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Building an Open Source "Clicker"?
fieldtest asks: "Most Slashdot readers have read about "clickers", remote control style devices that students use to wirelessly answer a teacher's questions. Unfortunately, as a college student, I have had less than stellar experiences with these clickers. I hear complaints from my professors and fellow students often as well. So, I want to build an open source clicker system for all universities to use. I believe that this is a prime opportunity to show how powerful free software can be.
So, what do the talented people of Slashdot recommend?"
"The problem is this: a clicker system requires...clickers. What I need are remote controls that have a minimum of 6 buttons (for users to select options with). The sticking point comes when a button is pressed -- the remote must send the option choice, as well as a unique ID specific to the remote, so the clicker software can distinguish between different students.
I've experimented and Googled around. I've tried standard TV remote controls combined with an USB-UIRT receiver, but the range was too low. Googling shows some interesting programmable remotes, but they're far too expensive ($100+) to have each user purchase one.
How should I go about building the perfect clicker and receiver system? Any suggestion is welcome, from IR to radio, from Bluetooth to ZigBee based communications. Recommend a commercial product, or a do it yourself solution. Please also recommend a receiver device, and a way to connect it to a computer. Also, if you recommend that I just build a custom circuit board for the remote control, please give some references and examples of how it should be implemented."
I've experimented and Googled around. I've tried standard TV remote controls combined with an USB-UIRT receiver, but the range was too low. Googling shows some interesting programmable remotes, but they're far too expensive ($100+) to have each user purchase one.
How should I go about building the perfect clicker and receiver system? Any suggestion is welcome, from IR to radio, from Bluetooth to ZigBee based communications. Recommend a commercial product, or a do it yourself solution. Please also recommend a receiver device, and a way to connect it to a computer. Also, if you recommend that I just build a custom circuit board for the remote control, please give some references and examples of how it should be implemented."
I think you're missing the point here. Most people who have problems with clickers won't find those problems disappearing with an "open-source" clicker. Their problems are either with the hardware (which it seems you are not trying to improve), or with the whole concept of using clickers.
Personally, as an educator, I would find clickers to be a nuisance, and wouldn't find them useful anyway. It is far more effective to try to interact with the students and understand where their learning is at, individually, then tailor my teaching to whatever common problems or such need the most attention.
Put the room on springs.
Put a giant bar magnet with the north pole facing down in the ceiling.
Give each student a bar magnet. Mark the south pole "yes" and the north pole "no".
Students hold their magnets in the air to indicate the answer.
If the room moves up, the majority of the students chose "yes". If it moves down, the majority of the students chose "no". The more it moves, the more the students are in agreement.
Best of all, the batteries will never die.
Unless you drop the answer sticks.
Do daemons dream of electric sleep()?
Q: "How do I get the smart slashdot folks to help me with my class project?"
A: "Tell them that I'm gonna make it Open Source!"
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CY7C601xx
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* Programm
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry
For those 100 or 200 level classes with 200+ people in them, one might argue that it would be beneficial to maintain order. But the reality of the situation is that you'd have to give out clickers to every student, then train the professors how to use them. And seriously, folks, most professors aren't going to give a damn about learning to use these, especially those older ones with tenure who were born before Christ walked the earth. So they're most likely going to ignore them anyway. The other disadvantage is that these things would break down, and probably frequently. Students themselves wouldn't know how they work (properly, being the key word here). When they think they know how it works, the darn thing will break, and have to get fixed. IT departments are just going to love these things! LOL
You could use USB for the interface back to a piece of host software on a regular computer. There are lots of cheap microcontrollers with USB interfaces built in, and they even come with reference firmware and drivers. USB is an incredibly easy bus from a hardware circuit perspective too.
Combine that with pcb123.com and a couple hundred dollars for boards and parts, and you've got your clickers. The only hard part will be finding some kind of plastic case to put them in that will be durable enough for classroom use. You can save money by not soldering the USB connector onto all the boards.
laser pointers, 4 large areas above the boards: A, B, C, D. A&D substitute for yes/no.
Have people point to the area they want. roughly count the dots.
Anonymous too: it's hard to tell in a room of 100 students where 1 in patricular is pointing to.
Of course, this could also be used as a mass weapon against a professor who insists on lecturing until the very last minute of class, and _then_ giving out the assignment for next class.
"Piter, too, is dead."
Raise your hand?
People don't like to feel stupid, especially in front of their peers. If a professor is trying to find out if her students know something and asks for hands, you get three different groups
Clickers let the professor get high response rate with anonymity. There's a lot of hate on /. for these things, but used properly (and I've seen it done many times) they're a great tool
"Seven Deadly Sins? I thought it was a to-do list!"
1. Professors won't go for it. Cell phones are already enough of a problem in the classroom. The last thing most professors want to do is encourage people to bring them to class and more importantly, if they must be brought to class, they'd rather not have students leaving them on (as a college student who has had a lecture course of 300 students interrupted on multiple occassions by one or two idiots who leaves their phone with who-knows-what ringtone on, believe me, I know).
2. Students won't go for it. Contrary to popular belief, not all students have or want cell phones. I don't own one and plan on avoiding owning one as long as possible (hopefully until whoever I work for buys me one and pays for it). I'd rather not have to pay yet more money to go to school just so I can answer quizes - books cost enough, thank you very much.
The problem with a unique ID for the clicker is that you could later identify who had which clicker, meaning that the answers would not truly be anonymous.
Instead, I would have a button on the clicker with a label like "begin session" which would cause the device to generate a UUID for the session.
Alternatively you may want to take each measure independently in which case you can create the UUID for each button press.
