Understanding RTK: A Closer Look at Kiwibot's Autonomous Positioning System

Imagine you're trying to find your way around a new city. You've got a map, but it's not super accurate. You might end up a few blocks off course. Now, imagine having a friend who knows the city like the back of their hand. They can guide you right to your destination, no problem.

That's kind of how RTK works. It's like having a super-smart friend who knows exactly where you are, even if your GPS is a little wonky. RTK uses two GPS receivers—one that stays still and one that moves around—to figure out the exact location of the moving one. It's like having a built-in GPS cheat code!

📡 What is RTK?

Real-time kinematic (RTK) is a technology that significantly improves the accuracy of GPS positioning. By using two GPS receivers—a base station and a rover—RTK can correct for atmospheric disturbances and other factors that affect GPS signals. This results in centimeter-level precision, making it ideal for applications like autonomous navigation, inspection, and construction.

🤓 How Does our RTK Work?

1. Base Station: A stationary GPS receiver with known coordinates is placed at a fixed location. To implement this in our operations, we're actively collaborating with the campuses to set up antennas on select buildings and working with public antennas nationwide to deliver this exceptional service. 
2. Rover: A mobile GPS receiver that receives corrections from the base station. This Rover antenna is installed in our fleet.
3. Correction Data: The base station transmits correction data to the rover, which uses it to adjust its position calculations.
4. Enhanced Accuracy: With RTK, the rover can achieve centimeter-level accuracy, far surpassing the capabilities of standalone GPS receivers.

We've been using RTK to help our Kiwibots navigate in open spaces. It's like giving our robots a superpower that helps our bots' algorithm avoid dangerous zones or zones marked with new obstacles that the robot can’t traverse or isn't allowed to travel in. find the fastest routes, and deliver packages right on time. It's been a game-changer for us! 

That’s why we want to share with you some of our learnings, take note 📝

👀 RTK FAQ

Q: What are the installation requirements for an RTK base station?

A: The base station needs a clear sky view to receive GPS signals. It should be placed on a tall building or other elevated location, away from obstructions like trees or buildings. The base station requires a power source and an internet connection.

Q: What are the potential benefits of installing an RTK base station?

A: Installing an RTK base station can provide several operational benefits, including:

• Improved autonomous navigation: RTK can strengthen the precision and reliability of autonomous vehicles and robots operating in your facilities.
• Research and development: RTK can be used for research projects and experiments requiring high-precision positioning.
• Inspecting and mapping: RTK can be used for accurate localization and mapping tasks, such as measuring building dimensions or monitoring environmental changes.

Q: Are there any potential drawbacks or risks associated with using RTK?

A: RTK's primary drawback is the need for a base station with a clear sky view. This may be challenging in some areas due to obstructions or building heights. Additionally, costs may be associated with purchasing and installing the RTK equipment.

Q: How does Kiwibot use RTK technology?

A: Kiwibot leverages RTK to ensure precise navigation and avoid obstacles while delivering packages to warehouses, closed environments, and university campuses.

Q: Will this antenna cause side effects to people's health or will it interfere with other communication systems?

A: The RTK antenna on the buildings is designed to receive radio frequency signals only and does not emit any. Meanwhile, the cellular router does emit radio signals, but it operates within the existing 4G-LTE infrastructure and is FCC-approved with FCC ID U8G-P1941. The base station has enhanced hardware commonly found on a commercial cellphone. 

🤖 Kiwibot's RTK Implementation Journey

Kiwibot's journey to implement RTK has been marked by significant progress and challenges. The company has successfully deployed RTK base stations across multiple university campuses, enabling its robots to navigate with greater precision and reliability.

Key Achievements:

• Improved Navigation Accuracy: Using RTK has greatly enhanced Kiwibot's robots' ability to navigate autonomously and operate safely and efficiently in complex scenarios.
• Reduced Operational Challenges: Incorporating RTK has decreased operational issues associated with GPS positioning errors.
• Enhanced User Satisfaction: RTK's heightened accuracy has improved Kiwibot's customers' user experience.

Main Pain Points:

• Antenna Availability: Ensuring the consistent availability of RTK antennas across different infrastructures has been a challenge. Factors such as weather conditions, physical obstructions, and network connectivity can impact antenna availability.
• Antenna Status Monitoring: Monitoring the status of RTK antennas to identify and address issues promptly has been another pain point. Kiwibot has implemented a system to track antenna availability and detect potential problems.

Addressing Challenges:

To address these challenges, Kiwibot has taken the following steps:

• Improved Maintenance: Implementing regular maintenance procedures to ensure the optimal performance of RTK antennas.
• Remote Monitoring: Utilizing remote monitoring tools proactively detect and diagnose antenna issues.
• Field Support: Having a dedicated field support team to address any on-site issues related to RTK antennas.

So, Next time you see one of our robots zipping around, remember that it can do its job so well thanks to this cool tech called RTK. It's like having a secret weapon that helps us deliver the future of transportation, one package at a time.

Written by:

Alejandro Serna , AI&Robotics PM

Natalia Hernandez , Comms Office