Science Buddies: "Ask an Expert"

hi.i need an idea about how to connect the voice recognition circuit to the RF transmitter in the remote control for the car.but if theres a faster,cheaper and easier way than using that curcuit that would be great!please i need it soon.thanks a lot!

Although this is a very simple concept, it is an extraordinarily complex concept to put into reality. That's why we don't drive voice controlled cars today.

This project warrants quite a bit of basic research. You need to know how voice recognition systems work. There are numerous approaches to this, all with varying kinds of output. Once you understand the types of output you can get from voice recognition systems, then you need to understand RF controllers and what they need for inputs. You'll then need to learn how to convert the output of the voice recognition system to something the RF controller can understand. Once you know all this, you'll be able to build the devices necessary to make all this happen.

For your basic research you might consider sources such as these:

http://www.robotshop.com/forum/showthre ... ed-Vehicle

http://www.nxtprograms.com/voice_car/steps.html

http://www.ece.gatech.edu/academic/cour ... oposal.pdf

Good luck.

i have the voice recognition circuit and i have already programmed it(go,stop....)but i need to know how to connect it to the remote(RF transmitter).i also don't know what type of wires i should use .thanks!

Could you please provide enough details that we'd have something to work with, Gijoe1442? Without circuit diagrams, specifications, model numbers and the like, we have nothing to work with. As for wire, what is the wire used for? For most applications ordinary hookup wire (of suitable size for the current) can be used. Very high currents or frequencies > a few MHz require special types of transmission systems,

Model
Speech Recognition Circuit :SR-07
Circuit Memory :8k X 8 Static RAM
Word Length
for:40 words 0.96 seconds
20 words 1.92 seconds.
thanks!

You say

>Speech Recognition Circuit :SR-07

Who is the manufacturer? Is there a data sheet? If not, could you provide a circuit diagram plus info on the I/O format and output drive levels, eg TTL, LVDS, ...

How about the device receiving the output(s) of the SR-07? I'll need the same information. And also the requirements on input timing including details of how the link (SR-07 to RC device) is clocked.

The heart of the circuit is the HM2007 speech recognition integrated circuit. The chip provides the options of recognizing either forty .96 second words or twenty 1.92 second words. This circuit allows the user to choose either the .96 second word length (40 word vocabulary) or the 1.92 second word length (20 word vocabulary). For memory the circuit uses an 8K X 8 static RAM. Manufacturer: Images Scientific Instruments.

The chip has two operational modes; manual mode and CPU mode. The CPU mode is designed to allow the chip to work under a host computer. This is an attractive approach to speech recognition for computers because the speech recognition chip operates as a co-processor to the main CPU. The jobs of listening and recognition doesn't occupying any of the computer's CPU time. When the HM2007 recognizes a command it can signal an interrupt to the host CPU and then relay the command code. The HM2007 chip can be cascaded to provide a larger word recognition library.

The SR-07 circuit we are building operates in the manual mode. The manual mode allows one to build a stand alone speech recognition board that doesn't require a host computer and may be integrated into other devices to utilize speech control.

Applications

Command and control of appliances and equipment
Telephone assistance systems
Data entry
Speech controlled toys
Speech and voice recognition security systems
Three PCB boards are available for this project, see parts list. The components are mounted on the top side of the board, . Begin construction by soldering the IC sockets on to the PC boards. Next mount and solder all the resistors. Now mount and solder the 3.57 MHz crystal and red LED. The long lead of the LED is positive. Next solder capacitors and 7805 voltage regulator. Solder seven the seven position headers on the keypad to main circuit board . Next solder the 10 position headers on the display board and main circuit board.

1. Please reply from now on using the "Post Reply" button within the thread, rather than creating a new topic in the top-level Forum -- this will make it much easier for people to follow this thread. I'll ask a moderator to put all the previous stuff into one thread.

2. My internet connection is getting very cranky -- I may disappear from the net at any time. Other "experts" will cover if that happens.

3. The snippet you provided is interesting, but what I asked for was the vendor to go with the part number, plus full data sheets. A web link would be good. I may be able to download these once the vendor is known to me. Also, I need full details of both sides of the I/O link, the voice recognition device (some boards or perhaps you have your own breadboard using the HM2007 chip?) AND the RC device.

4. I'll probably need to find one of our team of volunteers who is an EE to get to the next step -- I am an astrophysicist with limited experience building devices at the chip level. This will take time...

you can find all the information about this circuit on the web.you can also see different images for it.sorry for all the trouble.i'm new to these kind of stuff.so,i don't have much experience.i'll try to get as much information as i can.

