GPS used to direct a rover to a known destination ???HELP???

[fakahany1]

Hello guys.
I have this idea and we need it to be developed by my fellows here )
Well, I am woundering what is the logic of such project: I have a rover for example with GPS capabilities. AND I WANT THE ROVER TO HOME TO A PRE-KNOWN DESTINATION (gps location). How would the rover by knowing its current location can determine how to go to the target ????? the rover knows it is in position (X1,Y1,Z1) and it knows that the target destination is at (X2,Y2,Z2), what is the mathematical logic that the rover can use to determine its path (points on its path that can lead to the target destination)....... is there any mathematical model or logic that i can draw to understand it????? and if so does any one have suggestions to the type of microcontroller that would enable me perfom such mathematical operation????
thank you alot guys hope to see your ideas and help have a nice day

 

[Oznog]

There is a standard protocol you can use to talk to a GPS module. I forget what it is, search the Web. Any microcontroller can interface with it. PIC seems to be the most common controller for hobbyist use. There are GPS modules on eBay which don't have a screen or maps, they just output coordinates.

GPS cannot determine which direction the machine is pointed in. As such, if you have no data on its direction, all you can do is drive forward and see what direction it moves the coordinates in. Lack of high resolution accuracy in GPS may require a fairly long drive to figure this out. Fortunately, while GPS has at best around 30 ft absolute accuracy, the relative accuracy to a measurement taken minutes ago can be quite accurate with a precision receiver. A magnetic compass may help determine direction much quicker.

Once you know the machine's orientation, you'd just steer towards in and hope there's nothing in the way. Many microcontrollers have plenty of room for whatever nagivation program you care to write.

 

[Klaus]

What you want to do is used in navigation every day.
The GPS gives you your present position.
By entering your destination as a waypoint the GPS will calculate and display the direction to it.
Once you are underway the GPS will constantly sense your speed and display the ETA (estimated time of arrival) to your destination. If the speed is constant the ETA is very accurate.

Keep in mind that the average GPS is accurate to about 10 metres. This is fine on my boat but may not be for your purposes.

If I wished so I could connect an autopilot to the GPS and it would steer automatically to the destination.

You would need something similar for your project. A GPS to get present position and the course to the destination. A magnetic compass driven autopilot to steer your craft. Some feedback from the GPS to stop the craft once it got to the destination.

All doable but expensive with commercial parts. Good luck with making your own :wink:
Klaus