Are AGVs Safer than Forklifts
Do fork lifts represent a danger in factories? In the past years, the amount of severe machine accidents luckily decreased significantly. Unfortunately, this is not true for forklift accidents. Looking at the most recent statistic of the German Statutory accident insurance “Deutsche Gesetzliche Unfallversicherung”, DGUV), in 2016 alone 12.674 work related accidents with and by human-driven forklifts were reported. The alarming fact is that many of them ended with major injuries and several cases even deadly for the workers involved. The causes are often a limited visibility because of the load, carelessness or surprise moments. In these cases, automatic fork lifts are a safe and valid alternative.
Most severe accidents happen with human-driven forklifts
2016 the German Statutory accident insurance DGUV reported totally 33.868 accidents with floor-level conveyors in German factories. These include also wheel and sack barrows, handcarts as well as roll containers and hand pallet trucks. Also forklifts and Driverless Transport Systems (DTS) belonged to this sector. The alarming fact is that concerning the manned forklifts, not only a higher number of accidents were reported compared to the DTS, but also that in some cases people lost their life. By contrast, the number of accidents with DTS which ended deadly is zero.
In a great number of cases, the drivers were injured for example after crushing into other vehicles or structural facilities or because the forklift tilted. Another study reports that 44 of the affected people were non involved persons, who got hit, crushed or even overrun. This happens almost equally while driving forward, reverse or rotating.
Several incident causes
Forklift drivers have a limited visibility and work often under pressure because of tight deadlines. Non involved people are sometimes not aware of this visibility limitation and step into or cross the forklift traffic area suddenly and careless.
Often forklifts drive at a high speed through the manufacturing facility. If the drivers are not properly buckled on, they risk their life like in a car. “The forklift tilts, for example because the driver enters a curve too fast, because he accelerates too much while driving reverse or because he drives against a lane border”, explains Marcus Gaub, expert for floor-level conveyors in the Department of Trading and Logistics (Fachbereich Handel und Logistik, FBHL). The German Trade Association for Vehicles (Berufsgenossenschaft für Fahrzeughaltungen, BGF), listed the most common incident causes with forklifts (BGF, Source: DGUV Information 208-004) :
- Hitting people
- Overthrowing of the forklift
- Error while picking the load
- Driving and operating errors,
- Errors by loading and unloading of the vehicles
- Maintenance and repair works
- Unauthorized passengers as well as unauthorized use
Do Driverless Transport Systems solve the problem?
Looking at the accident statistics, the answer must be “Yes”. Automatic driven forklifts move through the halls with a fixed, set maximal speed, which normally doesn’t exceed 1,6 m/s (which is about the human walking speed). Automatic driven vehicles are furthermore equipped with safety laser scanners, which recognize people and obstacles very far ahead. The vehicles react immediately and reduce their speed, as soon as someone crosses their path. They move along defined routes, so that they don’t change direction unexpected. Because they drive slower and proactively, the employees feel from experience safer then with human-driven forklifts.
However, their low speed does not mean that transport robots lose against human-driven pallet trucks concerning the performance. The vehicles work continuously and don’t need any break, also the charging times are very short thanks to a modern battery technology. Driverless vehicle fleets are furthermore scalable. That means, that an additional vehicles can always be added to the fleet, if the existing ones are not enough. The investment in a driverless pallet vehicle is moderate and profitable after a short period of time.
Personal safety is of course the main issue while using DTS. Possible dangers should be considered while planning the system as a part of a holistic material flow concept.
Automatic driven pallet vehicles by InSystems Automation
InSystems Automation implements the transport robots individually in the manufacturing environment at the customer’s site and creates a specification in order to eliminate possible risks from the beginning.
In collaboration with Stöcklin Logistik AG and BlueBotics SA, InSystems Automation offers proANT 576 for pallets until max. 1.200.kg load. The driverless pallet truck loads pallets fully automatically and navigates around a once learned contour fully automatically along virtual lines to its destination. The vehicles has several safety systems: two safety laser scanners on the back and two on the front monitor constantly the driving area. Two lightning buttons on the fork ensure a safe loading and unloading. For example, pallets can be dropped only if the dropping area is free. Further laser scanners on both sides of the vehicle scan the driveway for possible obstacles.
proANT adapts its speed to the environment and always stops safely, For this purpose, warning and protective fields are set in the safety laser scanner. They reduce the speed of the vehicle or stop it, if a danger is detected.
Picture in the posting:
© Stöcklin Logistik AG