The company, Segway LLC [now Inc.], was founded on July 27th 1999 with the vision to develop highly-efficient, zero-emission transportation solutions using dynamic stabilization technology. The company's first product to market was the model "i167" (i Series) Segway Human Transporter (HT), the first two-wheeled, self-balancing, electric transportation device to use Kamen's patented dynamic stabilization technology. The Segway Human Transporter (HT) i Series model i167 was the company's best-known product, a result of years of research and development led by Kamen with the goal of building something that would make a unique and lasting contribution to society.
The Segway HT i167 (code-name, "Ginger") reflected Dean's belief that science and engineering can be harnessed to improve people's daily lives and community. HT, for human transporter, needs little explanation, yet the name "i Series" is not as well-defined. The letter "i" seems to have been an abbreviation for "industrial" or "industry" to support its heavy-duty nature of construction, and the fact it was designed for use on factory floors in manufacturing facilities, and to be marketed for sale as fleets used in the corporate world. The 167 was a reference the the 67% greater battery life it had compared to earlier ones tested with NiCad batteries. Segway promised a less expensive model for "the rest of us" (regular people) would soon follow. The Segway HT is designed to reduce the need for cars and other vehicles with combustion engines. This could produce some profound environmental changes -both in the long and short term (learn more about this on "Dean's idea for HT" or Segway.com).
In our tests, we rode the Segway HT in a variety of indoor and outdoor environments. Zipping along on the little platform was so steady and comfortable, we quickly forgot how much technology was at work to keep us balanced. The Segway HT moves forward with cues from your body language--the subtle leaning you use to balance yourself while walking or running. When you lean forward, the Segway HT goes forward. A walking lean produces a walking rate, a steeper running lean can bring the machine to its top speed of 12.5 mph. The Segway HT stops when you right yourself again. Steering is controlled separately with a small twist-grip on the left handlebar. The Segway HT's two-wheeled design makes it quite agile--it can do sharp turns and turn completely in place. Sharper turns require slight leaning into the turns, as you'd expect, but the Segway HT helps by actively regulating turn responsiveness based on your speed. One small complaint: using a throttle-like control for turns instead of acceleration did take some getting used to, but the inconvenience was minor and went away over time. Overall, we were surprised how quickly we were able to get comfortable on the Segway HT. A novice can be underway in seconds (with supervision) and ascending ramps and turning figure eights in minutes. After training and a few hours of use, a rider should feel comfortable with a wide range of activities.
The Segway HT moves briskly along on both paved and rough terrain, taking ruts and potholes bumpily but with no loss of control, even for the beginner. Modest hills were ascended with ease and without much discernable effort. All things told, the Segway HT seemed rugged enough to provide reliable transportation in pedestrian environments ranging from rural trails to the sidewalks of a congested city. And utility aside, it's worth stating that the element of machine-assisted balance was a continuous delight. We simply had more control over our movements than we previously could have imagined possible. This was particularly true on downhill rides, where our body language had a degree of command over gravity so unusual that it produced a dreamy, floating feeling. The Segway HT is not a medical device; if you can't easily stand upright or endure some jostling on varied terrain, it will not solve these problems for you. But while the Segway HT cannot provide balance that the rider doesn't already have, its responsiveness brings a subtle beauty to the rider's movements. We watched more experienced riders start, stop, swoop, and turn as gracefully as figure skaters. In fact, the machine's ease of use could create some overconfidence. The Segway HT has not suspended the laws of physics--its wheels need traction. While the machine will keep itself level under almost any situation we could imagine, a careless rider who drops a wheel over a curb, or tries to turn too quickly on a slippery surface, certainly could take a tumble. Segway advises that riders wear a safety helmet (like a bicycle helmet) and start out in the Beginner mode before moving on to the faster settings.
The Segway HT's controls are simple. A single round display on the handlebars shows either a smiley face (meaning "get on") or a frown face ("get off"). A graphic surrounding the face indicates the battery level. The Segway has no brakes--slowing down involves the same process as acceleration--and its gentle rate precludes any need for a speedometer. We timed its startup speed from the off position to ready to ride: pressing an encrypted "key" to the key port (the key looks like a large watch battery on a plastic fob), hitting the start button, and waiting for the smiley face to come up took a little more than one second. This machine is clearly designed for close interaction with pedestrians. Its footprint is only a bit wider than a large man, so we were able to do things like ride comfortably in an elevator with another Segway HT rider and a pedestrian, with an almost disappointing lack of bustle or incident. The machine can haul 75 pounds of cargo and still support a 250-pound person, though you'll need to use the HT's soon-to-come mounted accessory bags for any serious buying trip.
Having ridden a Segway HT, we think almost anyone would be delighted to try this machine. Inevitably, however, one must ask about how usable it is. Clearly, it isn't a car: it won't carry multiple passengers or much luggage, go long distances, or protect you from the elements. Still, we thought of many circumstances where the Segway HT could be a fun and practical alternative to other modes of transportation. We can see potential users as regular folks traveling to and from work each day, students and professors in college towns, city dwellers who take many short trips, retirees in Sunbelt resort communities, vacationers traveling with RVs, and people with easy access to nature trails and walkways.
