RF-Triggered Motorized Stretcher Dispatch with in-Transit Vital-Sign Telemetry for Shortening Ambulance-to-ICU Hand-Off

Arunkumar S. — 2026-10-12

A road medical emergency is governed by two separate delays: how long the ambulance takes to reach the hospital, and how long the patient then spends being handed over from the ambulance to the intensive care unit (ICU). This paper targets the second of these by building and bench-testing a low-cost Internet of Things (IoT) system that pairs an ambulance-side patient-monitoring kit with an automated, radio-triggered stretcher. An Arduino UNO-based acquisition unit reads a patient's heart rate, blood-oxygen saturation (SpO2), and body temperature throughout transit and pushes the readings to a ThingSpeak cloud dashboard over an ESP8266/ESP01 Wi-Fi link, letting ward staff see the incoming patient's condition before the vehicle arrives. Separately, a 433 MHz radio-frequency (RF) link between the ambulance kit and a NodeMCU-controlled motorized stretcher detects ambulance proximity and releases the stretcher toward the drop-off point, removing the need for staff to fetch it manually. A working prototype of both units was built; ten consecutive vital-sign samples logged at 10-second intervals confirm sensor consistency, and the RF-triggered drive actuated reliably across bench trials. The design is then discussed against 2023–2026 developments in acoustic and AI-based ambulance detection, connected-vehicle signal preemption, and autonomous in-hospital patient-transport robots, closing with a roadmap toward obstacle-aware navigation and city-scale green-corridor integration.

A Microcontroller-Free Analog Line-Following Node as a Low-Cost Edge Sensor: Design and a Proposed Sensor–Cloud Integration Architecture

Jalp Patel — 2026-11-02

Sensor-cloud systems typically assume that every sensor node has a microcontroller, some firmware, and a network stack. For a whole host of simple tasks (e.g., following a line on a factory floor), this is more than is required. This study looks at a path-guided robot that has been built with absolutely no microcontroller in it and asks the question of how such a simple analog sensing node can still be part of a cloud-connected system. The robot has two pairs of IR reflective sensors, two LM358 op-amps used as comparators, and an L298N motor driver, all powered from a 9V battery via a 7805 regulator. Each of the comparators converts the level of reflected light into a single logic signal, which then drives one of the motor channels directly. The study describes how the comparator threshold is set and what it is limited by, and then proposes a layered architecture in which a low-cost gateway can read the same logic signals without in any way disturbing them and then send event messages to a cloud broker for storage and a dashboard. A worked example under the stated assumptions indicates that the event reporting will require around 10 times less data than would be the case if raw samples were uploaded. A test plan is provided for measuring threshold behaviour, response to ambient light and path following success. The main drawbacks of the analog approach are its poor performance in the face of sharp turns, junctions and high ambient light. The work demonstrates that a hardware-only sensing node can be the very first and cheapest layer of a sensor-cloud system and makes it very clear what is built and what is merely proposed.

Journal of Control and Instrumentation Engineering

RF-Triggered Motorized Stretcher Dispatch with in-Transit Vital-Sign Telemetry for Shortening Ambulance-to-ICU Hand-Off

A Microcontroller-Free Analog Line-Following Node as a Low-Cost Edge Sensor: Design and a Proposed Sensor–Cloud Integration Architecture