Kickstarter Launched for NMEA Dongle to Connect GPS, iOS

January 15, 2015 - By GPS World Staff

Photo: NMEA

A kickstarter campaign has launched for an NMEA dongle that connects any existing GPS receiver to iOS devices. The device connects and communicates with high-accuracy GPS/GNSS devices and other field sensors that emit NMEA data to iOS devices over Bluetooth, allowing users to collect data on an iPad or iPhone using one or more sensors in the field.

Primary functions include:

overriding the internal GPS on iOS device with the location data coming from the external GPS so all existing apps using internal location services can benefit from the increased accuracy without any changes to the app.
providing the ability to connect with other field sensors that emit NMEA-format data (such as underground cable locators, lasers, resistographs, and audiographs) simultaneously with a GPS so data from multiple sensors can be incorporated into the data-collection application.

Garg explained the need for the dongle on his Kickstarter page: “The accuracy and precision of the internal GPS on iPads and iPhones is highly unreliable — it works fine for navigational purposes but fails miserably for mapping and asset management applications. The accuracy varies in range from a few meters to a few hundred meters depending on operating conditions, and there is no easy way to reliably ascertain that. Tests have proven that the accuracy rating on the location data returned by Apple is more of a general estimate than a reliable metric.”

The NMEA dongle is business-card-sized, and has an internal battery and a long-range Bluetooth. The dongle plusg into an existing GPS receiver’s serial port or connects via bluetooth to transmit the GPS data to the iPad. This allows users to feed RTK/NTRIP data to their iOS device.

“We have tested our solution with most of the leading brands of GPS receivers available in U.S., including Trimble, Topcon, John Deere, Altus, Geneq, EOS, CHC,” developer Sharad Garg told GPS World, “on most of the popular networks that we could get access to, including the Leica, Trimble, MyWayRTK, a few state-run networks and of course Unavco. Our solution is compatible with all of them, so its a very generic product at this point compatible with just about all the different solutions out there.”

Garg said his team also designed the dongle so that it allows users to connect to sensors such as laser range finders, valve exercising machine, Resistographs or agricultural sensors that emit data in NMEA format. The National Marine Electronics Association (NMEA) specification defines the interface between various pieces of marine electronic equipment, a standard that permits marine electronics to send information to computers and to other marine equipment.

“We have actually improved the design very significantly to be very modular and be compatible with all sorts of GPS connections that might be offered by the different vendors out there,” Garg said.

This YouTube video shows the dongle’s RTK functionality.