It says there is one complete and one active. I don't know why. This is a copy/paste of the summary.
Please let me know if you have any questions about what i said. I didn't grade the sections or worry about the writing style quality (which was good, BTW).
Howard
A Presentation and justification of the problem
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This is fine as a summary. The statistics certainly speak to the need for a better way of getting evidence.
B Documentation and analysis of prior solution attempts
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I'd suggest you include a survey of some of the commercial tracking cameras available. There seem to be quite a few, like this one:
http://www.ezwatch.com/ez-track-dome.html (whose site you refer to elsewhere) that are using the imagery from the video to determine motion and identify objects. As you noted, these are very expensive but it would be worth discussing how they work and what the differences are between these are your design.
C Presentation and justification of solution design requirements
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This shows good thought into the issues and i like that one of your goals is to make it inexpensive. Whether you hit that price point or not (I don't expect anywhere near the $40 mark) it should be far cheaper than the $1000+ that the commercial solutions seem to offer.
D Design concept generation, analysis, and selection
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There are no comments for this element review.
E Application of STEM principles and practices
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Smart to turn the sensors sideways! That does give you a more precise positioning system at the expense of adding perhaps an extra sensor. That's still a good tradeoff if it helps catch a burglar.
Your explanation of the science and tech here is both sound and easy for others to understand.
F Consideration of design viability
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You do seem to have done your research on parts & availability. You'll find that the direct purchase from China is rather difficult so I'd not count on the $20 version - at least not right away.
G Construction of a testable prototype
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The sensor arrangement and support/baffle system looks fine. I can't say whether it will work or not looking at it, but that's what your testing will confirm. It's certainly a promising design.
I'm concerned about your camera mount. If the center of gravity of the camera is not directly over the servo shaft, you'll be putting a torque on the shaft which will make it harder for the shaft to turn, reduce the load capacity and accelerate the wear on the servo. That's why I had suggested a lazy susan sort of system but yours might be helped by simply adding some small support wheels holding up the edges of the platform. Three or four small casters pushing up on the bottom of the platform, arranged 120 or 90 degrees apart would let the camera weight be borne by the casters while the servo only had to handle the rotation.
The code also seems to identify the sensor area with new motion and then snap the camera to that sector. Ignoring the obvious - that servos tend to make noise which will attract the thief's attention - the camera motion will be jerky and make the video harder to follow. You may also run into a situation where the sensors cause the code to rapidly switch back and forth between two sectors. Consider changing your algorithm so that if one sensor is now more interesting than the one to one side of it, move the servo slowly (perhaps incrementally changing from one position to the other) and think about some algorithm which prevents it from just oscillating back and forth. Conceptually what you've done looks good but I'd be curious if the video is hard to watch as the camera snaps from position to position.
Do think about ways of muffling the noise. Can you add some foam or insulation in the area beneath the platform to help muffle the servo noises?
H Prototype testing and data collection plan
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A good plan. Please consider the previous suggestion of adding supports around the servo with casters so that the camera weight isn't twisting the servo shaft. Also, what happens if multiple bad guys start walking around the room at the same time?
I Testing, data collection and analysis
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There are no comments for this element review.
J Documentation of external evaluation
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There are no comments for this element review.
K Reflection on the design project
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There are no comments for this element review.
L Presentation of designer's recommendations
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There are no comments for this element review.
M Presentation of the project portfolio
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There are no comments for this element review.
N Writing like an Engineer
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There are no comments for this element review.
