Refine Transforms

[akevinge]

Currently, transforms are broadcasting GNSS-based odometry. For various reasons, including noise and instability, we should look to combine GNSS and IMU (/ouster/imu) to broadcast proper transforms.

Current code:

vehicle_interface/src/sensing/gnss/gnss/gnss_interface_node.py

Lines 89 to 105 in 3c9cc17

	def publishTf(self):
	if self.cached_odom is None:
	return
	# Publish our map->base_link tf
	t = TransformStamped()
	t.header = self.cached_odom.header
	t.child_frame_id = self.cached_odom.child_frame_id
	transl = Vector3()
	transl.x = self.cached_odom.pose.pose.position.x
	transl.y = self.cached_odom.pose.pose.position.y
	transl.z = self.cached_odom.pose.pose.position.z
	t.transform.translation = transl
	t.transform.rotation = self.cached_odom.pose.pose.orientation
	# self.get_logger().error(str(t))
	self.tf_broadcaster.sendTransform(t)

Ideas:

• GTSAM Example of GPS/IMU
• EFK or UFK on top of IMU data

[surajchips]

Status: Reading and understanding surrounding codebase.

Next Steps: Learn about imu data, how it relates to the lidar sensor, and what needs to be implemented. Also learn how to test code as a system.

Projected Completion: Depends a lot on how much we can rely on the existing codebase. If things don't work out: March 3rd.

Update: We have been trying to learn the vehicle_interface code. Unsure if a) imu data is already being published, b) imu data publishing needs to be added to an existing node, c) a new node needs to be created for a new device to publish imu data. Currently imu data seems like it would come from the lidar, but I'm unclear if the lidar nodes already publish that data or not.

[csakilan]

02/24/2025 Update:

• Status: cloned git repository and mapping out code.
• Next Steps: Learn more about IMU data and how it can be connected to GNSS to increase accuracy.
• Projected Completion: March 3rd.

[surajchips]

03/03/2025 Update:

Status: Trying to run simulation

Next Steps: Correctly run carla simulation, and test possible methods of integrating imu data.

Projected Completion: Mar. 17

Update: I have tried to download and run the carla simulation locally, but I have been unable to install everything do probably due to a system error, or the fact that I am running on a mac. I have done research on possible ways to integrate the imu and gnss data, and it should be simple once I figure out how to run the simulation and figure out the internals.

[smathashery]

03/03/2025 Update:

Status: Currently creating node in navigator to bring together imu and gnss data

Next Steps: Make a very simplistic combination of the imu and gnss data just to get the framework in place

Projected Completion: Apr. 7

Update: I'm currently making the node in navigator to try and combine the imu and gnss data. I've been able to access some of it. I am wondering how I should label the topics I'm subscribing to as the imu topic name will obviously be different when moving from carla_interface to vehicle_interface

[csakilan]

04/21/2025 Update:

• Status: Moved transform code into a separate node and pushed changes
• Next Steps: Making sure it works in the Carla simulator and adding IMU data
• Projected Completion: May 20