20% of road deaths are due to driving under the influence of drugs, and the number is rising. while reports of alcohol-related driving are decreasing, drug-related driving is increasing (brå Institute, 2021).

current drug testing methods are limited to a police officer's gut feeling based on irregular eye movements after a pen is moved in front of the face.

after that, it can take up to four hours to wait for a legally admissible urine and blood test to be carried out by trained personnel, while 25% of these tests turn out negative.

high mortality rates, low validity of tests, long waiting times, and high rates of error put police officers under enormous pressure while forcing suspects to undergo often considered intrusive testing.

our research uncovered potential technologies, including portable and accurate implementations of liquid chromatography-mass spectrometry that can measure drugs from the sweat of fingertips.

through rapid prototyping, we were able to demonstrate the impact of different technologies to the police and identify how they could support their work.

to help police officers and suspects through the testing process, the need to integrate digital and physical interaction emerged.

to avoid putting suspects under additional pressure by causing a stir, the device had to integrate seamlessly into the environment to increase discretion.

form exploration

we were able to get in-depth feedback on the final concept by creating a prototype that demonstrated the complete testing process with ui, buttons, leds and haptic feedback in the final form factor.

the test was non-invasive, couldn't be faked, was equally accurate, less expensive and took three minutes instead of two weeks in the lab.

substance:id guides the police officer and the suspect through the test procedure.

substance:id provides haptic feedback on success and/or attempted cheating to assist the officer in providing a confident test result.

the test result can then be displayed to the suspect, who is now confronted with a less vague result and more humane test conditions.