Landing : Athabascau University

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  • Good point, Abyra. We are still a long ways away from understanding conciousness, the issue described by the term 'hard problem of consciousness'[Wiki1] (I quite like the article Will we ever get our heads around...
  • Tyler Lucas published a blog post Getting Started With Circuits, The SparkFun Way March 1, 2017 - 5:08pm
    Getting Started With Circuits, The SparkFun Way
    Tyler Lucas' take on the SIK circuits, part of Assignment 1
  • Tyler Lucas replied on the discussion topic Recommended: Isolate Your USB Connections February 15, 2017 - 10:29am
    Hey Miles. Yep, I messed up and plugged a 19V source into a circuit that wasn't designed for more than 15V. It's not the last time I'm going to make a mistake, however, so it's important to protect what is valuable or time consuming to repair, and...
  • Tyler Lucas replied on the discussion topic Recommended: Isolate Your USB Connections February 9, 2017 - 12:45pm
    Laptop is okay, and USB ports seem to be working. Took it apart and reseated the battery connector. Must have reset something that had been jolted into an un-bootable state through the USB jack. Quite the relief. :)
  • Tyler Lucas replied on the discussion topic Recommended: Isolate Your USB Connections February 8, 2017 - 6:51pm
    USB isolator won't arrive for a few weeks. In the meantime I've started using a name-brand powered USB hub. Here's the external supply I put together to add a fuse and higher voltage tolerance, as well as the flyback diodes in the breadboard. I've...
  • Tyler Lucas replied on the discussion topic Recommended: Isolate Your USB Connections February 8, 2017 - 4:00pm
    Hey Janie, Josh, Richard. I had a servo (MG946R) and external 5V supply driven by 19V (3.16A max) wall-wart, though the Arduino and external supply were not sharing their +5V rails. Blew a capacitor and regulator on the "breadboard power supply"...
  • Tyler Lucas added a new discussion topic Recommended: Isolate Your USB Connections February 7, 2017 - 8:18pm
    Just fried my laptop through the USB programming cable attached to the RedBoard/Arduino when something went wrong on the SparkFun Inventor's Kit breadboard. Could have saved my $2000+ computer with this $15 USB...
  • Tyler Lucas commented on the blog Mini Hot Air Balloon Altitude Control, Or... January 28, 2017 - 5:29pm
    I forgot about your other questions, whoops. I did weigh the Arduino and estimated other componenets: SparkFun RedBoard (Arduino) with all SIK components 173g; balloon envelope 17.3g per square meter; and 50g for the frame, tea light, flame flue,...
  • Tyler Lucas commented on the blog Mini Hot Air Balloon Altitude Control, Or... January 27, 2017 - 1:14pm
    Hey Josh, good questions and points. You're right, there are differences in heating with an open flame and a mostly radiant source like a light bulb. The flame heats the air immediately surrounding it (and the CO2 released by its own chemical...
  • Tyler Lucas published a blog post Sensors! January 24, 2017 - 3:42pm
    Sensors!
    An attempt to make a sensor from every component in the SparkFun Inventor's Kit
  • This came about while answering the very first question in the course: (Unit 1: Introduction to Robotics) define the term robot and provide a brief history of robots and robotics. While the book The Robotics Primer has a definition, I chose to dig a...
  • COMP444 Assignment "0" - First Steps With SparkFun Inventor's Kit
    I blab about where I roam for information and inspiration, and jump into my SIK and play with the first circuit example.
  • Tyler Lucas published a blog post Mini Hot Air Balloon Altitude Control, Or... October 18, 2016 - 1:26pm
    Mini Hot Air Balloon Altitude Control, Or...
    ... Or: How I Decided To Go Back To The Drawing Board, A Top-Down Project Assessment
    Comments
    • I really enjoyed reading this thought process; it is (was) a very creative and clever project proposal. My initial thought was, "controlling a combustible on a small scale...this guy has gone mad in all the right ways!", but then I did see your renewed approach using a lightbulb, or any other heating source, which I thought was clever. I wonder though, ignoring the lift-constraints and specific heat conversions, if you used a lighbulb, or heating element other than a combustible, would you achieve the same lift? I don't know anything about thermodynamics, but I am making the assumption that a combustible produces a more directional heat (eg. up), while other heating sources would produce a more radial heat. Without the upward "drive" created by a combustible, would you need more heat? Or would it simply take longer to achieve the lift?

