Regarding Charles Gantt's "Design Challenge Summary, Week Ending July 18th" article and the Picorder project progress:
I apologize for the lack of recent pictures of the Picorder to all of element14, challengers, readers and followers. However, previously I wrote that I'm removing the CO2 and alcohol sensors due to their excessive power requirements and replacing them with other types of less power demands which requires redesign of the Picorder. This has been ongoing since that posting.
As my last posting stated, I've had to undergo some major redesign of the Picorders sensors, type and quantity. From the time I posted the videos, photo galleries and demos of some of the sensors, the overall physical characteristics of the unit have not changed.
The major changes are with getting the scripting to function correctly. The sensor outputs to the GPIO inputs are basically similar in operation regardless of the sensor type for the sensor modules I'm working with.
There are three basic type inputs to the raspberry pi as it pertains to the GPIO's.
First we have a standard analog input which accepts a typical analog signal without regard to frequency or amplitude (except that which are minimum/maximum thresholds for recognition by the pi).
Secondly, there is a digital signal which can be recognized by the GPIO pins. The digital signal is in the format of binary 1's and 0's and functions as a continuous data stream of transitions per time period. Last but not least is a PWM signal recognized by the pi. This PWM (Pulse Width Modulation) signal as its name implies, is a digital signal of varying time durations (widths) of the binary 1's 
and 0's 
between transitions. The varying timing and transitional occurrences’ differentiates this format from the digital signal.
These three signal formats allow the Picorder to interpret its GPIO input and respond (or output) very differently. The DHT11 temperature sensor allows the Picorder to interpret the signal constantly, and produces continues change reading of temperature and humidity while the flame sensor supplies a digital (toggle) signal of either ON or OFF to the pi until the sensor reads a change. With the PWM signal to the pi, an on/off signal allows the pi to perform a specific function for a fixed or variable duration (time period). Incorporating these three variations of signaling formats into the script is challenging.
Unbeknownst to the readers and followers of the “sci fi your pi” challenge, my Picorder, and element14 this challenge has been my introduction to programming languages in general, specifically Python, Bash, and others which I am working through to learn and understand given the time limit of the challenge. Exposure in these areas is limited for me since I seem to have been more hardware oriented than software over the years.
Moving forward; I've torn down the Picorder to rebuild it with some new sensors all the while working on the scripting as I go and taking a line-by-line approach to get the programming to work. As originally outlined at the beginning of the challenge, my intent with the Picorder needs to be a self-contained autonomous sensing device with consistent and continuous readouts for its user to address conditions hazardous or of interest to human life. In unexplored environments as was typical of Star Trek: TOS landing party, such readings could alert the crew to other life forms and unexpected dangers while conducting planetary exploration.
I am currently replacing the sensors mentioned above and hope to post some photos not later than tomorrow. They should include the disassembly of the old and installation of the new sensors. I have a circuit diagram I drew last week (with the CO2 and alcohol sensors) and will draw a second one with the replacement sensors and post them both with the new photos. As has happened already with other contestants of this challenge, I’ve encountered some unexpected results and obstacles to overcome. But then that’s what is to be expected with design, engineering, and prototyping. The 90/10 perspiration/inspiration factor wins out every time! More to follow…