Team-Based Engineering

On August 6, 2012, NASA’s Curiosity rover successfully landed in Gale Crater on Mars after traveling a daunting 352 million miles. It was a triumphant moment for the scores of Curiosity team members who had spent years engineering the mission. And it has become the archetypal example of the benefit of team-based, multidisciplinary engineering.

This is an image of the Mars Hand Lens Imager (MAHLI) located on Curiosity’s arm. (Source: NASA/JPL-Caltech/MSSS)

In Circuit Cellar 267 (October  2012), Steve Ciarcia refers to the Curiosity effort as a point of departure for expounding the importance teamwork and intelligent project management.  He argues that engineering endeavors of all sorts and sizes require the extraordinary focus and collaboration of multiple specialists all working toward a common goal.

Several weeks ago, I was following the successful landing of the Curiosity rover on Mars, which got me reminiscing about the importance of teamwork on large engineering projects. Obviously, a large project requires a significant number of people due to the sheer amount of work. But, more importantly, a project’s various tasks require a balanced mix of skills for successful and timely completion.

Naturally, you want engineers working in areas where they have the skills and confidence to succeed. That’s when they’ll do their best work. At a basic level, all engineers share a distinctive trait: the ability to make something you want from technology and materials. This is the best definition of “engineer” I have heard. But, as I said last month, different engineers have different interests, skills, and experience. Some engineers are good at understanding the subtleties of how a large systems’ components interact, while others are good at low-level details (e.g., analog circuit design, mechanical design, or software programming). Diversity of skills among team members is important and can greatly strengthen a team.

At some point, we all look to ascend the corporate ladder and, for most companies, that involves engineers taking on management responsibilities. Actively encouraging engineers to work in areas outside their comfort zones encourages greater diversity in problem-solving approaches. Further, inspiring engineers to seek responsibility and expand their comfort zones can make them better engineers for the long term. While this is mainly true about engineers who are employees, it also applies to any contractor or consultant involved in a long-term company relationship.

Some engineers can jump into just about any area and do well. However, it is rarely in the interest of the project or good team dynamics to follow that impulse. Those engineers need to enable the specialists to do the work they’re best at and only jump into situations where they can do the most good. In other words, when team management is your primary task, engineer or not, you need to take on a mentoring role, often teaching rather than doing.

Communication among team members is also key. There must be enough of it, but not too much. I have seen teams schedule so many meetings there isn’t any time left for individuals to make progress on their assigned tasks. Meetings need to be short, to the point, and involve only those people who have a vested interest in the information being exchanged. This can range from two engineers conversing in a hallway to a large project-wide meeting that keeps everyone in sync on a project’s overall goals and status. But beware, it can be difficult to keep big meetings from getting diverted into the minutiae of a particular problem. This needs to be avoided at all costs.

Even when the schedule is tight, overstaffing usually has a negative benefit. The math suggests that project completion time should go down by the inverse of the number of team members. However, this ignores the overhead of more communication among team members, which goes up by the square of the number of participants. If there are too many team members, they may start getting in each other’s way and have less sense of ownership in what they’re doing. Basically, there are some tasks that take a fixed amount of time. As the saying goes, nine women can’t make a baby in one month!

Motivating the team is another key factor that should be a priority shared by the team and technical management. No matter how large or small a team member’s assigned tasks, if he feels he has the responsibility and the recognition for getting that task done, he’ll be more engaged and motivated to do well. Moving team members from task to task destroys any sense of ownership. Granted, every project has the occasional fire that needs to be extinguished—all hands on deck—but, if a project is constantly in that state, then it’s pretty much doomed to fail.

Regardless of whether you are engineering a Mars rover at NASA or creating the next great social media “widget” at a venture-capital funded start-up, the dynamics of successful project management have an established methodology. Design engineers are creative and it is important to give them the flexibility to unleash their creativity—but keep it within bounds. Most projects are time and cost sensitive. Ratifying your step up the corporate ladder only comes by ensuring the project is completed within budget and in a timely fashion.

Circuit Cellar 267 (October 2012) is now available.

CC267: Continuity of Embedded Tech Content

The October issue features articles on topics ranging from FAT cache to IIR digital filters to a quadcopter that uses a mechanical gyro. Let’s review.

