Navigating Before GPS: Maps, Symbols, and Signals
Before the advent of GPS units and built-in navigation systems, people relied on a variety of methods to find their way from one place to another. Despite the rapid technological advancements in recent decades, the history of navigation can be traced back more than 5000 years. Maps have long predated automobiles, and people navigated using paper maps, road signs, and even symbols on the ground.
Early Navigation Methods
Maps have been a crucial tool for navigation since long before the car was invented. The history of mapping can be traced back to ancient times, where maps were used to guide travelers and soldiers. Even as late as the Cold War era, the U.S. military found caches of maps made by ancient civilizations, such as one found on the island of Cyprus that detailed the road to Noah's Ark.
Walking, Riding, and Sailing
Before the invention of cars, people primarily navigated by walking, riding, or sailing. Travelers would walk or ride from town to town, and many roads still maintain the names of the next town they lead to. Early travelers would use various methods to navigate, including paper maps, nautical miles, and even kilometers. These maps served as essential tools for guiding them to their destinations.
Navigation by Train
Trains were managed by dispatchers who used route boards to track the location of every train on every track. Dispatchers had the critical responsibility of ensuring that no two trains were on a collision course. They would set switches to ensure each train got to its intended destination. Engineers relied on trackside signs and signals much like modern car drivers rely on road signs. The ultimate control lay with the dispatcher, and this system remains in place even with modern technology.
Air Travel Navigation
Air travel before modern technology was quite different. Pilots navigated by using charts and magnetic compasses. RNAV (Radio Navigation) was invented just before World War II, providing precision for landing approaches. Before RNAV, Ground Controlled Approaches (GCA) were used, where radar controllers provided voice commands to pilots to ensure they stayed on a proper glide path and centered on the runway. This method is still available in emergencies and has been depicted in numerous aviation films.
Modern Innovations
The world has seen significant advancements in navigation technology, with GPS units becoming standard in cars and smartphones. Even now, many drivers prefer to use Google Maps for route planning, manually adjusting routes as needed. However, GPS is only used for map-to-ground navigation in unfamiliar areas. The reliance on manual interventions suggests that the transition to fully autonomous navigation still has some challenges.
Examples of Pre-GPS Navigation Techniques
1. **Professor Bott's Braille Symbols (Botts Dots)**: In California, they adopted these tactile symbols, allowing for low vision driving without the use of a visual display. This method demonstrates how technology evolves to meet the needs of all users, regardless of visibility.
2. **Historical Air Navigation Methods**: Inspirational examples of historical navigation methods can be seen in aviation films, such as those depicting Ground Controlled Approaches (GCA), which used radar and voice commands to guide pilots during landings. This technology remains a backup in case of emergencies.
Conclusion
The evolution of navigation shows the resilience and adaptability of human ingenuity. From ancient maps to Botts Dots and from railroad dispatchers to modern GPS, each method has contributed to our ability to traverse the world with confidence and security. As technology continues to advance, understanding our past can provide valuable insights into the future of navigation.