Submitted by Jorge Amodio, independent consultant and principal engineer (Serious Integrated, Inc.), San Antonio, TX, USA

“For the past few years I’ve been working on R&D of intelligent graphic/touch display modules for HMI (Human Machine Interface) and control panels, with embedded networking for ‘Internet of Things’ applications.” – Jorge Amodio

Jorge perform R&D with handy test equipment an arm's length away (Source: J. Amodio)

A closer look at Jorge's project space (Source: J. Amodio)

Jorge has easy access to his other monitors and iPhone (Source: J. Amodio)

Do you want to share images of your workspace, hackspace, or “circuit cellar”? Send your images and space info to editor at circuitcellar dotcom.

User Interface Innovation: Collaborative Navigation in Virtual Search and Rescue

An engineering team from Virginia Tech’s Center of HCI and Department of Computer Science recently won first place in the IEEE’s 2012 3DUI Contest the for their Collaborative Navigation in Virtual Search and Rescue Escort (CARNAGE) project. The project was designed to enable emergency responders to collaborate and safely navigate a dangerous environment such as a disaster area.

The contest was open to researchers, students, and professionals working on 3-D user interface technologies. Entrants were challenged to design an application to enable two users—situated in different locations with his or her own UI—to navigate a 3-D environment without speaking to each other.

Collaborative Augmented Rescue Navigation and Guidance Escort UI (Source: Virginia Tech News, YouTube)

The Virginia Tech team—comprising Felipe Bacim, Eric Ragan, Siroberto, and Cheryl Stinson—described their design in a concise system description, which is currently available on the 3DUI 2012 contest website:

Our task specifically looks at communication between a scene commander and a disaster relief responder during a search and rescue operation. The responders inside the environment have great difficulty navigating because of hazards, reduced visibility, disorientation, and lack of survey knowledge of the environment. Observing the operation from outside of the disaster area, scene commanders work to help coordinate the response effort  [1, 2]. With the responder’s notifications about the environment, scene commanders can provide new instructions, alert the responders to risks, and issue evacuation orders. Since neither the commander nor the responder has complete information about the environment, effective communication is essential.

As technology advances, the incorporation of new tools into search and rescue protocols shows promise for improving  operation efficiency and safety. In this research, we explore the  use of 3D user interfaces to assist collaborative search-and-rescue. Ideally, users should be able to focus on their primary tasks in the VE, rather than struggle with travel and way finding. Using virtual reality (VR) as a prototyping testbed, we implemented a proof-of-concept collaborative guidance system. Preliminary evaluation has demonstrated promising results for efficient rescue operations.

The team also created an explanatory 6:16-minute project video:

Click here for more information about the IEEE Symposium on 3D User Interfaces in Costa Mesa, CA.

Source: Virginia Tech News


Issue 263: Net-Enabled Controller, MCU-Based Blood Pressure Cuff, MOSFETs 101, & More

Although the June issue is still in production, I can report that it’s packed with projects and tips you’ll find immediately applicable. The projects include an AC tester design, an Internet-enabled controller, a DIY image-processing system, and an MCU-cased blood pressure cuff. Once you’ve had your fill of design projects, you’ll benefit from our articles on essential topics such as concurrency embedded systems, frequency mixers, MOSFET channel resistance, and “diode ORing.”

An Internet-Enabled Controller, by Fergus Dixon
Power-saving smart switches require a real-time clock-based controller. With a request for an Ethernet interface, the level of complexity increases. Once the Ethernet interface was working, connecting to the Internet was simple, but new problems arose.

Final PCB with a surface-mount Microchip Technology ENC28J60 Ethernet chip (Source: F. Dixon, CC263)

AC Tester, Kevin Gorga
The AC Tester provides a modular design approach to building a tool for repair or prototyping line voltage devices. In its simplest form, it provides an isolated variable AC voltage supply. The next step incorporates digital current and voltage meters with an electronic circuit breaker. The ultimate adds an energy meter for Watts, VA, and VAR displays.

The AC Tester powered up and running. The E meter is shown in the plastic case on the top of the tester. The series current limit bulbs are on the top. (Source: K. Gorga, CC263)

Image Processing System Development, by Miguel Sánchez
Some computer vision tasks can be accomplished more easily with the use of a depth camera. This article presents the basics on the usage of Microsoft’s Kinect motion-sensing device on your PC for an interactive art project.

