How Does the Micro Mosquito Fly?
Now that you know how a normal helicopter is designed, you can appreciate the obstacles that the creators of the Micro Mosquito had to overcome. It is possible to purchase a remote control helicopter that includes most of the complexities of a real helicopter. However, these mechanical toys will cost you at least $1,000, which you will most certainly crash and destroy within a few hours. So, how does the Micro helicopter do it for a fraction of the cost?
First, the Micro is not a true three-dimensional flier like a real helicopter. To properly represent a real copter, it would take six different controls (also known as six channels). The Micro only has three channels, but this is enough to emulate most of the functionality of a real helicopter. The first channel is directly tied to the speed of the blades, which increase or decrease the lift. As we discussed earlier, changing the speed of the rotor to control elevation is not a good idea for a conventional helicopter, but in the case of the Micro, it works perfectly.
The most obvious difference between a real helicopter and the radio-controlled (RC) version is that it has two blades instead of the normal one. What you may not notice about these blades is they are actually connected to two separate rotors, which are then connected to separate motors via the odd-looking gearing mechanism. Recall that a normal helicopter has only one main rotor, which creates torque and thus necessitates the tail rotor to keep the helicopter from spinning out of control. In the case of the Micro, the tail rotor blade is mounted horizontally, which means it can't be used to prevent the torque forces (see Figure 1).
Figure 1 Helicopter and controller.
Instead, Interactive Toy Concepts nullified the net torque by using two rotors that spin in opposite directions. The end result is that the torque from the one rotor is negated by the torque of the other rotor. Because the Micro is much more sensitive to things like battery power and normal wear and tear, the designers also included a small knob in the center of the controller to allow the user to manually tweak the speed of the lower rotor to match the speed of the upper rotor. This keeps the blades in sync, thus preventing the spin.
While keeping the helicopter straight is amusing, it would be much more amusing if the toy could spin in the air while moving forward. This spinning functionality is handled by the second channel of the remote, which basically speeds up and slows down one main rotor motor, thus creating a slight torque that then causes the spinning effect. Moving the controller back to the center reduces the variance and stops the spin. This is the same channel that is used by the center knob to keep the Micro from spinning while hovering.
So, how does the Micro move forward and backward? If you look at the tail rotor, you can see that it looks like a mini-blade and produces a small breeze when operated (see Figure 2). This is the third channel of the remote. It either sucks the backend down, which causes the helicopter to drift backward, or lifts the backend up, which causes the helicopter to slide forward. To help increase the forward motion of the Micro, you can add extra weights under each of the main motors (see Figure 3). This changes the center of balance for the entire device, and helps to tilt the helicopter forward at a deeper angle, which increases the forward momentum.
Figure 2 Tail rotor.
Figure 3 Extra weights for improved forward motion.
In other words, the Micro creators emulated a conventional helicopter using some clever techniques. And because the design includes few parts that can break, the copter will survive crash after crash after crash (as the crash video illustrates). After a hard crash, you might have to realign the rotor gear with the motor head gear, as these often slip off. If you do break the main rotor assembly, RadioShack has replacement parts for your consumption. However, I have had my helicopter for about a month and am still using the same set of blades.