Project: rectifier box

Hello :slight_smile:

I have a project but need some help but also some guidance. As part of a group we were wondering how to start this so does anyone have ideas. I’ve attached the document. I would really appreciate it thanks!!!

Objective
The Miami Dade County Public School (MDCPS) system is interesting in developing an educational tool to teach rectifier circuits to magnet high school technology students. While they plan to initially pilot the program in a few classes, if successful, the intent would be to expand this project to thousands of classrooms across the country. The school system is currently soliciting prototypes from private companies, and your boss has assigned your team to the task.

While the initial bid is only worth a few thousand dollars to your company; if selected and your design proves successful – this project could result in a no-contest bid to create these boxes for the entire country which would result in hundreds of thousands of dollars for your company.

Project Requirements
The administrators who initiated the project are not technically inclined, so the specifications they have provided are very general and minimalistic. They are expecting the competing companies to take their specifications and come back with a working prototype and manual that will wow them. The minimal requirements for the project are:

  1. The final prototype must be a professionally packaged and fully soldered. It must also provide no electrical hazard and be durable enough to take a beating from high school students.

  2. The school district would prefer it if an external power supply were not necessary. You can assume that the classroom your box will be deployed in has a standard function generator (input source) and digital oscilloscope (output source). If you do use an external power supply, it must be a professionally UL certified (i.e. if you are taking power from the wall, you must do it with a purchased adapter that is fused and simply plugs into your device). Safety is of the utmost concern for the school district.

  3. A manual that fully describes every function that the box performs. This is one of the most important aspects of the project. The manual must detail at a minimum:

a. The parts (with part numbers) that were used
b. The absolute maximum/minimum amplitudes, frequencies, etc for each function given the parts that you used
c. Complete Schematics of the system
d. A sample set of experiments the students can perform using your box with complete simulation results. You can use the equipment in our lab to get a rough approximation of the output capabilities of the function generator, but remember that although you are guaranteed that the school will have a function generator; it may not have the exact same capabilities of the one in our lab. Thus, your sample experiment should take this into account.
Rectifier Box Requirements
The school district is expecting you to use your technical creativity to impress them; however they have provided you a simple example of what they are looking for and come up with a set of minimum rectifications that your device must be able to accomplish:

The box must, at a minimum, perform the following functions:

F1. Straight pass-through
F2. Half-Wave rectification
F3. Full-Wave Rectification
F4. DC Output
F5. (A fifth function that you design)

Please note that the above design is simply an example, and you can feel free to improve upon or design the box in a different manner – but the functionality must be completed.

and where is it?

allan

sorry was having trouble uploading it

(deleted)

All that for 2 diodes, a lowpass RC filter for DC output, and a couple of switches?

spycatcher2k:
Not really anything to do with Arduino, is it? Every function can be realized with discrete components.

I guess that's why I'm asking for additional help. The objective is to encouraged us to go beyond but I"m not sure exactly how to start

All that for 2 diodes, a lowpass RC filter for DC output, and a couple of switches?

Try this
http://www.snapcircuits.net/

The snapcircuits remind me of my first DIY experimental system, using patent fasteners :slight_smile:

Am I missing anything? How many of these would you want?

@CrossRoads: Your bipolar “rectifier” is very creative, but it won’t work :wink:
A full bridge rectifier (4 diodes) requires to switch the outputs as well.

A voltage doubler (half bridge) could be added, for demonstration purposes. It also requires to switch the outputs.

A totally enclosed box with a rotary switch on top will meet the safety and functionality requirements but it doesn't teach anything. It's just a black box.

4 diodes and a breadboard (or something breadboard-like) will be much more educational but there's a 100% chance one of the students will try to put his or her tongue across the 12V terminals.

So a transformer & bridge rectifier then?

Is grounding with the transformer like that going to be a problem? I don't think I ever fullwave rectified a signal where I didn't use an op-amp, and even then it was only for an envelope follower to catch the peak of a signal.

I agree, having a bow where some wires could be moved around to mix things up would be better, like the old Radio Shack Learning Lab, with the spring terminals for connecting things up.

This way they are limited to what can be demo'd, but at least nothing is walking off between classes.
Different boxes can be made up to demo different concepts I suppose. At some point wallwarts would be needed for powering op amps or logic ICs.

Okay so whats the best way to go about this?

Don't know, your call.

  1. Box as originally envisioned, limited functionality, no parts to get lost or walk off.
  2. Something with more installed parts, jumper wires for kids to connect things up in some manner. Think something like the Radio Shack learning kit.
  3. Something with ultimate flexibility, all loose parts, connect up as needed. Think an Arduino Starter kit.
    Forum member Terry King at www.yourduino.com has #3 in various assortments and offers educational discounts.
    If you're not thinking microcontroller based, he could likely compile a basic electronic set of stuff too.

All will need some kind of documentation/learning books to help teachers out, yourduino.com also has a section on that kind of stuff. There are also books on basic electronics, or you could work with an author to come up with specific stuff for the material you end up with.