Mind-Boggling Medical Technologies

If tiny robots crawling along the inside of a blood vessel sounds like something from a sci-fi thriller, think again. Blood bots, along with other amazing medical technologies, are in development now and provide promise for early diagnosis and treatment of a variety of medical conditions. In the not-too-distant future, you or a family member may benefit from the medical advances on the horizon.
Note: Many of the innovations discussed are still in the early stages of development. MSN Health & Fitness does not endorse or recommend any products, treatments or procedures in this presentation.
Blood bots
A robot barely visible to the eye may make scalpels a thing of the past for biopsies and blood-vessel repairs. Surgeons first inject these mechanical critters into a patient's vein. Once the device is inside the bloodstream, operators use a magnetic field to guide the tiny robot—it's just 1 millimeter in diameter—to its destination. There the bot can clean plaque-filled vessels like a Roto-Rooter and can even slice off tissue for biopsies. Because the bot, also called the "ViRob," makes deep incisions unnecessary, it reduces recovery time for the patient. It's also possible that physicians may be able to direct the bot from a remote location to operate on patients in the comfort of their own home in the future. Oded Salomon, an engineer at the Technion-Israel Institute of Technology in Haifa, Israel, and the developer of the bot, has said he believes it will be in use by specialists within five years.

Korea to build magic kingdom for robots

The robot magic kingdom will be part of a giant residential and industrial complex called Robot Land in Incheon, one of South Korea's largest cities and a major transportation hub.

According to the Robot Land Web site, the theme park will feature all manner of robot entertainment, including exhibitions of robot characters from films and cartoons; reconstructions of robot-oriented movie sets like "Minority Report," "I,Robot," and "Matrix"; a robotic-arm ride; an aquarium where visitors can watch and manipulate robotic fish; and even droid cashiers and performers.

A theme park shopping area will likely feature robots operating as cashiers.
(Credit: Robot Land)

After a bidding process lasting several years, the Korean government has just authorized Incheon to build the park, which will cost 784.5 billion won (about $687 million), with $596 million coming from private investors, about $46 million from the central government, and about $46 million from the local government, according to the Korea Herald.

Construction is set to begin this year and is expected to be completed in 2013, with some parts of the facility opening in 2012, officials from Korea's Ministry of Knowledge Economy said.

Besides rides and Robocop look-alikes, the roughly 110-acre Incheon Robot Land will house residential complexes, office buildings, a Seoul National University robotics research center, a stadium for robotics competitions, and robot-themed shopping centers. The entire Robot Land is expected to attract 2.8 million visitors annually, boosting the local economy by creating some 18,000 related jobs in the theme park alone, ministry officials said.

The robotics industry in Korea, considered a leader in the field, was valued at an estimated $770 million in 2009, according to Telecoms Korea, up about 10 percent from 2008. The country has spawned a number of notable bots, namely Hubo, a smiling, blinking humanoid with the face of Albert Einstein. Others include the Hoya mini firefighter helper bot and Mahru-Z, a housemaid bot that does laundry.

all you need to know about robots....

what's new from japan


snake-like robots

---
souryu
snake robots are also known as serpentine robots.
as the name suggests, these robots possess multiple actuated
joints thus mulitple degrees of freedom.
this gives them superior ability to flex, reach, and approach a
huge volume in its workspace with infinte number of configurations.
this redundance in configurations gives them the technical name:
hyper redundant robots. ideally, the future snake design will
consist of three degree of freedom stages - roll, pitch, and extension.
souryu or blue dragon, is a remote-controlled robot designed by
tokyo institute of technology's professor shigeo hirose.
the snake-like souryu crawls using six tracks, two on each
side of its three-part body. it is equipped with a camera
and microphone to search for victims, and can bend at
the joints or roll over on its side to maneuver through rubble.

