ASIMO

Asimo is a humanoid robot designed and developed by Honda.It is a most complex but an accurate humanoid robot which learns from it's experience. Introduced on 21 October 2000, ASIMO was designed to be a multi-functional mobile assistant. With aspirations of helping those who lack full mobility, ASIMO is frequently used in demonstrations across the world to encourage the study of science and mathematics. At 130 cm (4 ft 3 in) tall and 48 kg (106 lb), ASIMO was designed to operate in real-world environments, with the ability to walk or run on two feet at speeds of up to 6 kilometres per hour (3.7 mph). In the USA, ASIMO is part of the Innoventions attraction at Disneyland and has been featured in a 15-minute show called "Say 'Hello' to Honda's ASIMO" since June 2005. The robot has made public appearances around the world, including the Consumer Electronics Show (CES), the Miraikan Museum and Honda Collection Hall in Japan, and the Ars Electronica festival in Austria.

Development history

Honda began developing humanoid robots in the 1980s, including several prototypes that preceded ASIMO. It was the company's goal to create a walking robot which could not only adapt and interact in human situations, but also improve the quality of life. The E0 was the first bipedal (two-legged) model produced as part of the Honda E series, which was an early experimental line of humanoid robots created between 1986 and 1993. This was followed by the Honda P series of robots produced from 1993 through 1997, which included the first self-regulating, humanoid walking robot with wireless movements.
The research conducted on the E- and P-series led to the creation of ASIMO. Development began at Honda's Wako Fundamental Technical Research Center in Japan in 1999 and ASIMO was unveiled in October 2000.
Differing from its predecessors, ASIMO was the first to incorporate predicted movement control, allowing for increased joint flexibility and a smoother, more human-like walking motion.Introduced in 2000, the first version of ASIMO was designed to function in a human environment, which would enable it to better assist people in real-world situations. Since then, several updated models have been produced to improve upon its original abilities of carrying out mobility assistance tasks. A new ASIMO was introduced in 2005, with an increased running speed to 3.7 mph, which is twice as fast as the original robot. ASIMO fell during an attempt to climb stairs at a presentation in Tokyo in December 2006, but then a month later, ASIMO demonstrated tasks such as kicking a football, running and walking up and down a set of steps at the Consumer Electronics Show in Las Vegas, Nevada.
In 2007, Honda updated ASIMO's intelligence technologies, enabling multiple ASIMO robots to work together in coordination. This version also introduced the ability to step aside when humans approach the robot and the ability to return to its charging unit upon sensing low battery levels.

Features and technology

 Form

ASIMO stands 130 cm (4 ft 3 in) tall and weighs 54 kg (119 lb). Research conducted by Honda found that the ideal height for a mobility assistant robot was between 120 cm and the height of an average adult, which is conducive to operating door knobs and light switches. ASIMO is powered by a rechargeable 51.8V lithium ion battery with an operating time of one hour. Switching from a nickel metal hydride in 2004 increased the amount of time ASIMO can operate before recharging. ASIMO has a three-dimensional computer processor that was created by Honda and consists of a three stacked die, a processor, a signal converter and memory. The computer that controls ASIMO's movement is housed in the robot's waist area and can be controlled by a PC, wireless controller, or voice commands.

Abilities

ASIMO has the ability to recognize moving objects, postures, gestures, its surrounding environment, sounds and faces, which enables it to interact with humans. The robot can detect the movements of multiple objects by using visual information captured by two camera "eyes" in its head and also determine distance and direction. This feature allows ASIMO to follow or face a person when approached. The robot interprets voice commands and human gestures, enabling it to recognize when a handshake is offered or when a person waves or points, and then respond accordingly. ASIMO's ability to distinguish between voices and other sounds allows it to identify its companions. ASIMO is able to respond to its name and recognizes sounds associated with a falling object or collision. This allows the robot to face a person when spoken to or look towards a sound. ASIMO responds to questions by nodding or providing a verbal answer and can recognize approximately 10 different faces and address them by name.

Mobility

ASIMO has a walking speed of 2.7 kilometres per hour (1.7 mph) and a running speed of 6 kilometres per hour (3.7 mph). Its movements are determined by floor reaction control and target Zero Moment Point control, which enables the robot to keep a firm stance and maintain position. ASIMO can adjust the length of its steps, body position, speed and the direction in which it is stepping. Its arms, hands, legs, waist and neck also have varying degrees of movement. The technology that allows the robot to maintain its balance was later used by Honda when it began the research and development project for its motorized unicycle, U3-X, in 2009. ASIMO has a total of 34 degrees of freedom. The neck, shoulder, wrist and hip joints each have three degrees of freedom, while each hand has four fingers and a thumb that have two degrees of freedom. Each ankle has two degrees of freedom, and the waist, knees and elbows each have one degree of freedom.

