Application StoriesPLCProductProgrammable Control

Contemporary Controls Combined with Classic Camper Chic

This retro-look travel trailer is custom-built using aircraft fabrication principles, and the all-electric support systems are automated and visualized using a PLC and other components from AutomationDirect.

As a self-employed consultant with many years designing, building, and automation state-of-the-art manufacturing equipment, Scott Sutton is a hands-on guy. So, when his family came up with the dream of creating their own travel trailer camper with classic post-World War II styling—but all the modern amenities—he knew the task was right up his alley.

Scott’s article in Machine Design November 2021 titled Factory Automation is on a Roll describes how he and his wife made the dream a reality, even when forced to overcome several setbacks.

Rough Road

About ten years ago, Scott and his wife laid out some ideas and started planning. However, over the next seven years his wife suffered a heart attack, Scott received a cancer diagnosis with a poor prognosis, and he sustained a knee injury requiring major surgery. However, they kept up hope for their camper project, and Scott was inspired to contact Zenith Aircraft company to see if they would partner on the project.

Old and New

Zenith sells aircraft kits, and the camper was intended to use the same riveted aluminum fabrication style, so this seemed like a good fit. The owner of Zenith indicated that they might consider offering a travel trailer kit at some point in the future. The trailer would have retro style both outside and inside, but would feature fully modern and all-electric support systems for:

  • Inverter-driven mini-split heat pump (acts as a heater and air conditioner)
  • Induction cooktop
  • Electric water heater
  • Electric refrigerator
  • Microwave
  • LED lighting

Even after sourcing the highest-efficiency version of all the equipment, Scott knew he would need to implement a “load shedding” scheme to manage which loads should run and stop based on the available electrical service at a typical campground.

Contemporary Controls

Based on Scott’s automation experience, especially with AutomationDirect PLCs and associated products, he knew just what was needed.

An AutomationDirect BRX PLC would monitor the current of each load, and compare the available and requested power thresholds, so that the least critical loads would be interrupted as needed to stay within the available power supply. Solid state relays switched the heaviest loads, while high-speed pulse-width modulation outputs were used to vary LED lighting brightness and heat pump condenser fan speeds. The latter was important to optimize efficiency while reducing noise.

AutomationDirect offers many types of capable industrial HMI displays, and even an industrial-grade ProductivityOpen Arduino-based controller. However, for this application a consumer-grade Raspberry Pi running Python code was used. It communicates with the PLC using Modbus TCP as the HMI, and is also used to perform other PC-like functions, such as web browsing and multimedia display.

Down the Road

Since the camper was  completed, Scott and his wife had made dozens of trips, including displaying the camper with Zenith Aircraft at AirVenture, the largest airshow in the United States. The camper has been tested in all sorts of conditions, and the BRX PLC and associated controls have performed flawlessly. Data logging was useful during testing but is not needed in operation.

In the future as more features are added like solar power, mobile control capabilities, and a security system, the data logging utility of the PLC will be used once again to optimize all the systems. In some ways, the travel trailer is an advanced ‘rolling factory’, and we followed the same design, development, and testing steps necessary for any type of automation project.

Scott and his wife are thankful for the friends and organizations who helped them turn this dream into a reality.

All figures courtesy of Scott Sutton