---
ACM-R3
the first successful mechanical snake was also developed
by professor shigeo hirose.
the active cord mechanism consisted of 13-links.



spider-like robots

---
comet III
was designed by chiba university professor kenzo nonami, and
is part of a state-funded project to develop de-mining technologies
for afghanistan. four metres long and weighing one tonne,
the comet III walks on six sturdy metal legs.
an additional limb in front is equipped with a metal
detector and radar to find mines, while a second sprays
paint on the ground to mark the spot.



legged-walking robots

---
yambo III
one of the moving and task performing robots,
the legged-walking type, which has high terrain adaptability,
is yambo III. generally walking robots need so many degrees
of freedom (DOF) that robots become heavy and its mechanism
become more complicated. one of the effective solutions to
these problems is developing the robot with bipedal configuration.

---
morph 3
officials and researchers in japan, home to almost half
the world's 756,000 industrial robots, hope a new robot
industry will give the stagnant economy a boost.
japanese researchers want to advance the technology
by improving mobility or making robots more autonomous.
morph 3, a 38-cm-tall humanoid robot, tries to stand
after being laid on its back during an experiment at the
chiba institute of technology in narashino, chiba prefecture.
the project is a joint project between kitano symbiotic system
project and leading edge design corp.
athletic properties of the robot become the highest among
the same size robots in the world.
the robot appeared on the stage of robocup 2002 held in
fukuoka, japan.

---
cyclops
is an interactive human-shaped machine. the machine is
equipped with a single camera eye and a spinal column
structure. this work was developed for 'robot meme exhibition'
at the national museum of innovative technology and
emerging science, tokyo, in 2001. cyclops was shown in
september 2002at ars electronica center in linz, austria as a
part of its permanent exhibition.

---
DB
an expert in brain science, kawato developed the DB,
a humanoid robot that can imitate human action, based on his
knowledge that the cerebellum plays a key role in learning
and memory. however, the robot has managed to learn only
24 kinds of human action over three years.

---
atom
japanese researchers are advocating a grand project,
under which the government would spend 50 billion
yen a year over three decades to develop a humanoid
robot with the mental, physical and emotional capacity
of a 5-year-old human - the atom project.

'most of today's robots operate with a program written by
humans. in order to develop a robot that can think and
move like a 5-year-old, we have to first understand the
mechanism of how human brains work,' mitsuo kawato,
chief of the computational neuroscience laboratories
at the kyoto-based advanced telecommunications
research institute internationa said, admitting the difficulty
of his project. 'that will be equal to understanding
human beings.'

tthe project was inspired by the popular robot animation series
'tetsuwan atom' by the late cartoonist osamu tezuka
(unlike cartoonist tezuka's 'atom' character, known as
'astro boy' overseas, based on an image of a 9-year-old
boy, the atom project aims to create a humanoid robot
with the physical, intellectual and emotional capacity of
a 5-year-old that would be able to think and move on its
own). the researchers say it would help promote scientific
and technological advances in japan, just like the u.s.
apollo project, which not only succeeded in landing men
on the moon but contributed to a broad range of technological
breakthroughs - a project of this magnitude would inject
much-needed vigor into a nation depressed from years of
economic slump.

all you need to know about robots....

what's new from japan


snake-like robots

---
souryu
snake robots are also known as serpentine robots.
as the name suggests, these robots possess multiple actuated
joints thus mulitple degrees of freedom.
this gives them superior ability to flex, reach, and approach a
huge volume in its workspace with infinte number of configurations.
this redundance in configurations gives them the technical name:
hyper redundant robots. ideally, the future snake design will
consist of three degree of freedom stages - roll, pitch, and extension.
souryu or blue dragon, is a remote-controlled robot designed by
tokyo institute of technology's professor shigeo hirose.
the snake-like souryu crawls using six tracks, two on each
side of its three-part body. it is equipped with a camera
and microphone to search for victims, and can bend at
the joints or roll over on its side to maneuver through rubble.

---
ACM-R3
the first successful mechanical snake was also developed
by professor shigeo hirose.
the active cord mechanism consisted of 13-links.



spider-like robots

---
comet III
was designed by chiba university professor kenzo nonami, and
is part of a state-funded project to develop de-mining technologies
for afghanistan. four metres long and weighing one tonne,
the comet III walks on six sturdy metal legs.
an additional limb in front is equipped with a metal
detector and radar to find mines, while a second sprays
paint on the ground to mark the spot.



legged-walking robots

---
yambo III
one of the moving and task performing robots,
the legged-walking type, which has high terrain adaptability,
is yambo III. generally walking robots need so many degrees
of freedom (DOF) that robots become heavy and its mechanism
become more complicated. one of the effective solutions to
these problems is developing the robot with bipedal configuration.

