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lack of focus

Deskbot Part 1, Architecture

It's been a while since I've done any robotics, so let's make that happen. When designing an autonomous system, it's critical to have clear objectives so that the requirements for end effectors, sensory inputs, and processing resources can be achieved inside your cost and time budgets. Instead of that, let's try to settle an office debate: what are the kinematics of a robotic platform positioned by 3 control rods?

Then, we'll put eyes on it. And it needs to fit on my desk; my apartment is not very large.

VFR Flight Minimums

While studying for the Private Pilot Knowledge (Written) Test, I had a hard time memorizing the rules governing the minimum requirements for VFR in the difference airspaces. A fellow student pilot found this sketch by R. Tyler Croy. I really like how it distilled the rules into something small enough to jot down at the beginning of the exam. I drew up a very similar chart, correcting for 1200 AGL rather than MSL.

Simple Stepper Motor Control with Raspberry Pi

Stepper motors are a type of brushless DC motor that can be controlled so that they advance a fixed step size. Additionally, they provide a strong holding torque. This can make them useful in applications where you want to rotate the motor precisely without employing encoders. When prototyping, I like to use development boards that can be transferred to a custom PCB easily. This gives me a clear path if I want to move the design from the Protoboard to something more polished.

Animated Bugs with Blender and Tricaster

The local public access station produces a weekly news/entertainment program called The Local Live. The format features a live interview segment where community calls, emails, and tweets are taken on the air. To keep the contact information onscreen throughout the entire segment, I wanted to animate the contact info into a graphics bug. The station uses a Newtek Toaster Tricaster 860. By dedicating a video playback DDR to a DSK channel, we can overlay videos with alpha.

Smoothing Rates of Change

This is probably something that would have been obvious to everyone else, but stumped me for a bit when I came across it the other day. I was looking at the rate of change of a sequence, and my smoothing algorithm wasn’t doing any better than just subtracting two points in the sequence farther apart. In fact, the results were identical. This won’t be particularly rigorous, but I believe the concept is valid.

Replacing the A/C Blower Resistor on a 2009 Ford Escape

The A/C system of the Ford Escape has a resistive sensing element used regulate the blower motor. If you find that the A/C blows air on some fan speeds but not others, it is likely that the blower motor resistor has burned out or otherwise failed. On my 2009 Escape, the blower motor would run in positions 3 and 4, but not 1 or 2. Based on other reports online, failing for the low speed settings seems to be the most common symptom.