Build an MCU-Based Automatic Blood Pressure Cuff, by Jeff Bachiochi
Personal health products are becoming more and more commonplace. They reinforce regular visits to personal physicians, and can be beneficial when diagnosing health issues. This article shows you how to convert a manual blood pressure cuff into an automatic cuff by adding an air pump, a solenoid release valve, and a pressure sensor to a Microchip Technology PIC-based circuit.

A manual blood pressure cuff adapted into an automatic cuff by adding an air pump, a solenoid release valve, and a pressure sensor to a microcontroller. (Source: J. Bachiochi, CC263)

Concurrency in Embedded Systems, by Bob Japenga
This is the first in an article series about concurrency in embedded systems. This article defines concurrency in embedded systems, discusses some pitfalls, and examines one of them in detail.

Radio Frequency Mixers, by Robert Lacoste
Frequency mixers are essential to radio frequency (RF) designs. They are responsible for translating a signal up or down in frequency. This article covers the basics of RF mixers, their real-life applications, and the importance of frequency range.

MOSFET Channel Resistance: Theory and Practice, by Ed Nisley
This article describes the basics of power MOSFET operation and explores the challenges of using a MOSFET’s drain-to-source resistance as a current-sensing resistor. It includes a review of fundamental enhancement-mode MOSFET equations compared with Spice simulations, and shows measurements from an actual MOSFET.

Diode ORing, by George Novacek
Diode ORing is a commonly used method for power back up. But there is a lot more behind the method than meets the eye. This article describes some solutions for maintaining uninterrupted power.

The June issue will hit newsstands in late May.

Hollow-State Amps & Frequency Response

“Glass audio” has been growing in popularity among average audio enthusiasts for the past decade. Music-loving consumers worldwide enjoy the look and sound (i.e., the “warmth”) of tube amps, and innovative companies are creating demand by selling systems featuring tubes, iPod/MP3 hookups, and futuristic-looking enclosures. I suspect hybrid modern/retro designs will continue to gain popularity.

Many serious audiophiles enjoy incorporating glass tubes in their custom audio designs to create the sounds and audio system aesthetics to match their tastes. If you’re a DIYer of this sort, you’ll benefit from knowing how amps work and understanding topics such as frequency responses. In the April 2012 issue of audioXpress, columnist Richard Honeycutt details just that in his article titled “The Frequency Response of Hollow-State Amplifiers.”

Below is an excerpt from Honeycutt’s article. Click the link at the bottom of this post to read the entire article.

Early electronic devices were intended mainly for speech amplification and reproduction. By the 1930s, however, musical program material gained importance, and an extended frequency response became a commercial necessity. This emphasis grew until, in the 1950s and 1960s, the Harmon Kardon Citation audio amplifier claimed frequency response from 1 to 100,000 Hz flat within a decibel or better. Although today, other performance metrics have surpassed frequency response in advertising emphasis—in part because wide, flat frequency response is now easier to obtain with modern circuitry—frequency response remains a very important parameter …

Just which factors determine the low- and high-frequency limitations of vacuum tube amplifiers? In order to examine these factors, we need to discuss a bit of electric circuit theory. If a voltage source—AC or DC, it doesn’t matter—is connected to a resistance, the resulting current is given by Ohm’s Law: I = V/R. If the voltage source is of the AC variety, and the resistor is replaced by a capacitor or inductor, the current is given by: I = V/X where X is the reactance of the capacitor or inductor. Reactance limits current flow by means of temporary energy storage: capacitive reactance XC does so via the electric field, and inductive reactance XL stores energy in the magnetic field.

Figure 1 - The values of reactance provided by a 0.1-μF capacitor and a 254-mH inductor, for a frequency range of 10 to 30,000 Hz (Source: R. Honeycutt, AX April 2012)

Figure 1 shows the values of reactance provided by a 0.1 μF capacitor and a 254 mH inductor, for a frequency range of 10 to 30,000 Hz. Notice that capacitive reactance decreases with frequency; whereas, inductive reactance increases as frequency increases.

Click here to read the entire article.

audioXpress is an Elektor group publication.