---
morph 3
officials and researchers in japan, home to almost half
the world's 756,000 industrial robots, hope a new robot
industry will give the stagnant economy a boost.
japanese researchers want to advance the technology
by improving mobility or making robots more autonomous.
morph 3, a 38-cm-tall humanoid robot, tries to stand
after being laid on its back during an experiment at the
chiba institute of technology in narashino, chiba prefecture.
the project is a joint project between kitano symbiotic system
project and leading edge design corp.
athletic properties of the robot become the highest among
the same size robots in the world.
the robot appeared on the stage of robocup 2002 held in
fukuoka, japan.

---
cyclops
is an interactive human-shaped machine. the machine is
equipped with a single camera eye and a spinal column
structure. this work was developed for 'robot meme exhibition'
at the national museum of innovative technology and
emerging science, tokyo, in 2001. cyclops was shown in
september 2002at ars electronica center in linz, austria as a
part of its permanent exhibition.

---
DB
an expert in brain science, kawato developed the DB,
a humanoid robot that can imitate human action, based on his
knowledge that the cerebellum plays a key role in learning
and memory. however, the robot has managed to learn only
24 kinds of human action over three years.

---
atom
japanese researchers are advocating a grand project,
under which the government would spend 50 billion
yen a year over three decades to develop a humanoid
robot with the mental, physical and emotional capacity
of a 5-year-old human - the atom project.

'most of today's robots operate with a program written by
humans. in order to develop a robot that can think and
move like a 5-year-old, we have to first understand the
mechanism of how human brains work,' mitsuo kawato,
chief of the computational neuroscience laboratories
at the kyoto-based advanced telecommunications
research institute internationa said, admitting the difficulty
of his project. 'that will be equal to understanding
human beings.'

tthe project was inspired by the popular robot animation series
'tetsuwan atom' by the late cartoonist osamu tezuka
(unlike cartoonist tezuka's 'atom' character, known as
'astro boy' overseas, based on an image of a 9-year-old
boy, the atom project aims to create a humanoid robot
with the physical, intellectual and emotional capacity of
a 5-year-old that would be able to think and move on its
own). the researchers say it would help promote scientific
and technological advances in japan, just like the u.s.
apollo project, which not only succeeded in landing men
on the moon but contributed to a broad range of technological
breakthroughs - a project of this magnitude would inject
much-needed vigor into a nation depressed from years of
economic slump.

What is Advanced Robotics?

The term "advanced robotics" first can into use in the 1980s. It is used to define any sensor-based robots that attempt to mimic human intelligence. They are used in a variety of fields ranging from manufacturing, nuclear, construction, space and underwater exploration, and health care.

Popular culture is filled with advanced robotics. The robot on the television show Lost in Space and movie robots like Star Wars' C3PO and R2D2 were some of the first seemingly intelligent robots that average people were exposed to. In 1986, movie-going audiences met Johnny 5, the little autonomous robot from the movie Short Circuit. While all of these robots appeared truly autonomous, the robots themselves were largely a combination of puppetry and acting.

By the late 20th century, the science fiction of advanced robotics and the reality of it were beginning to overlap. Advanced robots of the 21st century are considered semi-autonomous. This mean that they are able to perform their tasks with a level of independence not found in automatic machines. Those called general purpose robots are able to perform their required tasks nearly independently. Some can recognize people or objects, talk, monitor environmental quality, pick up supplies and perform other useful tasks.

Robots are able to do these tasks through the use of a sensor. A simple example of this sensor is in room cleaning robots that bump a wall and understand to turn around and try another direction. Lawn mowing robots rely on underground markers to tell them this same information. Some of the most advanced robots are able to actually "see" through the use of infrared or stereo vision.

Some of the most advanced robotics of the 21st century are humanoid robots, meaning they resemble humans in their physical appearance as well as in their actions. They are considered autonomous because they can learn and adapt to changes within their environment. Johnny 5 is more of a reality in the 21st century than moviegoers of the 1980s could have imagined. Robots are being taught everything from how to load a dishwasher to mimicking facial expressions in response to particular types of human interactions.

