Building a Smart Robot to Navigate and Recognize Objects

Table of Contents:

1. Introduction
2. The Main Mechanical Assembly 2.1 The Base 2.2 The Utility Stick
3. The Jetson Xavier NX
4. Adding the Springs and Control Panel
5. Power Systems 5.1 Powering the Xavier NX 5.2 Powering the O Drive
6. Wiring and Acknowledgements
7. Implementing TF and Odometry
8. Adding the Laser Scanner
9. Running ROS and Testing the Laser
10. Building a Map of the Environment
11. Implementing the Navigation Stack
12. Final Thoughts and Future Developments

Building the Really Useful Robot

The Really Useful Robot is a unique robot that boasts a substantial base and a versatile utility stick made of aluminum V-slot extrusion. Equipped with a Jetson Xavier NX and ROS capabilities, this robot has the potential to recognize household objects and perform practical tasks in a home or office environment.

The Main Mechanical Assembly

The main mechanical assembly of the Really Useful Robot consists of two essential components: the base and the utility stick. The base is designed to run around the floor without getting tripped over, providing stability and mobility. On top of the base, the utility stick, made of aluminum V-slot extrusion, is adjustable in Height and houses an arm that can reach the ground or surfaces at human height.

The Jetson Xavier NX

Running on a Jetson Xavier NX, the Really Useful Robot gains access to Nvidia's learning models, enabling recognition of household objects. Additionally, the robot utilizes ROS for mapping and navigation, incorporating a laser scanner for more accurate data collection.

Adding the Springs and Control Panel

To enhance stability, springs are strategically added to the suspension arm of the robot's mechanical assembly. This flap, featuring one of the casters, ensures that the robot remains balanced. Furthermore, the control panel, which includes an emergency stop, power switches, voltmeters, and buttons, is wired and integrated into the system.

Power Systems

The Really Useful Robot operates on two separate power sources. One battery powers the Xavier NX, while another battery provides the necessary power for the O Drive. A relay switch is incorporated to handle the high power requirements of the O Drive efficiently, ensuring seamless operation.

Wiring and Acknowledgements

The intricacies of the wiring system are discussed, highlighting the importance of key components such as the Arduino, Teensy, and laser scanner. The contributions of various companies, including 3D Fuel, Nvidia, Cool Components, and RoboSavvy, are acknowledged for their support in the development of the project.

Implementing TF and Odometry

TF (transform) plays a crucial role in determining the position and orientation of the robot in relation to its starting point. With the help of an Arduino and Teensy, TF messages, along with odometry data, are published, granting precise localization of the robot during navigation.

Adding the Laser Scanner

The addition of an RP Lidar A2 laser scanner brings another level of sensing capability to the Really Useful Robot. This laser scanner is strategically mounted in front of the utility stick to capture accurate data about the robot's surroundings. Transformations are also applied to ensure alignment between the laser data and the robot's coordinate system.

Running ROS and Testing the Laser

ROS nodes are launched on the Xavier NX to establish communication and data flow between different components. By running the raw serial and laser scan nodes, the laser scanner's functionalities are tested, ensuring accurate readings and mapping capabilities.

Building a Map of the Environment

Using the GMapping Package and laser scan data, the Really Useful Robot is capable of building an occupancy GRID map of its environment. The accuracy of the map relies heavily on proper odometry and laser data synchronization. The resulting map can be further tuned and edited Based on individual requirements.

Implementing the Navigation Stack

The navigation stack is the heart of the Really Useful Robot's autonomous capabilities. By integrating the KNOX robot project and Turtlebot config files, and fine-tuning the parameters, the robot can plan paths, avoid obstacles, and navigate through complex environments. The cost maps created ensure safe and efficient navigation.

Final Thoughts and Future Developments

The completion of the Really Useful Robot marks an important milestone in robotics development. With the foundation in place, future enhancements such as deep learning models, additional sensors, and advanced locomotion systems can be integrated to further improve the robot's capabilities and expand its range of tasks.

Highlights:

• The Really Useful Robot features a stable base and a versatile utility stick.
• Running on a Jetson Xavier NX, the robot can recognize household objects.
• ROS capabilities enable mapping, navigation, and laser scanning.
• The inclusion of springs and a control panel enhances stability and control.
• Separate power systems ensure efficient operation of the Xavier NX and O Drive.
• The TF and odometry implementation facilitates accurate localization.
• The laser scanner provides precise data for mapping and obstacle detection.
• ROS nodes and testing ensure proper communication and data transmission.
• The navigation stack enables autonomous path planning and obstacle avoidance.
• Future developments may include deep learning models and advanced locomotion systems.

FAQ:

Q: Can the Really Useful Robot navigate through narrow spaces? A: Yes, the robot is designed to navigate through narrow spaces and doorways, taking into account its physical dimensions and the inflation radius around obstacles.

Q: How accurate is the mapping capability of the Really Useful Robot? A: The mapping capability of the robot relies on the synchronization of odometry and laser data. With proper calibration and tuning, the resulting map can accurately represent the environment.

Q: Can the Really Useful Robot be controlled remotely? A: Yes, the robot can be controlled remotely using a workstation connected to the Xavier NX. This allows for convenient operation and monitoring of the robot's activities.