liveforphysics
100 TW
Ok, now that we've finished the TTXGP and hillclimb bike builds, I will have time to go visit this place finally. lol
Joby's headquarters are tucked into the redwoods of the Santa Cruz Mountains, not far from the test site. The lodge-like main building is encased by tall windows and trussed with dark Âwooden beams; outside, there's a deck with barbecues and umbrella-topped tables, a shady lawn and a large organic garden. The place is patrolled by friendly dogs and catered by gourmet chefs, creating a vibe that's less corporate headquarters and more high-end yoga retreat.
Bevirt is pinballing around the grounds when I arrive. He jogs downhill to the warehouse, calling out questions to colleagues and striding between lathes, mills and other shop tools. The 37-year-old has been on the go from an early age: As a high school cycling Âfanatic, he designed and built several bikes; during college he worked as an engineer and saved $50,000, which he invested in the stock market.
By the end of the 1990s, after earning a master's degree in mechanical engineering at Stanford University, he cashed out a $500,000 portfolio and seeded his first business, the laboratory-equipment manufacturer Velocity11, and then Joby, Inc., which makes the GorillaPod line of flexible tripods. These successes gave him the capital to launch Joby Energy, as well as an aviation company. Joby Energy is a project of environmental passion, but it's also a business. "Energy is just a commodity—one electron is no better than another," he says. "What matters is the cost."
Ground-based wind turbines don't spin at full speed every minute of every day. Sometimes the wind blows weakly; sometimes not at all. That's why conventional Âwindmills generate only up to about one-third of their theoretical full power. But the wind where many airborne companies want to fly, at an altitude of about 1300 feet, Âtypically blows more consistently and one and a half to three times faster than at the earth's surface. That means airborne wind could run at a projected capacity factor of 70 percent, Bevirt says—twice the efficiency of terrestrial wind.
JoeBen Bevirt is an extraordinary individual – and that’s no hyperbole. Creating a lucrative underpinning with his line of knobby, infinitely-adjustable tripods, cell-phone and iPad™ holders, and LED lights, he has expanded into designing giant kites to fly into upper-atmosphere winds and generate high-output electricity.
To loft these kites, he has created a line of motors with the aid of Diederick Marius, shown on the Joby Motors web site, and so far include two versions each of the JM1S and JM2S. Each can be configured with different windings for different applications.
The JM1S weighs 1.8 kilograms (3.96 pounds) and can put out 12 kilowatts peak (16 horsepower) at 6,000 rpm. Diminutive, it is only154 millimeters in diameter (6.06 inches) and 53 mm (2.08 inches) thick. Although recommended usage includes radio-controlled models, one can see electric ultralight aircraft being designed in enthusiasts’ heads. Prices are $895 and $955 for the two configurations of the motor.
The larger JM2S weighs 3.35 kg (7.37 pounds), and produces 15 kW peak (20.1 hp) at 2,500 rpm. Prices start at $1,099.
Both motors feature 10,000-hour dual bearings, a characteristic anodized alloy outer ring (stator) and 22 poles (JM1S) or 46 (JM2S). Drop the “S†from the designation and each motor becomes a little thicker and heavier, draws a few more Amps, and puts out more power and torque.
The JM1S twists 13 Newton-meters, or 9.58 foot-pounds continuously, while the JM1 exerts 21 N-m (15.49 ft-lb.). The JM2S manages 40 N-m (29.5 ft-lb.) and the JM2 produces 53 N-m (39 ft-lb.), all impressive for such small motors.
With these light, torquey little units available, what’s an intrepid designer to do? Make a vertical takeoff and landing vehicle to shorten the daily commute – of course! JoeBen announced his Monarch Personal Air Vehicle (PAV) at this year’s Electric Aircraft Symposium in Santa Rosa, California on April 29 and caught a lot of attention with his animated video of the eight-motor craft levitating, climbing, travelling and landing in a depiction of a perfect commute.
Such technology in the hands of amateur pilots will require a lot of automation (know anyone with an eight-engined multi checkout?) which Joby is capable of managing. Note the $550 autopilot on their Robotics page.
https://www.jobyrobotics.com/category.php?id_category=5
The prototype is under construction at Windward Performance in Bend, Oregon, with designer Greg Cole making almost everything but the motors and controllers in house (that may explain the resemblance to the SparrowHawk sailplane). Although JoeBen did not mention pricing in his CAFE talk, an earlier presentation mentioned a price under $30,000, possible with the low cost of the motors and automation available if volume production took off, but obviously not with batteries. He has also mentioned going 100 miles for a $1.00 recharge. If that doesn’t get people out of their cars, what will?
One extension of such technology would be the need to revamp our outdated air traffic control system into a more flexible, dynamic entity, all the more reason to hope for JoeBen’s success.
could you ask about wider stacks and water cooling? both will be needed for our motorcycle projects. merci, rolfliveforphysics said:Ok, ...I will have time to go visit this place finally. lol
OK Luke, got any pics - want to tell us more?liveforphysics said:Ok, now that we've finished the TTXGP...
regmeister said:Did you meet Diederik? He told me they are building controllers in house, but hasn't provided much for details.
http://newsletter.jobyenergy.com/public/q1_2010/features/04.php
Lock said:I'm beginning to think Luke and party had to sign a NDA for the tour :wink:
jonescg said:Wow. You call that a rotor? THIS is a rotor!
Interesting - for applications like aeroplanes or other large framed items the bigger the radius the more power. Is it just too difficult to stack more rotors for more power? Cooling would be the issue I guess? I'm just wondering why all of these BL motors seem to stop at 12-15 kW, and if they go higher it's all about bigger diameters, not depth.
johnrobholmes said:It isn't too difficult to stack more rotors on an inrunner. Going larger diameter is a smart move though, it reduces geardown losses.
Drooooool over that largest motor. Frickin WHEEL motor!