It is preferred that you have a MAC address to create a UUID, but you don' t necessarily have to have one. Some classes of UUIDs do not require a MAC. Alternatively, the device could retrieve a UUID via a transaction when it is activated.
If I were doing this, I would probably write a version of the app for Windows, Mac, Linux, Palm, WinCE, and Symbian.
On the more capable devices, you could make such a clicker pretty sophisticated. For example, it could show the text of the question and whether you have already answered it or not.
I would probably have a Mac/Windows/Linux PC application recording the data for each question. I'd probably set it up to be fed into SPSS or whatever.
Avoid Missing Ball for High Score
Here at UC Berkeley most students hate these clickers (called 'PRS' here, for personal response system or some shit like that). It is so superficial. A professor throws on some multiple choice question, and people hit a button to answer it and get participation credit. Is this the second grade or something? What the hell is participation credit for - in colleges we don't need that kind of bullshit. If people don't want to pay attention to lectures, that is their choice - most of the time lectures are useless anyways. Not only that, it wastes $45 on each student's part.
The best solution is to not have any such system and simply DO example problems in lecture. The thing that college lectures lack is not something captivating (like hitting the button on a remote is actually captivating...) or innovative, but BETTER LECTURES. Period. Lecturers tend to go over things in too much of an 'overview' format (at least in the science/tech classes) and avoid doing actual example problems that might help us LEARN.
Instead of throwing materials and problems at students and saying 'Here go study and come take my test later', lecturers should try to teach the students legitimately and AIM to improving their testing performance...right now, all it feels like is that I am paying 20k a year for taking a few tests. A f***ing remote control won't solve this issue of boring, shitty lectures.
Alright.
First, a normal infrared remote won't work. You'll need a custom programmed microcontroller remote and a receiver to handle such. In order for the receiver to detect all the remote's answers (given a one way system) each remote, when the button is pressed, would send its message, pause a random amount of time, send again, pause random again, etc. This would go on for a second or so during and after the button press so the receiver has a chance to catch it in the midst of all the other remotes sending their data. The data burst would have to be *very* short to increase the bandwidth and decrease the collision rate.
A one-way RF system would be very similar.
If you do a two way radio, there are a few more options. Ideally you'd do a two-way network (such as zigbee) since it would be very expandable - it could accept a variety of clickers from the simple credit card remote to the full keyboard and display.
A simple 2.4GHz custom network could be designed using Nordic Semiconductor's nrf series of chips. The nRF24E1 chip would be perfect - includes microcontroller, 2.4GHz transceiver, and is very low power.
-Adam
Wrong.
This is for students who are in a lecture hall with over 100 other students. There is simply no way the professor can give individual attention to each student. Because of this, clickers are the easiest way for a professor to get a feel for whether or not he is effectively getting his point across.
If 90% of the class answers a question correctly, the professor can feel somewhat confident moving the lesson forward. If only 20% of the class can answer correctly, he knows to spend some more time in that area of the lesson.
The clickers have absolutely nothing to do with being social or anti-social. They are a tool for helping professors figure out whether they are getting their ideas across, instead of just staring into a sea of blank faces.
Pretty much every phone has blue tooth OR an IR POrt. Just get a receiver.
Sorry, but the point of education isn't to socialize you. It's to teach.
I think these devices are great. I used them in classes in highschool. They greatly improve the efficiency of a classroom environment. They can enable all students to learn, via a distributed Socratic method, as though each had a personal tutor. This type of teaching is unparalleled in efficiency and efficacy. Schools in the near future will have to use them to maintain standards and keep down costs.
Let me give you a personal example. For the year that I attended college, I had a Calculus class. For the most part, the object of this class was to have us memorize as many different estimation methods as possible. I think it was called Calc II. There were around 40 students.
Every class period consisted of the same general routine. The professor would have us turn to a new chapter in our 50 lb book. He would begin to explain whatever new concept he hoped to teach in that hour long class. After about three minutes of explanation, a girl at the back of the class would raise her hand and ask some inane question, usually pertaining to whatever was taught in the last class period. Being the nice helpful teacher that he was, the professor would then spend anywhere from fifteen to thirty minutes explaining some concept that most of the class understood to this particular student, almost completely ignoring the day's lesson. At most, the professor usually got about half of each lesson completed before the class was over.
In effect, this one (poor) student got a half hour worth of private tutoring out of each class period. The other 39 students in the class got to figure out the lesson for themselves on their own time, before the next class period, and attempt the homework from their own self-teachings.
Had the professor used some of these devices, or at least a little common sense, he would have been able to judge the rate at which each student was understanding his lessons. Those who didn't keep up could be tutored separately, outside of class. Instead of charging ahead into new, more complex concepts, he could have spent more time on the things he was doing a poor job of explaining. Instead, the class snowballed into a giant clusterfuck of confusion and waste for all involved.
This was an expensive, small private school, yet, apparently, was run by idiots, and happily catered to idiot students.
I was on full academic scholarship as a National Merit Finalist yet, needless to say, I flunked right out. And I have no intention of going back. Tuition rates have doubled. The school is still run by (and filled with) the same idiots. I can seriously get a better education for free, on the damn internet, than I can wasting my time there.
I went to college for an education, not for a social experience, not for psychological evaluation, and not to waste my time. And while, technically, I failed college, in reality college failed me. College failed to provide me with an environment in which I could learn. By the rising tuition rates all over the country, most colleges are failing just as badly as mine was. I didn't need to pay more to have psychologists tell me what I was doing wrong. I needed a professor that would teach instead of waste my time.
So, in conclusion, why don't you just take your ridiculous preconceived notions, and your "let them have psychologists" attitude, and cram them up your ass.
"I assumed blithely that there were no elves out there in the darkness"