When they first started to be commonly used commercially, hovercraft were seen as the future of transportation. Their ability to travel across both land and sea made them extremely versatile compared to trains or automobiles, and combined with low operating costs, it's no wonder they were so popular from 1960 to 1980.
Hovercraft operate by using a cushion of air that's contained within a skirt to float just above the surface. There is also a second fan positioned at the rear that provides thrust for forward motion, along with a rudder to provide yaw and steer.
Jacob Krizan wanted to take this concept and scale it down to create a personal hovercraft for traveling short distances. He began by cutting out two polygons from a sheet of insulating foam board and making holes in it for the air ducts and seat.
Next, he taped pieces of plywood onto the top to create an angular hull, as well as the mount for the rear fan.
After attaching the skirt along the perimeter, it was time to add the propulsion components.
As stated earlier, a hovercraft hovers by forcing air between the bottom of the hull and the ground, trapping it within the skirt. This project uses four, 1000W ducted fans that are used in radio controlled planes to generate the air cushion. Their compact size means plenty of lift is present within the small footprint of the craft. Two additional fans are used for lateral control. Each one is driven by a Turnigy 70A Red Brick electronic speed controller (ESC), which takes in the low-power signal from the RC receiver and converts it into pulses of power for the motor.
One last motor is situated at the rear to provide rear thrust for forward propulsion. It's a 6000W RC motor with a propeller driven by a 150A ESC and powered by 2x 8000mAh 40C batteries. At first, Krizan just controlled his personal hovercraft with a simple RC transmitter and accompanying receiver that sent the signals from the control sticks to the ESCs. However, he wanted to add some autonomy for more stability and system control.
To increase safety and ease-of-use, Krizan wanted to add an Arduino Nano and display to get a better readout of what the system is doing at any given time. At the moment, its architecture looked like this:
With the radio transmitter directly controlling the motors with PWM signals via the receiver and ESCs. In this new configuration, the Arduino Nano intercepts these signals from the receiver via an 8ch IBUS signal (to minimize interference), does some processing, and then outputs the PWM signals to the ESCs.
The Nano, 20x4 LCD screen, and RC transmitter were all fitted into a new dashboard and mounted at the front of the hovercraft. For now, the system can only output diagnostic information and track if the motors are enabled for extra safety, but Krizan does have plans to upgrade this in the future.
After booting up the hovercraft, a custom sprite can be seen floating its way across the screen.
It can also be observed that the values change on each corresponding axis for the rudder, thrust, lift, and left/right vector control.
All-in-all, the hovercraft works really well, and it will be exciting to see what upgrades come out in the future.