DADSS Technical Update

Over the course of the year, the DADSS Program has made some developments. In an effort to keep our supporters in the loop on all that we’re up to, we’ve put together a technical update on the latest in the development of the technology.

Senseair Breath-based system

Progress on the research continues to further increase the accuracy, precision and speed of measurement for the breath-based and touch-based devices as well as to reduce the physical size of the devices so that they may be eventually integrated into mass–produced motor vehicles.

A directed–breath sensor derived from the DADSS technology by Sweden-based sensor company Senseair is being tested by public transit workers in Stockholm to obtain real–world operational data and experience that is aiding the development of the DADSS passive breath sensor. In select locations, transit employees use the directed–breath technology to verify they do not have alcohol in their system before operating subway cars.

In the lab, testing continues to understand how a driver’s and passenger’s breath move through a vehicle’s cabin in order to identify optimal locations for installing the DADSS passive breath sensor(s). The engineers are using the BREATHS[1] simulator developed by the DADSS Program. The simulator blends gases including carbon dioxide, nitrogen and oxygen with moisture to create an “exhaled breath” that matches the composition, temperature and pressure of a natural human breath.

Touch-based system

On the touch-based system, engineers are working to reduce the number of lasers necessary to provide an accurate blood alcohol content (BAC) measurement in an effort to achieve the lightning-quick speed required for the technology and to decrease the physical size of the device so that they may be eventually integrated into mass–produced motor vehicles. To test the current prototype, the DADSS Program has created a touch-based standard calibration device that combines a series of compounds to accurately simulate the composition and density of tissue in a finger.

Human subject testing continues at the Harvard Medical School-affiliated McLean Hospital. This testing gives researchers the necessary scientific data they need for a wide range of driver ethnicity, gender, age, etc. The data is used to refine the measurement algorithms to be employed to determine a driver’s BAC while also validating and verifying the performance of the latest breath- and touch-based devices. These tests include a range of “real-world” scenarios – such as “last call” and “social snacking” protocols.

Pilot Field Operational Testing

The DADSS Program recently took delivery of the first 15 of 40 vehicles to be used in the first round of pilot field operational testing (PFOT) set to begin once federal government clearance has been obtained from the Office of Management and Budget. Work has begun to augment the pilot vehicles with the DADSS technologies and the needed instrumentation and data acquisition system. These tests will initially begin in Virginia and Massachusetts and will later expand to other select sites elsewhere in the U.S. The field testing will give researchers an opportunity to observe driver behaviors in real–world driving settings with a variety of natural factors such temperature, humidity and altitude. This will be an exciting step as researchers will gain valuable insights as the program moves out of the lab and onto the road.

[1] BREATHS means Biomimetic Respiratory Engineering Analysis and Testing with Humidity Simulator.