If you’ve been in this industry a while you may remember the IBM Simon or the Apple Newton, both great ideas for products, but unfortunately, the technology just wasn’t capable of fulfilling the promise that these product designers had in mind. The holidays provide a unique opportunity to reflect. They also simultaneously create an environment for an impulse buy proceeded by a pause every year to play with my kids (now 21 and 24). 2017 was no different, and so this year for the first time ever I picked up not one but three quadcopter drones. After dinner Christmas day, all three were simultaneous buzzing around our empty two car garage attempting to take down several foam rubber cubes balanced on the garage door opener return beam. Perhaps I should bound this a bit more, a week earlier I’d spent $25 on each of the kid’s drones, not knowing if they would even interested, and $50 on my own. We had a blast, and if you’ve not flown one you should really splurge and spend $50 for something like the Kidcia unit, it’s practically indestructible. On the downside, the rechargeable lithium batteries only last about eight minutes, so I strongly suggest purchasing several extra batteries and the optional controller.
During the past week since these purchases, but before flying, I’ve wondered several times why we haven’t seen life-sized quad-copter drones deployed in practical real-world applications? It turns out this problem has waited 110 years for the technology. Yes, the quadcopter or rotary wing aircraft was first conceived, designed and demonstrated, in tethered flight mode back in 1907. The moment you fly one of today’s quadcopters you quickly realize why they flew in tethered flight mode back in 1907, crashing is often synonymous with a landing. These small drones, mine has folding arms and dual hinged propellers, take an enormous beating and still continue to fly as if nothing happened. We put at least a dozen flights on each of the three drones on Christmas day, and we’ve yet to break a single propeller. Some of the newer, more costly units, now include collision avoidance, which may actually take some of the fun away. So back to the problem at hand, why has it taken the quadcopter over 110 years to gain any traction beyond concept? Five reasons stand out, all technological, that have made this invention finally possible:
- Considerably computing power & sophisticated programming in a single ultra-low power chip
- Six-axis solid-state motion sensors (3-axis gyroscope, 3-axis accelerometer) also on a single ultra-low power chip
- Very high precision, efficient, compact lightweight electric motors
- Compact highly efficient energy storage in the form of lithium batteries
- Extremely low mass, highly durable, yet flexible propellers
That first tethered quadcopter back in 1907 achieved only two feet of altitude while flown by a single pilot and powered by a single motor with four pairs of propellers. Two of the pairs of propellers were counter-rotating to eliminate the effects of torque, and four men, aside from the pilot, were required to keep the craft steady. Clearly far too many dynamically changing variables for a single person to process. Today’s quadcopter drones have an onboard computer that continuously adjusts all four motors independently while measuring the motion of the craft in six axises and detecting changes in altitude (via another sensor). The result is that when a drone is properly setup it can be flown indoors and raised to any arbitrary altitude where it will remain hovering in place until the battery is exhausted. Once the pilot requests the drone move left to right, all four rotors speeds are independently adjusted via the onboard computer to keep the drone from rotating or losing altitude. Controlled flight of a rotary wing craft, whether a drone or a flying car, requires considerable sensor input, and enormous computational power.
Petroleum-powered quadcopters are available, but to overcome issues in the variations of engine speeds and latency, the time from sensor input to action, they often utilize variable pitch propellers with electronic actuators. These actuators allow for rapid, and subtle changes in propeller pitch adjusting for variable inputs from the sensors and the pilot. While gas-powered drones often provide greater thrust, for most applications modern drones are assembled using electronic motors. These electric motors are extremely efficient, respond rapidly to subtle changes in voltage by delivering predictable rotational speeds, all while being very lightweight. Coupled with highly efficient lithium batteries, these make for an ideal platform for building drones.
The final component making these drones possible are advanced plastics and carbon fiber that now provide for very light-weight propellers that can take considerable abuse without fracturing or failing. When I grew up in the late 1960s and early 70s it didn’t take much to break that rubber band powered red plastic propeller that came with balsa wood planes of that era. Today I can crash my drone into the garage door at nearly full speed and all eight propeller blades remain scratch free.
So next time you interact with a product and wonder why it doesn’t perform to your expectations, perhaps the technology has still not caught up to the intent of the product designers. Happy Holidays.