Research methods

Participants: 6 drivers (2 contract drivers, 4 engineers), ages 31–62, with 8–34 years of trucking experience

Format: 1–1.5 hour in-person surveys & interviews at PACCAR Technical Center in Mount Vernon, WA

Data Collected:

1. Quantitative: Likert-scale satisfaction, likelihood-to-use, and performance ratings

2. Qualitative: Open-ended questions on positive, negative, and surprising experiences

Interview Guide Structure:

1. Demographics + warm-up questions

2. Evaluation of individual features

3. Evaluation of overall system

4. Closing reflections

Analysis:

1. Qualitative: Thematic analysis in FigJam (digital sticky notes, iterative clustering)

2. Quantitative: Averages calculated for satisfaction, likelihood, and performance

overall RESULTS

According to the criteria of the 1-10 scale, Traffic Sign Recognition, High Beam Assist, and Lane Departure Warnings were the features that received passing performance ratings. Adaptive Cruise Control and Forward Distance Alerts did not. Not enough people experienced Highway Departure Braking and Automated Emergency Braking to be able to capture meaningful quantitative data around its performance. This is admittedly a limitation of the study, but one that cannot and should not be remedied; drivers are not encouraged to deliberately activate these features for obvious safety reasons, and most encounters tend to be false positives. For data around how these emergency features perform during a true positive scenario, a controlled validation test would be best, not a driver study. Finally, the overall system (Fusion 3.0) received passing performance ratings.

Participants had a lot to say about ACC in particular, and notably, it was cited as the thing that works best about the overall system and also the thing that needs the most improvement. Participants were impressed by its ability to maintain a set distance and adapt to the flow of traffic (what works best) but they also acknowledge that its braking functionality should be improved (what needs the most improvement). The specific braking behavior that needs to be improved are the lack of smoothness and audible pulsing noises coming from the foundation brakes. ACC is arguably one of the most significant, and complex, Fusion 3.0 features, so special attention to its performance should be paid in the future because it has the most potential for impacting the driver experience significantly.

One of the most significant themes that came up across features was audible noises. Drivers felt mildly annoyed at best, and distracted at worst, by the sheer frequency of sounds coming from the system. Some of these sounds were warnings and some of them were notifications of something faulting. The inconvenience from warnings came from the false positives that sometimes where prone to happen (ex. LDW in construction zones, ACC when vehicles are exiting the highway, FDA when overtaking another vehicle, and so on). Alone, false positives from a single feature are tolerable. But together, they can be a nuisance. It definitely can be argued that false positives are better than false negatives when it comes to an ADAS system, but one has to consider the effect of desensitization after a while, which indeed was mentioned by at least two drivers.

The inconvenience from fault notifications came almost exclusively from ACC. These manifest as a “bombardment” of notifications that the driver largely cannot do anything about, but is forced to hear, whether they are accurate or not. For example, sometimes drivers would get notifications about ACC faulting even if the system was still functional. But typically, the notifications happened during inclement weather when camera or radar function would be compromised. They would also happen during startup. And they typically happen multiple times during a key cycle. This is especially difficult for drivers when they cannot easily remedy the fault on a long-haul drive. In future versions of Fusion, special attention should be paid not only to preventing these faults in the first place but considering how often the audible notifications need to occur.

Overall, the system’s weaknesses (such as fault notifications, frequent audible noises) ultimately do not detract from its performance. Improving on them will make the driving experience more pleasant, but the Fusion 3.0 system is already a helpful enhancement to the overall driving experience, according to drivers.