      Out of curiosity, did you weigh the Arduino and potential battery packs required? Do you think it is possible, even at large scale to produce a hot-air balloon using batteries as the power source? For instance, I'm guessing there is an equation for a lithium-ion battery that can provide available power output based on weight (roughly)? For example: (made up numbers here) a 500g lithium-ion batter is capable of producing 2000mAh of power, 2000mAh power can be converted into X-amount of heat using my heat source, which can achieve a maximum lift of 400g. I am mostly curious if the relationship is linear in that you would never be able to achieve enough lift regardless of heat source since the batteries output is never enough to overcome the weight of itself.

      Also, what were you going to use as the altitude sensor? Does such a thing exist, or were you going to program a sonar sensor to compute the distance and adjust accordingly?

      This is a great thought-provoking proposal. As you had mentioned, it is too bad you couldn't get it off the ground!

      Josh Weston January 26, 2017 - 8:05am

    • Hey Josh, good questions and points. You're right, there are differences in heating with an open flame and a mostly radiant source like a light bulb.

      The flame heats the air immediately surrounding it (and the CO2 released by its own chemical reaction) in a process called conduction or diffusion, which then flows up due to the very buouncy forces we are investigating in a process called advection, then swirls around a bit in a chaotic fashion. Together, this is called natural convection. The flame also radiates heat with photons streaming out and being absorbed partially by the air it encounters and primarily by the balloon wall, at which point the heat is diffused or reflected back into the air inside the balloon, spread through to the outside of the balloon wall, and outside of the balloon.

      The light bulb is a hot filament that does the same thing as the flame but in different proportions -- there is more radiation being emitted than convective. This means there is less "swirling" or mixing than with the flame.

      Convection heats the air in the balloon more effectively than radiation, just like a convection oven cooks more evenly than those without forced air. Radiation from a light bulb heats objects better than air as it emits mostly infrared, which is not well absorbed by air (see Wikipedia: Infrared Window). This means it heats the surface of the bulb and the balloon material first, then the glass bulb and the material heats the air. Reflective material helps reflect heat back into the balloon. In the end, both methods heat the air in the balloon, but convection is more efficient.

      The lifting effect of the initial upward draft from an open flame is cancelled out in a closed system (the rising air mass has an equal portion of lowering air), but it does allow placing the heating element below the heated chamber while maintaining high heat transfer ratios compared to the amount of heat that would escape with a radiative source in the same location.

      Another practical consideration you mention is that a light bulb would need a lot of electrical energy, namely batteries. The maximum energy density of available batteries is around 0.5 kWh/kg or 1.2 kWh/L. By comparison, that of paraffin wax is around 12 kWh/kg (42 kJ/g) or 6.1 kWh/L, at least five times more energy dense. Without taking into account system efficiencies, a battery operated heater would require at least 5 times more fuel mass (batteries) than a paraffin wax heater (candle). Batteries could still be used, however, with a sufficiently small time scale (batteries die) and a sufficiently large volume of air. Although fuel weight (and volume) to energy output is linear, including batteries or paraffin wax, air volume to material weights is not, so scaling up the size does work. The only limiter is fuel suitability -- can you release and spread the energy quickly enough to heat the air? I leave this up to the hot air balloon pilots... :)

      Cheers

      Tyler Lucas January 27, 2017 - 1:14pm

    • I forgot about your other questions, whoops.

      I did weigh the Arduino and estimated other componenets: SparkFun RedBoard (Arduino) with all SIK components 173g; balloon envelope 17.3g per square meter; and 50g for the frame, tea light, flame flue, and battery (I hadn't planned on using the battery to heat the air, only to power the microcontroller and flue). This was a high estimate for total weight.

      Altitude sensor would have indeed been a sonar sensor.

      Tyler Lucas January 28, 2017 - 5:29pm