Data Acquisition - Now and Towards the Future

September 22, 2021

Data Acquisition (DAQ) collects all the data from sensors on our cars and feeds it back to other departments and engineers in the team to make the cars as fast and efficient as possible. The team includes six sub-departments:

  • Cloud
  • Data
  • Design
  • Track
  • Users
  • Vehicle

DAQ displays all the data from the sensors upon the car and live-streams it to our telemetry server. From the server, the data is collated into values, graphs, live values and charts for other Redback departments to understand and use or for review at later dates. Simulation is also an important part of DAQ, including optimal lap simulators and driving simulators that allow the team to live-stream and test the car without running it.

Over the last few years, Redback Racing has been developing an end-to-end data acquisition, visualisation, simulation and web platform called Redback Cloud. The overarching goal of a motorsport telemetry system is to provide the tools for engineers to improve the performance of their cars. The key points we have been focusing on to achieve this are to:

  • Increase the number of data points collected on the car
  • Automate the cataloguing of data to increase the amount of time analysing it
  • Improve the accessibility and visibility of data so engineers can make greater use of it
  • Enable remote participation at track days to increase engagement in the team
Full data system architecture

The diagram above shows a high-level overview of the different parts of the system. The blue components are the projects which collect data from sensors and simulations, sending the data back to Redback Cloud - represented by the red components - either directly or via a proxy server at the track. The yellow components represent general-purpose computers with the Redback Cloud web portal to visualise live telemetry, perform lap simulations, search and analyse data etc.

Data Sources

The data sources are the entry point to the system, collecting data from sensors, inputs and simulators. The primary data sources are the onboard data logging firmware and weather station, which collect data at track days and send it to Redback Cloud.

As Redback could not take part in FSAE-A 2020, we had many spare hands to help develop supporting systems. We integrated these systems included the driving simulator and lap simulator, as data sources to Redback Cloud.

Moving forward, we can extend Redback Cloud to integrate many data sources or systems, including more simulators and sensors.

Firmware

At the start of 2017, Redback started a firmware project called Yuria to collect, process, display, stream and log the data from all the sensors and systems onboard the vehicles. Even as our oldest software project at Redback, we have accelerated development over 2020 and the start of 2021, as seen in the commit log.

The firmware aggregates data from many inputs onboard the car; primarily the CAN bus which is populated with data from analogue and digital sensors plugged into the ECU, as well as CAN-enabled sensors such as our IMU.

Graph of code commits from 2017 to 2021

Going forward, the electrics team is looking to decentralise the analogue to digital conversion away from the ECU by having CAN nodes throughout the car which will reduce the number of wires in the loom. Other inputs to the firmware are the GPS board which sends data over a serial port using the NMEA protocol - the standard for GPS - and the labjack which is a data acquisition unit with a series of analogue and digital inputs.

The firmware is structured using the concept of modules which each run in parallel in their thread. Modules are broken up into inputs, middleware and outputs, as shown in the diagram below. The threads pass messages to each other asynchronously through 2 data structures. The first being the Event Bus for general control messages like ‘start streaming’ or ‘start logging'. The second is queues for streaming sensor data through the pipeline from input modules to output modules. Through passing messages and decoupling modules from each other, the system is extendable to more use cases by inserting new modules.

Data logger firmware module based architecture

All modules and sensors connected to the system are configured in a JSON config file. For example, all sensors on the CAN bus are defined by their CAN ID, specific bit offset and length, endianness, data type and decimal point position. Thus, our firmware can be configured for any other car, not only Redback cars.

In 2021, we are further integrating the firmware with Redback Cloud by creating a user interface to configure all modules and sensors and automatically sync with the firmware on the car using the WebSocket connection. We are also working on being able to plugin more data processing to the middleware modules for use cases such as sensor fusion so that the firmware can operate as a ROS node in the autonomous vehicle system.

Weather Station

The weather station is a project deployed trackside and collects an array of data about the current weather conditions at the track, including:

  • Track temperature
  • Air temperature
  • Air humidity
  • Air pressure
  • Wind speed and direction

This data is streamed to the trackside proxy server and then to Redback Cloud, allowing all our engineers to take the weather conditions into account when drawing information from the data. All the weather station data is also logged with the sensor data from the car, permitting us to compare data across different track days.

Data Science

In 2021, we started a new project to involve data science students between data acquisition and vehicle dynamics. Machine learning models take data from the lap simulator, driving simulator and vehicle to predict potential setup and future design improvements. It is not clear yet how these technologies we are developing will tie into the whole system and whether they can be offered as a service to other teams on Redback Cloud someday.

The Future

Redback Cloud Accounts

Redback Cloud Accounts is a key feature where other teams can manage all their vehicles, users and roles within the system. Each garage will belong to either a team account or a personal account, and if you have a team account, you can manage the permissions for all the people in their team. This feature will turn Redback Cloud into a true enterprise software as a service (SaaS) platform for anyone to use.

Part Tracking

Another significant feature in the pipeline for Redback Cloud is part tracking, keeping a record of the amount of use for each part on the car. Like the car setup sheets, we can select which parts are used on the car for each log file and generate computer estimates and predictions for when parts will reach their end of life.

Open Source

Redback is working towards all of our frontier software open source (data logging firmware, Assetto Corsa telemetry app, point mass simulator, weather station etc.). By the end of 2021, our goal is to develop Redback Cloud to a stage where other FSAE teams or the general public can create an account and begin using our systems for their cars or sim racing using our open-source data tools.