Hello Gijoe1442,

Even though you have written several times, I don't think we can answer your question yet.

Does your transmitter have a connector for external controls input? Does the documentation with the transmitter explain what kind of signals it expects to be connected?

I found an explanation of the SR-07 device at http://www.imagesco.com/speech/SR-07.pdf. If you have the same sort of description for your transmitter, the two documents studied together should explain how to connect up the SR-07 outputs to the transmitter inputs.

Good luck, WW

What did they mean by manual controls? Does my car have to have the same frequency as the car in the PDF you sent?

Gijoe1442,

A search of the pdf file I mentioned using Adobe Reader does not find the phrase "manual controls," so I don't understand your question.

The frequency of the transmitter and car receiver should not affect the connection between the voice recognition circuit and the transmitter.

WW

The RC car operator will have the option to operate the car
manually using the available remote control. This is done by connecting the appropriate speech
recognition interface connection and the connection from the manual controls together to a logic
OR gate which connects to the RF transmitter in figure 4.1.

Gijoe1442,

What document does the text in your last message come from? You seem to be reading a document that is not available to me. Please indicate whether the document can be accessed on the WWW.

WW

Well, I've had a quick scan of all the documents (at last!!). It seems that what you want to do is pretty much what the gatech students proposed: take some pre-existing, off the shelf modules and build a voice-activated RC car. All that needs to be designed is the interface from the TTL outputs of the PIC chip in the "SRI-04 X10 Speech Recognition Interface" (a PIC chip plus $5 worth of components) to the inputs, specified only as compatible with the RC car's own manual controls. Since I don't know anything about the RC car, it's impossible for me to say much about that interface. I feel that the discussion in the gatech students' proposal was naive to say the least -- just putting the symbol for a logic gate on a line representing a control path is meaningless. Looking at this proposal makes me worry that these students may be out of their depth performing even a trivial design.

Had they worked out the necessary details of the interface to the RC car control module, you could copy them. However, if this effort is supposed to be a science fair entry, I don't see where there would have been any intellectual work on your part. Luckily for you they failed to do this; thus conquering this problem could be the core of your science fair project. You will need to do four basic tasks:

1. Obtain full electrical and mechanical specs for the manual interface of the the RC car you are using.

2. Learn the basics of digital engineering necessary to connect the TTL outputs of the SRI-04 X10, or even better the TTL outputs on the header of the speech card you already have following the design given as part C of Figure 5 in the "SR-06/SR-07 Speech Recognition Kit Construction Manual & User Guide", to the input circuitry of the RC-car controller. I would recommend studying "The Art of Electronics" by Paul Horowitz (full disclosure -- he's a friend of mine). You might also find "The Art of Electronics Student Manual" to be useful. These are expensive to buy (but not so much compared to the kits, etc, you've already purchased) so either go used or find them in a library.

3. Design the interface. It's simple enough that you probably won't need software design tools.

4. Assemble the circuit on a breadboard and debug it. You will need a 30 MHz (100 MHz preferably) oscilloscope, a regulated 5V power supply, a bunch of test leads, and a few small tools that you probably have already from assembling the kits. A multimeter (DMM) might also be handy although not essential. The oscilloscope will be expensive -- $500 to $1500 -- see if you can borrow one.

Good luck with this challenging project!!

well,there are a few videos on youtube that show the connections i need but they're not clear enough.do you think you might find much better videos?if you can, i'd like you to explain to me what's going on.thanks a lot!
would an Ultrasonic Module HC-SR04 Distance Sensor For Arduino work instead?

Gijoe1442,

"This is done by connecting the appropriate speech
recognition interface connection and the connection from the manual controls together to a logic
OR gate which connects to the RF transmitter in figure 4.1."

The manual controls mentioned are controls other than the voice activated ones. They might be a steering wheel, joystick, switches, etc. You could just disconnect those controls and substitute the signals from your voice circuit or use an "or" gate to cause an action if either the voice or manual control produces a signal. Of course, your transmitter will have to have an external control input or you will need to tear into it to find the place to insert your signals.

The details of this connection depends on the details of your voice circuit and the transmitter. It is quite common to have to use some sort of converter to change the polarity or voltage of the signals to make the circuits cooperate. If this still doesn't make sense, I think you may need to learn a bit of digital logic.

WW