U-Blox positioning technology produces striped lawns

  • June 23, 2021
  • Steve Rogerson

Centimetre-level GPS technology from Swiss firm U-Blox can simplify precise positioning for robotic lawnmowers and e-scooters.

The company has released a firmware update for its Zed-F9R positioning module, bringing centimetre-level positioning to slow moving use cases such as robotic lawnmowers, e-scooters and shared bicycles.

Based on the Zed-F9R high-precision sensor-fusion module, the Zed-F9R-02B was designed for use in autonomous and industrial applications that require simple and efficient implementation and where rapid access to accurate positioning data is key, even in difficult signal environments such as dense cities.

The Zed-F9R uses the firm’s F9 multi-band global navigation satellite system (GNSS) receiver platform to track up to four GNSS constellations concurrently.

Applying real-time kinematic techniques, the module can derive positioning data with centimetre-level accuracy. The GNSS measurements are fused with data from the module’s inertial measurement unit, GNSS correction data, odometry information, and a vehicle dynamics model to provide positioning accuracy in situations where GNSS alone would fail. The receiver includes dynamic models for robotic lawnmowers, e-scooters and automobiles.

The Zed-F9R-02B integrates the U-Blox GNSS correction data service, broadcast in the scalable state-space representation format, making it easier to deliver fast time-to-market precise positioning products.

Robotic lawnmowers achieve further improvements in terms of their positioning accuracy thanks to the module’s ability to calibrate its dead reckoning system even at low speeds. The module’s accurate position output lets users precisely delimit the mowing area using software rather than with boundary wires and deploy robotic lawnmowers on complex lawn shapes while excluding trees and shrubs. Aligning each pass of the mower with the next more accurately than previously possible can deliver a professional-looking striped lawn.

Combining these features allows product designers to use the module to create mowing equipment that enables robotic mowing as a service capable of operating in complex environments without the upfront cost and commitment of installing boundary wires.

“Our new Zed-F9R-02B high precision module is a turnkey dead reckoning solution that will enable designers to bring products that need dead reckoning technology to market more quickly than if they had to implement it from scratch,” said Alex Ngi, product manager at U-Blox. “It will also allow companies working in niche markets to employ dead reckoning technologies without needing to build and maintain expertise in the subject.”

The Zed-F9R-02B offers support for a range of correction services, including the SPARTN format, which will make it straightforward to distribute GNSS correction data over large geographical areas.

With headquarters in Thalwil, Switzerland, U-Blox has offices in Europe, Asia and the USA.