Impact and technologies

Honda's work with ASIMO led to further research on Walking Assist™ devices that resulted in innovations such as the Stride Management Assist and the Bodyweight Support Assist.
In honor of ASIMO's 10th anniversary in November 2010, Honda developed an application for the iPhone and Android smartphones called "Run with ASIMO." Users learn about the development of ASIMO by virtually walking the robot through the steps of a race and then sharing their lap times on Twitter and Facebook.

Specifications

Model	2000, 2001, 2002	2004	2005, 2007	2011
Mass	52 kg	54 kg		48 kg
Height	120 cm	130 cm		130 cm
Width	45 cm	45 cm		45 cm
Depth	44 cm	37 cm		34 cm
Walking speed	1.6 km/hour	2.5 km/hour	2.7 km/hour 1.6 km/hour (carrying 1 kg)
Running speed	–	3 km/hour	6 km/hour (straight) 5 km/hour (circling)	9 km/hour (straight)
Airborne time (Running motion)	–	0.05 seconds	0.08 seconds
Battery	Nickel metal hydride 38.4 V / 10 Ah/ 7.7 kg 4 hours to fully charge	Lithium ion 51.8 V / 6 kg 3 hours to fully charge
Continuous operating time	30 minutes	40 mins to 1 hour (walking)		1 hour (running/walking)
Degrees of Freedom	26 (head: 2, arm: 5×2, hand: 1×2, leg: 6×2)	34 (head: 3, arm: 7×2, hand: 2×2, torso: 1, leg: 6×2)		57 (head: 3, arm: 7×2, hand: 13×2, torso: 2, leg: 6×2)

 

Controlling and Powering ASIMO

ASIMO is not an autonomous robot. It can't enter a room and make decisions on its own about how to navigate. ASIMO either has to be programmed to do a specific job in a specific area that has markers that it understands, or it has to be manually controlled by a human.
ASIMO can be controlled by four methods:

• Wireless controller (sort of like a joystick)
• Gestures
• Voice commands

Using 802.11 wireless technology and a laptop or desktop computer, you can control ASIMO as well as see what ASIMO sees via its camera eyes. ASIMO can also use its PC connection to access the Internet and retrieve information for you, such as weather reports and news.
The wireless joystick controller operates ASIMO's movements the same way you would operate a remote-control car. You can make ASIMO go forward, backward, sideways, diagonally, turn in place, walk around a corner or run in circles. Making ASIMO move by remote control may not seem that advanced, but ASIMO does have the ability to self-adjust its steps. If you have it walk forward, and it encounters a slope or some sort of obstacle, ASIMO automatically adjusts its steps to accommodate the terrain.
ASIMO can recognize and react to several gestures and body postures, allowing users to command ASIMO nonverbally. You can point to a particular spot you want ASIMO to walk towards, for example, and it will follow your lead. If you wave to ASIMO, it will respond with a wave of its own. It can even recognize when you want to shake its hand.
ASIMO can understand and execute simple, preprogrammed verbal commands. The number of commands that can be programmed into its memory is practically unlimited. You can also have your voice registered in its programming, making it easier for ASIMO to recognize you.
In addition to the voice commands for controlling ASIMO's movements, there are also spoken commands to which ASIMO can respond verbally. This is the feature that has made it possible for ASIMO to work as a receptionist, greeting visitors and answering questions.
Like most other technologies in the robotics field, ASIMO is powered by servo motors. These are small but powerful motors with a rotating shaft that moves limbs or surfaces to a specific angle as directed by a controller. Once the motor has turned to the appropriate angle, it shuts off until it is instructed to turn again. For example, a servo may control the angle of a robot's arm joint, keeping it at the right angle until it needs to move, and then controlling that move. Servos use a position-sensing device (also called a digital decoder) to ensure that the shaft of the motor is in the right position. They usually use power proportional to the mechanical load they are carrying. A lightly loaded servo, for example, doesn't use much energy.
ASIMO has 34 servo motors in its body that move its torso, arms, hands, legs, feet, ankles and other moving parts. ASIMO manages a series of servo motors to control each kind of movement.
ASIMO is powered by a rechargeable, 51.8 volt lithium ion (Li-ION) battery that lasts for one hour on a single charge. The battery is stored in ASIMO's backpack and weighs about 13 pounds. ASIMO's battery takes three hours to fully charge, so a second (and third) battery is crucial if you needed ASIMO to operate for very long. Users can charge the battery onboard ASIMO through a power connection or remove the backpack to charge separately.

