Ride quality evaluation of an actively-controlled stretcher for an ambulance

Area of Science:

• Biomedical Engineering
• Transportation Safety
• Human Factors Engineering

Background:

• Ambulance transport involves significant acceleration and deceleration, negatively impacting patient ride quality.
• Conventional stretchers transmit foot-to-head acceleration, potentially increasing patient blood pressure.
• Actively-controlled stretchers (ACS) aim to mitigate these effects, but their ride quality requires further investigation.

Purpose of the Study:

• To subjectively evaluate and compare the ride quality of an actively-controlled stretcher (ACS) against conventional stretchers and an assistant driver's seat.
• To investigate the impact of different patient postures on ride quality during ambulance transportation.
• To determine the relationship between acceleration characteristics and perceived ride comfort.

Main Methods:

• Conducted ambulance transportation experiments simulating rapid acceleration and deceleration.
• Employed the semantic differential method and factor analysis for subjective ride quality assessment.
• Compared four transportation conditions: conventional stretcher (head forward/backward), ACS, and assistant driver's seat.

Main Results:

• The actively-controlled stretcher (ACS) provided the most comfortable ride quality among stretcher options.
• Reduced foot-to-head acceleration below 0.2 Hz and minimized acceleration variations correlated with improved comfort.
• Conventional transport with the head forward resulted in the poorest ride quality.

Conclusions:

• The actively-controlled stretcher (ACS) offers superior ride comfort for patients during ambulance transport.
• Minimizing low-frequency foot-to-head acceleration is crucial for enhancing patient comfort.
• Further research may be needed to address potential motion sickness associated with ACS movement.