Jeff’s quadcopter uses a mechanical gyro that is “an inexpensive yet elegant attempt to counteract wind gusts.” With its protective shield removed, you can see the motorized spinning rotor that sustains equilibrium as its frame moves.

On page 16, Stuart Oliver details how to use math routines that include the dsPIC hardware features, such as the accumulators and barrel shifter. He uses the math for implementing Assembler routines.

Turn to page 30 to learn how Kerry Imming uses FAT cache for SD card access. You can implement his cache technique in a variety of other applications.

Before you start a new project, familiarize yourself George Novacek’s tips on managing project risk (p. 34). He explains how to define, evaluate, and handle risk. Better yet, why not just reduce risk by avoiding as many problems as possible?

Bob Japenga addresses this issue as well (p. 38). In the third part of his series on concurrency in embedded systems, he details how to avoid concurrency-related problems, which can be difficult because the more concurrency you add to a project, the more complicated it becomes.

Ed Nisley presented a MOSFET tester in his August 2012 article, “MOSFET Channel Resistance.” In this issue, Ed covers temperature measurement, the control circuitry, the firmware’s proportional integral control loop, and more (p. 42).

A fan under the black CPU heatsink keeps it near ambient temperature, so that the Peltier module under the aluminum block can control the MOSFET temperature. The gray epoxy block holds a linearized thermistor circuit connected to the Arduino microcontroller under the PCB. (Source: E. Nisley)

Check out Robert Lacoste’s article on page 58 for an introduction to IIR digital filters. You’ll learn about the differences between IIR filters, FIR filters, and analog filters.

WinFilter allows you to calculate and simulate all kind of IIR filters just by entering their key characteristics (left). The plots shows you the resulting frequency and time behavior. (Source: R. Lacoste)

Working with an unstable mechanical gyro? As Jeff Bachiochi explains, a MEMS system is the solution (p. 68).

Lastly, check out the interview with Helen Li on page 54. You’ll find her impressive research exciting and inspirational.

AC Tester Schematic Update

An error was found in one of the AC tester schematics that ran in Kevin Gorga’s June 2012 article, “AC Tester” (Circuit Cellar 263). As a reader indicated, T2 is disconnected in the published version of the schematic. An edited schematic follows.

Edited version of Figure 2 in K. Gorga’s June 2012 article, “AC Tester” (Source: Paul Alciatore)

The correction is now available on Circuit Cellar‘s Errata, Corrections, & Updates page.

2012 ESC Boston: Tech from Microchip, Fujitsu, & More

The 2012 Embedded Systems Conference in Boston started September 17 and ends today. Here’s a wrap-up of the most interesting news and products.


Microchip Technology announced Monday morning the addition of 15 new USB PIC microcontrollers to its line of full-speed USB 2.0 Device PIC MCUs. In a short presentation, Microchip product marketing manager Wayne Freeman introduced the three new 8-bit, crystal-free USB PIC families.

The PIC16F145x family (three devices) features the Microchip’s lowest-cost MCUs. The devices are available in 14- and 20-pin packages, support full-speed USB communication, don’t require external crystals, include PWM with complement generation, and more. They’re suitable for applications requiring USB connectivity and cap sense capabilities.

Microchip’s three PIC18F2x/4xK50 devices (available in 28- and 40/44-pins) enable “easy migration” from legacy PIC18 USB devices. In addition to 1.8- to 5-V operation, they feature a Charge Time Measurement Unit (CTMU) for cap-touch sensing, which makes them handy for data logging systems for tasks such as temperature and humidity measurement.

The nine devices in the PIC18F97J94 family are available in 64-, 80-, and 100-pin packages. Each device includes a 60 × 8 LCD controller and also integrates a real-time clock/calendar (RTCC) with battery back-up. Systems such as hand-held scanners and home automation panels are excellent candidates for these devices.

Several interesting designs were on display at the Microchip booth.

  • The M2M PICtail module was used in an SMS texting system.

This SMS text messaging system was featured at Microchip’s Machine-to-Machine (M2M) station. The M2M PICtail module (located on the bottom left) costs around $200.

