This project is to build a RC hovercraft which can go over flat land to attend Summer 2014 Introduction to Engineering competition. This competition is held by UMJI-SJTU Joint Institute (JI) in Shanghai Jiaotong University. Shanghai Jiaotong University is one of the Top3 universities in China and is famous for its strength in mechanical engineering and electrical engineering.
The competition includes two separate parts: time trial and tournament. In the time trial, all 19 team are required to finish one lap within the time limit (3 min) on the racing track. The arrangement of the tournament is based on the performance of each team in the time trial. In the tournament, two teams will start at the same time and complete two laps on the track; the faster team will be the winner. During the game, crashing and shortcuts are strictly banned.
At last our team Brave Heart got the second places among 19 teams in both the time trial (13.44s) and the tournament.
The central processor of this hovercraft is an Arduino Mega board; and a PS2 handle is used for remote control. Two ducted fans with brushed motors fixed at the back are used for propulsion. Adjusting the speed difference between them can make the hovercraft turn. The upper Acrylic board, the foamed plastic frame, and the bottom Acrylic board with holes, together form an air chamber in which air can gather together. A ducted fan with a brushless motor at the center can blow air into the air chamber; and thus decrease the friction between the hovercraft and the ground.
The following table lists all materials that you need to build a RC hovercraft. Some other common tools
including craft knife, insulating tape and hot glue gun are also needed.
Material List and Budget:
Arduino Mega Board: 69 RMB ($11.10 USD)
PS2 Handle with a Receiver: 45 RMB ($7.24 USD)
Li-Battery (11.1V, 2200mAh): 115RMB ($18.51 USD)
Brushless Motor with Ducted Fan: 99RMB ($15.94 USD)
Brushed Motor with Ducted Fan ×2: 30 RMB ($4.83 USD) ×2
Large Power Motor Driving Board: 139 RMB ($22.38 USD)
Brushless Motor Speed Controller: 56 RMB ($9.02 USD)
Acrylic Board (1.5mm, 30cm×40cm) ×2: 8 RMB ($1.29 USD) ×2
Plastic Foam ( 80cm×80cm×3cm): 15 RMB ($2.41 USD)
Total: 614 RMB ($98.85 USD)
We hope you enjoy reading this instructable and think it useful to you. Of course our hovercraft is not perfect; therefore we would really appreciate it if you can give us some feedback.
Step 1: Cut the Foamed Plastic Frame
The overall shape is shown in the figure.
Upper surface: 23cm*18cm; lower surface:
27cm*21cm; hollow: 21.5cm*16.5cm.
After cutting, remember to use sand paper to sand the rough edges.
Step 2: Laser Cut
Draw two CAD blueprints according to the figures attached. Laser cut two 1.5mm acrylic boards. The first one is used as the base plate; and the second one is used as the upper surface. Then glue the base plate to the foamed plastic frame. The upper surface should be glued later after the ducted fan is fixed on it.
Here we cannot give the exact parameters of the CAD blueprints because they are directly determined by the ducted fan you buy. The radius of the hole on the top acrylic board should be a bit larger than that of the ducted fan so that you can fix it easily using hot glue gun. In addition, there should be a small hole beside the big hole on the top acrylic board so that the wires of the brushless motor can pass through it and connect to the controller and battery on the upper surface.
Step 3: Construct the Frame
Fix the ducted fan with brushless motor on the top acrylic board according to the figure. Pass the wires through the small hole. Glue the acrylic board to the foamed plastic frame.
Seal all edges with tapes to make sure that the air cannot come out from the side of the air chamber.
Step 4: Fix the Electrical Components
Tape all electrical components (Arduino board, motor driving board, brushless motor controller, battery) onto the upper surface.
Remember to measure the weight of the electrical components that you buy. The positions of the components may not be completely the same as ours; because you will have to make some adjustments concerning the mass distribution to balance the hovercraft.The attached figure shows our arrangement; and you can refer to it. Balance is extremely important if you want your hovercraft to go straight enough and to make sharp turns easily.
Step 5: Fix Propulsion Fans
Referring to the figure, dig holes on the foamed plastic to fix the propulsion fans (Remember to glue it). Then glue the foamed plastic blocks onto the upper surface using a hot glue gun.
Step 6: Connect Wires
Connect wires according to the circuit diagram
Step 7: Write Programs
Write programs to control the hovercraft. It is an enjoyable process to adjust the speed parameters in your programs. Find the parameters that suit your own hovercrafts best!
Step 8: Enjoy!
Practice controlling the hovercraft and compete with your friends. Enjoy yourselves!