Introduction: K/\STEROID Game for Mini/Micro/Nano Drones
***Warning: the video above contains flashing lights.***
***Warning: this is a slightly complicated project that requires a bit of electrical engineering skills.***
This Instructable has been submitted to the "Sci-Fi" contest. If you like it, I'd really appreciate your votes.
I wanted to create a proper game for mini/nano/micro drones, that was exciting and cool even as a static model.
Being passionate about drones and having a son passionate about outer space "stuff", led me to find an inspiration from ARM (NASA Asteroid Redirect Mission, scheduled in 2020).
So, as a first step, my goal was to simulate the absence of gravity (keeping the asteroid floating in the air), therefore after having watched hundreds of videos on Youtube, I've decided to hack a hair dryer, removing the internal resistor (that heats the air) and the mica insulation.
Now, as I mentioned above there are a lot of videos on Youtube which explain how to do that (safely).
If you don't have a good knowledge of electronic engineering and safety, please don't attempt to hack the hair dryer.
Things like: verifying the hair dryer is disconnected from the socket before attempting to open it,
or, once you have removed the internal resistor, you must power the hair dryer with low voltage (preferably DC 12V),
or even that you must power the hair dryer when you are sure that the protections for the fan are in the proper place, should be taken very seriously.
Therefore, again: please use all the precautions!
If you think you don't have the right skills, don't attempt to hack the hair dryer.
After all, all you want to have is fun, possibly without being electrocuted, or having your fingers chopped off.
Step 1: Hacking the Hair Dryer (using All the Safety Precautions)
After having removed the resistor and the mica insulation, I've sawed the handle of the hair dryer with a hacksaw.
Then, I've sanded the shell of the hair dryer, painting it in grey.
I chose a Tesco hair dryer, because it's cheap and very well designed (regarding safety).
The protections for the fan are very good (because they leave a lot of space behind the DC motor, offering a better ventilation for the fan.
Last but not least, the back of the hair dryer is nearly flat (you need to sand the posterior protection - just a little bit -).
This is the equivalent product that Argos has currently on sale... http://www.argos.co.uk/static/Product/partNumber/...
Step 2: Installing the Landing Pads
When you finish to hack the hair dryer, you should have 2 wires connected to the DC motor (+ and -) coming out of the plastic shell.
You should now make 2 holes at the bottom of it.
After, you will stick the barbecue skewers inside the bottom of the hair dryer, being 100% sure they do not interfere with the fan...
and check again!
The hair dryer used for this Instructable has a lot of space behind the fan.
Now, glue the skewers to the shell of the hair dryer (eventually using UHU Por).
To createthe landing pad I used the box of the pastry cutter tool.
I used the top and I cut the base with the hacksaw, basically creating another top.
To have a better support of the landing pads, without having too much rolling on the barbecue skewer,
I glued under the pads the top of a plastic bottle (orange juice).
Step 3: Installing the Cylinder That Retains the Asteroid
To complete this operation, I bought a shrinkable water bottle, I cut the top of it, obtaining the same size of the diameter of the upper part of the hair dryer. Of course, I cut even the bottom of the water bottle.
I painted it in silver and I've placed it on top of the hair dryer.
At this stage I realized the airflow would have been affected by the wiggly shape of the water bottle, therefore, using the toilet paper rolls, I made a "sort" of cone which directs the air in a better way.
Step 4: Placing the Hair Dryer on the Turntable Display and Testing
I bought a turntable display.
Its motor is geared and it has enough power to spin slowly the "hacked" hair dryer.
Though I've already found a way to hack even the turntable display, installing a better motor and a PWM (Pulse Width Modulation).
To keep the hair dryer in place, use (just for this test) some double sided tape.
Step 5: Testing That Everything Works
For the asteroid I chose an air balloon, inflating it, until it has reached a diameter slightly smaller than the cylinder/water bottle (cut).
Initially, I painted the air balloon, but later I've realized it was too heavy.
After having inflated the "asteroid", I've tested the "hacked" hair dryer, checking that the DC motor wasn't getting too hot and that the fan had enough ventilation. As I mentioned at the beginning of this project, the protection for the fan of this hair dryer is very well designed, because it leaves a lot of space for the air intake.
Anyway, if any of the conditions above occur (especially if the fan doesn't have enough air intake), you must create some ventilation holes in the tray that supports the hair dryer.
Step 6: Power System, Camembert Cheese Support and Testing... Again!
You have also to create the power system for the hair dryer.
I chose 2 Lipos 2s (7.4V) 0.95mah Turnigy, connected in series (approx. 60 minutes of use before recharging them). As I mentioned at the beginning of this Instructable, this project requires a bit of electrical engineering skills.
You should buy a Y connector for Lipo Batteries (mine has the XT60 connectors), connecting the 2 Lipos in series
Remember that Lipo batteries are very dangerous; they can even cause fire.
Please do use all the necessary precautions when you use them:
i.e. Disconnect the Y connector before recharging the batteries.
You have now to make a support that will cover the power system.
To build it, I used as a sample the packaging for the Camembert cheese.
You will cut a foam board disc with the same diameter, making 2 "legs" of the same height of the Lipo batteries (of rectangular shape).
After this step, you should glue/fix the legs to the top of the turntable display.
The batteries will be trapped between the legs therefore they won't move.
Step 7: Lights, Electronics and Touch Sensors
I hacked the broken front light of my bike.
I removed the plastic support, I connected 2 wires (+/-) to a female plug and I placed the LED inside the top of a water bottle.
Before doing this operation, I painted them of the same color of the hair dryer.
For the touch sensors you have to connect the electronics to the landing pads, please follow the schematic.
Please check also my other Instructable, that explains how to make a DIY touch sensor, using 2 rubber bands and some kitchen foil.
You need to make 2 discs with a diameter slighter smaller than the top of the pastry cutter box and you have to cover the lower part of them, using some kitchen foil.
After this operation, you have to place the rubber bands inside the top of the pastry cutter box, making 4 holes and creating a bouncy (2/3mm) cross.
The electronics is composed by: a 555 Timer, a 5V micro relay, a mosfet IRFZ44N, 2 LEDs, some electrical wire and a 3.7V battery 250mah, that will power the relay.
Please follow the previous advices when you use the Lipo battery.
Later, using some foam board, I made a cover that hides all the electronics.
Step 8: Removable Hoops, Avocado Packaging and the Projector
To make the removable hoops, I've created a collar using 2 toilet paper rolls (that matches the diameter of the hair dryer).
I covered the collar using some pieces of packaging foam for the avocados, that is grey and has a futuristic shape.
Inside the collar I glued another piece of foam board (with UHU Por), to support better the hoops.
The hoops are 2 foam plates (I removed the central part from them), connected to the collar using some pop sickle sticks.
The material is very light. If the propellers (or the drone) hit them, nothing happens,
but If you don't have too much experience in flying mini/nano/micro drones, I do recommend to install the propellers guard... you know, just in case!
The projector is the one used as a car door welcome...
You can powering it using just one of the 2s (7.4V) Lipo batteries...
I repeat; one battery, soldering a JST Female connector to it.
Step 9: All Done!
Have fun with it, and again...
please do use all the precautions required.