I am looking to develop a system to facilitate distance measurement between 2 Arduinos over a range of ~50ft to an accuracy of ~1ft. The 2 Arduinos will be mobile and the position and orientation relative to each other will vary, therefore techniques relying on line of sight and directionality are out.
I will be setting up an XBee network to allow for communications between the modules, and was hoping to calculate distances using these somehow?
I have considered using the XBee RSSI to calculate an approximate distance, however research has led me to believe that this will have very poor accuracy at best and more likely simply won't work. I have also considered a system based on radio time of flight (ping from Arduino A to Arduino B and back, time taken * speed of light = distance) however due to the speed of RF waves and the Arduino clock speed this is simply not feasible over such short distances.
Does anyone know of any alternative techniques that may be of use to me here? Any input would be greatly appreciated. Thank you
I am looking to develop a system to facilitate distance measurement between 2 Arduinos over a range of ~50ft to an accuracy of ~1ft. The 2 Arduinos will be mobile and the position and orientation relative to each other will vary, therefore techniques relying on line of sight and directionality are out.
Very frequent forum project issue. Haven't seen any solution that would normally be simple and affordable in a hobby context.
I was wondering. Since 4 years have gone by. Has a solution to this problem been found yet?
I also need the to measure distance between several objects that are continuously moving and can not use line of sight methods such as ultrasonic or infrared sensors.
the distance between the objects that I need to measure ranges from 10ft to 40ft.
ryan_sciortino:
I was wondering. Since 4 years have gone by. Has a solution to this problem been found yet?
No.
This question is asked several times a week (it seems) on these forums. Whilst a lot of people think they have an original cunning wheeze to use RSSI to measure distance, its just not consistent enough.
There are new devices starting to appear that can use RF time of flight to measure distance, but thats quite a different principle.
For those that might come across this thread some time in the future like I did, refer to the link below that will take you to a project found on Elektor magazine. In the project LoRa was used to measure very small distances.
What I can read of the article, most of which appears to be behind a paywall, claims to measure distances of miles. I have great difficulty with that claim, and it conflicts with your comment of "very small distances".
Please explain, and tell us why we should bother to read the article.
ryan_sciortino:
For those that might come across this thread some time in the future like I did, refer to the link below that will take you to a project found on Elektor magazine. In the project LoRa was used to measure very small distances.
That is using the Semtech SX1280 devices which have time of flight measurment capabilty, nothing to do with RSSI.
jremington:
What I can read of the article, most of which appears to be behind a paywall, claims to measure distances of miles. I have great difficulty with that claim, and it conflicts with your comment of "very small distances".
Small distances, say 50m seem to have an error of maybe +- 3m or so.
But at longer distances, 2km in the examples described below, more consistent;