Need help: Ideas for basic ATTiny85 projects for kids  - Page 1
Forum section: electronics / general

author: Mr J
author_rank: Regular Contributor
timestamp: July 18, 2013, 03:50:21 am
content: Hi guys I'm looking for some help coming up with ideas for basic ATTiny85 projects for kids ages 12-14. I am a teacher at a vocational high school and we just started up a “Engineering Academy” to get high school kids interested in electronics, drafting and precision machine technology, the engineering clusters.Here are some ideas (with links) I've got working so farhttp://www.n1ir.com/2013/07/attiny85-basic-combo-lock.htmlhttp://www.n1ir.com/2013/07/police-style-strobe-light-attiny85.html(like Federal Signal Type)http://www.n1ir.com/2013/06/simple-dice-project.htmlhttp://www.n1ir.com/2013/06/prototype-line-following-robot.html(Capstone project with Arduino)TV-BE-Gone (via Adafruit)Strobe using white LEDSome other ideas but haven't got working yet,IR Remote JammerTraffic Light, fully functional with multiple ATTiny Master/Slave (almost got this one working)password keeper (like Frank Zhao USB Card ie: push caps lock three time output a string)USB caps locker prankI try to get project completely working and PCB designed and tested before students ever see the project. The idea is to keep price down to about $2-$10 per unit cost. We see about 120 kids in one year with about 72 hour semester (lab, hands on time). What ever they build they get to keep at no charge to the student (there are no lab fees). The cost is paid by the department so the more optimized the price the more we can do. I do have a bunch of analog projects as well finished and in the can.Our capability we have in our shop:Three T-Tech 5000 PCB millsLPKF s63http://www.n1ir.com/2013/06/new-toy-lpkf-s63.htmlStratasys - Dimension 3D Printers, Rapid Prototyping SystemCreaform EXAscan Handyscan 3D handheld 3D ScannerCrap load of parts (all logged on to ecdb.net)http://www.n1ir.com/2013/05/parts-and-more-parts.htmlAny help would be appreciated,CJ, N1IR

author: ElectroIrradiator
author_rank: Frequent Contributor
timestamp: July 18, 2013, 03:18:07 pm
content: Hi J.,Do you have any guidelines for the complexity of the software/programs for the AVR? Am somewhat short on time today, yet based on some of my previous work experience I may have a slightly baffling idea for you. It might be both educational and entertaining for your students. However, I am somewhat reluctant to reveal the idea or even claim it can be done, before I have actually done it.The issue is that the software for the AVR would emphaticallynotbe trivial to write or understand, though the operation of the completed widget is. I wouldn't mind letting you or others have a go at it, of course, but then I need to write a detailed description of the depth of my insanity.The idea started out as a bit of a dare among friends, and I have sort of been looking for a good excuse to actually build a proof of concept.

author: fcb
author_rank: Super Contributor
timestamp: July 18, 2013, 03:57:46 pm
content: Small robot.Use 2x small mabuchi type tin can motors ($0.5 each) and print a simple gearbox and mount (body of robot?), make it a linbe follower or make them 'fight' each other.

author: nctnico
author_rank: Super Contributor
timestamp: July 18, 2013, 09:07:12 pm
content: I'd slab embedded LUA on a board and let the kids program with that. Chances are some already know Lua from coding in online games.One of the ideas in the back of my mind is to design a low-cost I/O board (like 32 or 64 channels analog) and run Lua on it so it can run standalone tasks or communicate with a PC. Ideally the outputs should be able to drive a small relay or DC motor.

author: Mr J
author_rank: Regular Contributor
timestamp: July 22, 2013, 04:30:34 pm
content: Awsom just checked out the embedded LUA athttp://wiki.eluaproject.net/FrontPage.thanks nctnico, I may use this for AVR32 stuff for my upperclassmen (12th grade) after the arduino block.

author: Mr J
author_rank: Regular Contributor
timestamp: July 22, 2013, 04:47:52 pm
content: To answer ElectroIrradiator, here are the guidlines for the students found athttp://www.doe.mass.edu/cte/frameworks/engineeringtech.pdf2.Z Apply microprocessors.2.Z.01 Formulate a flow chart to correctly apply basic programming concepts.2.Z.02 Design and create a program to evaluate data and make decisions using external digital and analog sensors.2.Z.03 Create an interface that inspects, evaluates, and manages program parameters during the operation of the program.The student comming into the program are very young about age 13 with no skill sets, they are just learing to solder, ohms law, componets, etc.The plan is to go over how to program (burn) an AVR usinging something like avrdude or the Arduino IDE, know about hex files, make files, C, config bits. How to change a given program ie swap pins, change delays and how to debug, etc.

author: ElectroIrradiator
author_rank: Frequent Contributor
timestamp: July 22, 2013, 07:03:58 pm
content: OK, then my first idea clearly won't work, though my second one might, depending on what you have hidden in those storage drawers and how skilled/motivated the student is.Make a simple 2 digit 0.0-9.9V digital voltmeter, would even be useful later if done right. You'd need two 7 segment LED displays, or 30 individual LEDs, plus a pair of 74HC595 (or similar) 8 bit shift registers.Simple voltage divider on input, 200Kohm or so in total. May have to tweak the lower resistor in parallel with the A/D input to account for load of A/D, perhaps talk to students about calibration and accuracy here?Pair of diodes at the A/D input pin for over-voltage/reverse polarity protection, small cap in same location for a bit of noise immunity.Output shift registers drives the LEDs directly through current limiting resistors. Either use 7 segments, or 2 LEDs in series for each segment plus decimal point. A 74HC595 can sink or source up to 70mA through Vcc or GND, so you can use either CA or CC displays, depending on what is available. I'd start with 8 mA per segment/chain, test. 2 LEDs in series on a 5V supply may be tight, but should be doable, just, with a CMOS driver plus small current limiter.The input can be made more fancy to allow it to detect reverse polarity, which the display could show in a suitable fashion, '--'. Would give opportunity to talk about the potential problems with common ground etc.On a 10 bit A/D you could even 'autoscale' the 0-1V range for 10mV resolution as a bonus software feature, movable decimal point and all, if the student gets the basic functionality up and running too quickly. Questionable accuracy perhaps, but fun extra.Pin budget: 3 for control of the shift registers, 1 for voltage input, 1 optional for reverse polarity detection. Still leaves RESET for debugging and reprogramming. Could also use an AVR with a higher pin count for this project, if they are available. Would save the shift registers, so may be a more economical solution.