Every second counts when firefighters are rescuing people. The ladder trucks used for this purpose must therefore be equipped quickly and, above all, perform their tasks as reliably and safely as possible. That is why the Korean special vehicle manufacturer Hyundai Everdigm relies on robust and powerful automation technology from STW to control the turntable ladder and boom.
When a fire breaks out, things have to happen fast. Especially when people are in danger. Failure or malfunction of equipment or machinery can mean the difference between life and death. At the same time, firefighters need to be protected. This means that rescue vehicles used by firefighters must meet particularly high performance and functional safety requirements.
Hyundai Everdigm is one of the leading manufacturers of rescue vehicles in the Asian market. The South Korean company also manufactures construction machinery, mining equipment and cranes. The portfolio in the area of fire protection and rescue vehicles ranges from truck-mounted aerial platforms and turntable ladder vehicles to classic firefighting, equipment and tanker vehicles.
Rescue at dizzying heights
If a fire breaks out in a multi-story building and there are people on the upper floors, rescue teams usually use ladder trucks to rescue the endangered people from the emergency situation using the rescue cage. Turntable aerials are also indispensable for rescuing casualties at great heights, such as during construction work on roofs. Finally, the vehicles are used to assist in firefighting or to provide illumination. Ladder trucks are therefore a crucial tool for protecting and saving lives in emergency situations. The demands on the electronic components used to control the work functions are high, too.
Hyundai Everdigm relies on STW's rugged and powerful ESX.3cm mobile controllers. They monitor and control the working hydraulics of the stabilizers, turntable ladder and rescue cage of the Korean manufacturer's ladder trucks, taking into account a large number of sensor signals.
These commands are implemented by the vehicle's hydraulic system, which was designed and implemented by HAWE Korea. The subsidiary of HAWE Hydraulik SE and STW have been working together as partners for many years. Thanks to this close cooperation, machine manufacturers such as Hyundai Everdigm benefit from optimal compatibility between automation and drive components. In this project, for example, HAWE's software layer works on STW's controllers to ensure maximum precision when controlling HAWE valves.
Safe, automated support systems
The support of the vehicle plays a decisive role in the safety of the emergency crew and the people to be rescued. The width of the support directly influences the maximum operating range of the turntable ladder. This is because if the ladder is extended too far with insufficient support, or if the load is too heavy, the vehicle may lose its balance and tip over, creating a life-threatening situation for anyone in the vehicle's operating area.
The ESX.3cm controls the automated extension and leveling of the booms with the help of draw-wire encoders, tilt and pressure sensors. Using connected ultrasonic sensors, the system automatically detects whether objects are in the way and positions the supports in such a way that no damage is caused to surrounding buildings, people or infrastructure.
Positioning the boom
Another ESX.3cm on the superstructure manages the turntable ladder. It controls the positioning of the slewing crane on which the ladder is mounted, as well as the extension and retraction movements of the turntable ladder. In an emergency, the turntable ladder must be extended to the rescue site with millimeter precision. This requires a perfect interaction between the position of the turntable crane and the length and angle of the jib and the man basket at the end of the turntable ladder. This task is performed by the STW controller, taking into account the values measured by the inclination and position sensors, as well as the load-sensing system that prevents the boom from being overloaded. The automation system based on the ESX.3cm also prevents collisions with objects in the working area when the boom is moving.
Balancing the rescue cage
The control system of the rescue cage is based on an ESX.3cs controller. At this point, it is important to achieve the correct balance to ensure that the rescue team can work safely. The ESX.3cs controls the hydraulic system of the cage to ensure stability and therefore safety in the raised position, based on the load sensing system and a wind speed sensor. It is also crucial that the rescuer in the basket can take control of the boom to independently and quickly position the basket to ensure a safe rescue. This is where STW's compact mobile control system comes in. When controlling the work function from the rescue cage, the control system, in combination with the sensors used, also ensures that unintentional collisions are avoided.
Jonghyuk, Lee, Team Leader for Electrics and Electronics at Hyundai Everdigm, summarizes why the company chose STW's automation systems: "STW is a proven and specialized manufacturer of rugged mobile controllers that have been reliably used in many special vehicles on the market. The long-term availability of the components was also crucial for us in view of the volatile electronics and microchip market. STW convinced us with its intelligent obsolescence management. In addition, HAWE Korea, a partner of STW, provides local support. HAWE supports us with training, assists us with maintenance and is always available as a technical contact".