 

ASIMO's Motion: Walk Like a Human

Honda researchers began by studying the legs of insects, mammals, and the motion of a mountain climber with prosthetic legs to better understand the physiology and all of the things that take place when we walk -- particularly in the joints. For example, the fact that we shift our weight using our bodies and especially our arms in order to balance was very important in getting ASIMO's walking mechanism right. The fact that we have toes that help with our balance was also taken into consideration: ASIMO actually has soft projections on its feet that play a similar role to the one our toes play when we walk. This soft material also absorbs impact on the joints, just as our soft tissues do when we walk.
ASIMO has hip, knee, and foot joints. Robots have joints that researchers refer to as "degrees of freedom." A single degree of freedom allows movement either right and left or up and down. ASIMO has 34 degrees of freedom spread over different points of its body in order to allow it to move freely. There are three degrees of freedom in ASIMO's neck, seven on each arm and six on each leg. The number of degrees of freedom necessary for ASIMO's legs was decided by measuring human joint movement while walking on flat ground, climbing stairs and running.
ASIMO also has a speed sensor and a gyroscope sensor mounted on its body. They perform the tasks of:

• sensing the position of ASIMO's body and the speed at which it is moving
• relaying adjustments for balance to the central computer

These sensors work similarly to our inner ears in the way they maintain balance and orientation.
ASIMO also has floor surface sensors in its feet and six ultrasonic sensors in its midsection. These sensors enhance ASIMO's ability to interact with its environment by detecting objects around ASIMO and comparing gathered information with maps of the area stored in ASIMO's memory.
To accomplish the job our muscles and skin do in sensing muscle power, pressure and joint angles, ASIMO has both joint-angle sensors and a six-axis force sensor.

Unless you know a lot about robotics, you may not fully grasp the incredible milestone it is that ASIMO walks as we do. The most significant part of ASIMO's walk is the turning capabilities. Rather than having to stop and shuffle, stop and shuffle, and stop and shuffle into a new direction, ASIMO leans and smoothly turns just like a human. ASIMO can also self-adjust its steps in case it stumbles, is pushed, or otherwise encounters something that alters normal walking.
In order to accomplish this, ASIMO's engineers had to find a way to work with the inertial forces created when walking. For example, the earth's gravity creates a force, as does the speed at which you walk. Those two forces are called the "total inertial force." There is also the force created when your foot connects with the ground, called the "ground reaction force." These forces have to balance out, and posture has to work to make it happen. This is called the "zero moment point" (ZMP).
To control ASIMO's posture, engineers worked on three areas of control:

• Floor reaction control means that the soles of the feet absorb floor unevenness while still maintaining a firm stance.
• Target ZMP control means that when ASIMO can't stand firmly and its body begins to fall forward, it maintains position by moving its upper body in the direction opposite the impending fall. At the same time, it speeds up its walking to quickly counterbalance the fall.
• Foot-planting location control kicks in when the target ZMP control has been activated. It adjusts the length of the step to regain the right relationship between the position and speed of the body and the length of the step.
  

  ASIMO's Motion: Smooth Moves

  ASIMO can sense falling movements and react to them quickly; but ASIMO's engineers wanted more. They wanted the robot to have a smooth gait as well as do something that other robots can't do -- turn without stopping.
  
  
  
  When we walk around corners, we shift our center of gravity into the turn. ASIMO uses a technology called "predictive movement control," also called Honda's Intelligent Real-Time Flexible Walking Technology or I-Walk, to accomplish that same thing. ASIMO predicts how much it should shift its center of gravity to the inside of the turn and how long that shift should be maintained. Because this technology works in real time, ASIMO can do this without stopping between steps, which other robots must do.
  Essentially, with every step ASIMO takes, it has to determine its inertia and then predict how its weight needs to be shifted for the next step in order to walk and turn smoothly. It adjusts any of the following factors in order to maintain the right position:
  
  • the length of its steps
  • its body position
  • its speed
  • the direction in which it is stepping
  While reproducing a human-like walk is an amazing achievement, ASIMO can now run at speeds up to 3.7 miles per hour (6 kilometers per hour). In order to qualify as a true running robot, ASIMO must have both feet off the ground for an instant in each step. ASIMO manages to be airborne for .08 seconds with each step while running.
  Honda engineers encountered an entirely new set of challenges while trying to give ASIMO the ability to run. They gave ASIMO’s torso a degree of freedom to aid in bending and twisting so that the robot could adjust its posture while airborne. Without this ability, ASIMO would lose control while airborne, possibly spinning in the air or tripping when landing.
  In order to make turns smoothly while running, the engineers enhanced ASIMO's ability to tilt its center of gravity inside turns to maintain balance and counteract centrifugal force. ASIMO could even anticipate turns and begin to lean into them before starting the turn, much like you would if you were skiing or skating.
  In the next section, we’ll look at how ASIMO is able to recognize images and sense its environment.