  • Microchip featured its PIC MCU iPod Accessory Kit in glucose meter design. It was one of several healthcare-related systems that exhibitors displayed at the conference.

The interface can be an iPhone, iPad, or iPod Touch.

Visit for more information.


As most of you know, the entry period for the Renesas RL78 Green Energy Challenge ended on August 31 and the judges are now reviewing the entries. Two particular demos on display at the Renesas booth caught my attention.

  • A lemon powering an RL78 L12 MCU:

Lemon power and the RL78

  • An R8C capacitive touch system:

Cap touch technology is on the minds of countless electrical engineers.

Go to


I was pleased to see a reprint of Mark Pedley’s recent Circuit Cellar article, “eCompass” (August 2012), on display at Freescale’s booth. The article covers the topics of building and calibrating a tilt‐compensating electronic compass.

A Circuit Cellar reprint for attendees

Two of the more interesting projects were:

  • An Xtrinsic sensor demo:

Xtrinsic and e-compass

  • A Tower-based medical suitcase, which included a variety of boards: MED-BPM (a dev board for blood pressure monitor applications), MED-EKG (an aux board for EKG and heart rate monitoring applications), and more.

Tower System-based medical suitcase


I stopped by the STMicro booth for a look at the STM32F3DISCOVERY kit, but I quickly became interested in the Dual Interface EEPROM station. It was the smartphone that caught my attention (again). Like other exhibitors, STMicro had a smartphone-related application on hand.

  • The Dual EEPROMs enable you to access memory via either  wired or RF interfaces. Energy harvesting is the new function STMicro is promoting. According to the documentation, “It also features an energy harvesting and RF status function.”

The Dual Interface EEPROM family has an RF and I2C interface

  • According to STMicro’s website, the DATALOG-M24LR-A PCB (the green board, top left) “features an M24LR64-R Dual Interface EEPROM IC connected to an STM8L101K3 8-bit microcontroller through an I2C bus on one side, and to a 20 mm x 40 mm 13.56 MHz etched RF antenna on the other one side. The STM8L101K3 is also interfaced with an STTS75 temperature sensor and a CR2330 coin cell battery.”


I’m glad I spend a few moments at the Fujitsu booth. We rarely see Circuit Cellar authors using Fujitsu parts, so I wanted to see if there was something you’d find intriguing. Perhaps the following images will pique your interest in Fujitsu technologies.

The FM3 family, which features the ARM Cortext-M3 core, is worth checking out. FM3 connectivity demonstration

Connectivity demo

Check out Fujitsu’s System Memory site and document ion to see if its memory products and solutions suit your needs. Access speed comparison: FRAM vs. SRAM vs. EEPROM

Access speed comparison

The ESC conference site has details about the other exhibitors that had booths in the exhibition hall.







Member Profile: Richard Lord

Richard Lord is an engineer, author, and photographer whose article series on an innovative digital camera controller project will begin in the October issue of Circuit Cellar.  Lord’s Photo-Pal design is an electronic flash-trigger camera controller built around a Microchip Technology PIC16F873. It features four modes of operation: triggered shutter, triggered flash, multiple flash, and time lapse. Now you too can take sound-triggered photos.

The Photo-Pal enables Richard to take amazing photos like this and capture high-speed action.

  • Member Name: Richard H. Lord
  • Location: Durham, NH, United States
  • Education: BS Electrical Engineering 1969, MS Biomedical Engineering, 1971
  • Occupation: Retired electronics hardware design engineer
  • Member Status: Richard said he has subscribed to Circuit Cellar for at least 14 years, maybe longer.
  • Technical Interests: Richard’s interests include photography, model railroading, and microcontroller projects.
  • Most Recent Embedded Tech-Related Purchase: Richard’s most recent purchase was a Microchip Technology dsPIC30F4013 digital signal controller.
  • Current Project: Richard is working on a Microchip PIC16F886-based multipurpose front panel interface controller.
  • Thoughts on the Future of Embedded Technology: “With the ready availability of prepackaged 32-bit processor modules, it’s easy to forget there are many applications where 8-bit controllers are more appropriate”, Richard said. He continued by saying he gets a lot of enjoyment from the challenge of working within the capabilities and constraints of the smaller microcontrollers.