Switch to PIC to Transmitter Interface

[loftust]

Hi, i'm Matt from the British Royal Navy. I need to design and build a Transmitter unit controlled by a PIC with several switch Inputs.

A more detailed description of my proble is that i have to build a water propelled rocket. I'm designing the control side of things. I need to be able to remotely actuate a compressor to fill up the bottle and then stop the compressor. I also need to be able to abort the launch of the rocket and be able to remotely actuate the release mechanism. On top of all that, i need to be able to remotely control the azimuth and elevation of the launcher.

If you have any ideas/suggesions on the technical side of things, i would be most grateful.

Cheers.

 

[Rheinhardt]

If i understand right :

Inputs : Compressor pressure Digital/Analog??
Release mechanism Position feedback DI
Elevation feedback AI
Azimuth (AI ??) Expand what this is pls.

Outputs : Compressor Start DO
Release mechanism DO
Elevation Control AO
Azimuth control AO

If you could post a small drawing of the system that can help. What type of PIC are you using. Important will be the amount of ports avaible . You might need a couple of external devices for your analog control. The Analogs you can bring in on a singled port and in your source code scale it to a value which is usable.

Any additional information can help, but start with a system schematic, showing parts used ect.

Regards

Rheinhardt

 

[Rheinhardt]

Does this unit of yours gather the remote data and then transmits it via RF(Radio Frequencey signals??) PLs elaborate more on the transmitter part that you mentioned??

 

[loftust]

Thanks for responding,

I/P: Analog Compressor. Azimuth is like the bearing on a compass, its a direction, i have to be able to control the bearing of the rocket(Sorry my fault, Naval terminology). I'm using an alpha-numeric display to indicate the bearing and elevation via feedback from the launcher.
Im using a PIC 16f876, i know its not very good, but its extremely cheap and has the right amount of pins for what i need. I'm using an esay radio ER400TRS transceiver, because seperate Tx and Rx will require an expensive device to allow them to use just one aerial. The box is very small as well.

Will try and get a diagram ASAP

Cheers

 

[hrc]

what kind of range are you looking for?

http://www.maxstream.net

Xbee modules....small...serial uart interface. Just send data back and forth.

 

[loftust]

I'm only looking for around 150m, nothing spectacular.

 

[hrc]

Xbee would do the job, they run about $20 USD each, need two of them. Use the built in UART in the 876 to talk to it. Simple comm routine, using the interupts to watch for the traffic. Basically, just send codes back and forth for filling and sending back status.

As far as controlling the launcher...isnt this going to be a seperate circuit? Or is the bottle fill/stop control located on the launcher unit as well. To get elevation information just use a accelormeter to measure that.