We had the opportunity to look into the guts of the Segway HT in its pre-assembled state. Inside it was clean and simple, and the few moving parts, such as the gears, struck us as rugged and well made. There are no cooling fans; the circuits and engine are cooled through their contact with the platform's heat-drawing aluminum casing. Each finished HT is tested both at the software level and for quality riding on an obstacle course in the assembly plant. See the technical specifications for more information.
We're convinced that anyone who tries a Segway HT will be smiling in minutes. The other advantage is that early purchasers will certainly be the first on their blocks to have one. But for how long? We think we'll all be seeing much more of the Segway HT in the future.
-Very high build quality
-Environmentally friendly, extremely energy efficient
-Requires little storage space
-Newness factor--you've never ridden anything like this before
-Fun to ride, and looks cool
-Purchase price may be prohibitive for many potential users, though the cost is partially offset long term by nominal upkeep
-Laws regarding legal riding areas (sidewalk versus street) vary from state to state
-Minor inconvenience: rubber plug-in protectors on the machines seemed a bit loose, flopping around a bit on the more rigorously used machines, inconsistent with generally excellent build standards
-Accessories, like carrying bags and lights, will not be available until spring 2003
-Top speed: 12.5 miles per hour (20 kph). This is about three times typical walking speed.
-Weight: 83 lbs (38 kg)
-Width: The Segway's footprint (how much space it covers on the ground) is 19 by 25 inches (48 by 63.5 cm). This makes the Segway about the same width as an average size person, so it doesn't take up much space on the street. The platform is 8.3 inches (21 cm) off the ground.
-Weight capacity: Maximum payload 260 pounds (118 kg) which is a combination of rider and cargo. Rider should be in the 100-250 pound range (110 kg), with up to 75 pounds (34 kg) of cargo.
-Range: About 8-12 miles (13-19 km) on even ground, with a single charge. Operating temperature between 32F -122F (0-50C).
-Driver interface: The Segway has a small multicolor LCD screen that tells the driver how much battery power is left and how well the vehicle is functioning. The screen displays a cartoon face, which expresses the general condition of the vehicle. The driver interface is designed to be simple and intuitive.
-Motors: Each of the Segway's wheels is driven by a 2-horsepower electric motor that produce no emissions.
-Transmission: The two-stage transmission, built by Segway and Axicon Technologies, has a compact 24:1 gear ratio. It uses a helical gear assembly that significantly reduces noise. The Segway team configured the two meshes in the gear box (the points where gears connect) to make sound exactly two octaves apart. This means the sounds are in harmony, so the gear box make a more musical noise. The gears are also designed to have noninteger gear ratios, meaning the gear teeth mesh at different points from revolution to revolution. This minimizes wear and tear to extend the life of the gear box.
-Computer: The Segway's brain is made up of two circuit boards, housed in the vehicle's chassis. The circuit boards, which boast a total of 10 microprocessors, normally work together, but each can function independently in the event of a computer problem. If one breaks, the other circuit board will slow the vehicle down gradually to avoid an accident.
-Power: The Segway is powered by two rechargeable batteries. Segways were expected to come with either nickel cadmium (NiCd) or nickel metal hydride (NIMH) batteries, yet i167 models shipped only with NiMH batteries. The batteries are constantly monitored by a circuit board, which communicates any performance problems to the central brain. The batteries can be recharged with household AC current. Dean Kamen estimates a Segway would cost somewhere around 5 cents a day in electricity bills.
-Sensors: The Segway uses five gyroscopes and a collection of other tilt sensors to keep itself upright. Only three gyroscopes are needed -- the extra sensors are included as a safety precaution. The Segway has an additional weight sensor built into its platform to tell the computer when a rider has stepped on.
-Brakes: The Segway doesn't have a formal braking system. To stop, the rider stands upright without leaning forward or backward, and the vehicle maintains its position.
-Turning radius: Since it only has two wheels, the Segway can rotate around a single axis (the wheels turn in opposite directions). This gives the Segway a turning radius of zero.
-Wheels: The Segway wheel consists of a forged steel wheel hub with a glass-reinforced thermoplastic rim. Each wheel is secured to the drive shaft with a single nut. The tires are made of a silica compound, which provides good traction even on wet surfaces.
-Security: The Segway uses an electronic key system. The key, which looks something like a car lighter, stores a 128-bit encrypted digital code. The vehicle won't start unless the key is plugged into its port. The key can also store settings for vehicle operation. Segways include one key (black) for "beginner mode," where the vehicle has a lower maximum speed and slower turning rotation, an intermediate (yellow) key, and one key (red) for "experienced mode." Segway plans to offer programmable keys down the road, which well let users store particular operation settings.
-Chassis: The Segway's sensitive electronic equipment is housed in a sturdy die-cast aluminum chassis. According to Segway, the chassis can withstand 7 tons of force.
-Control shaft: The aluminum shaft that holds up the Segway's handlebars can be adjusted to different heights. Riders can attach clips to the shaft to carry bags or other cargo.
Click here to view an interactive diagram of the Segway HT i167 and its parts.