One of the greatest feats of advanced robotics was seen in the rovers Opportunity and Spirit. Opportunity and Spirit landed on Mars in January of 2004 with the intention of completing an approximately 90-day mission. As of January 2009, five years later, they were still in operation. They landed on the surface with a precision unmatched in previous missions. They operate through communications with the National Aeronautics and Space Administration (NASA) and continue their missions through semi-autonomous interactions with the surface of Mars.

There were estimated to be about 3,540,000 service robots in use in 2006. At that time, there were an additional 950,000 industrial robots. In early 2009, Microsoft founder Bill Gates has predicted that every home will have a robot by 2025. Small robots like room sweepers and surprisingly complicated entertainer robots like Furby have been in homes since the 1990s. Given the advances even since those robots were introduced, the future of advanced robotics certainly seems boundless.

DC Motor-Driver H-Bridge Circuit

Description
Physical motion of some form helps differentiate a robot from a computer. It would be nice if a motor could be attached directly to a chip that controlled the movement. But, most chips can't pass enough current or voltage to spin a motor. Also, motors tend to be electrically noisy (spikes) and can slam power back into the control lines when the motor direction or speed is changed.

Specialized circuits (motor drivers) have been developed to supply motors with power and to isolate the other ICs from electrical problems. These circuits can be designed such that they can be completely separate boards, reusable from project to project.

A very popular circuit for driving DC motors (ordinary or gearhead) is called an H-bridge. It's called that because it looks like the capital letter 'H' on classic schematics. The great ability of an H-bridge circuit is that the motor can be driven forward or backward at any speed, optionally using a completely independent power source.

An H-bridge design can be really simple for prototyping or really extravagant for added protection and isolation. An H-bridge can be implemented with various kinds of components (common bipolar transistors, FET transistors, MOSFET transistors, power MOSFETs, or even chips).

The example provided on this page features:

* TTL/CMOS compatible Microchip or Maxim 4427A or 4424 MOSFET driver chips that protect the logic chips, isolate electrical noise, and prevent potential short-circuits inherently possible in a discrete H-bridge.
* Schottky diodes to protect against overvoltage or undervoltage from the motor.
* Capacitors to reduce electrical noise and provide spike power to the driver chips.
* Pull-up resistors that prevent unwanted motor movement while the microcontroller powers up or powers down.

A diode-less version of this circuit successfully drove Bugdozer (http://www.robotroom.com/BugdozerBrains.html#HBRIDGE) to mini-sumo victory. The more robust (diode protected) version actually illustrated above is from Sweet, the line-following robot (http://www.robotroom.com/Sweet.html).

R1 and R2:

Two pull-up resistors (any value from 10 kilohm to 100 kilohm).

These make sure the inputs are both on unless a signal from the microcontroller tells one or the other to turn off. With both on or both off, the motor doesn't spin because there's no voltage drop between them.

Think of these as default values. Unless a different value is specified, the lines are pulled up. This means the circuit can come loose or be disconnected completely and the motor won't spin or stutter.

Technically, R1 and R2 could be eliminated, although then the motors are likely to jerk when the microcontroller powers up or powers down.


IC1:

TC4424 dual MOSFET transistor driver chip. (The MAX4427 and TC4427A is the same but with a lower amperage rating.) The DIP part can be purchased at Digi-Key as part #TC4424CPA.

WARNING:

Direct motor driving with this chip is only possible for motors that draw less than 100 mA (4427) to 150 mA (4424) under load. To determine if your motors qualify, use a multimeter to measure how much current your motor uses under load (for example, when actually driving your robot around) when the motors are connected directly to the battery (not through these chips).

This chip is not really supposed to drive a motor by itself. If you find the chip gets very hot and the motor doesn't spin (or barely spins or stalls when loaded) then you need to have the chip drive some real power MOSFETs like it is supposed to. Check out Figure 10-13 and Figure 10-15 on pages 186 and 187 of Intermediate Robot Building. It's not that much more difficult and it really makes a huge difference in performance.

This chip provides two independent inputs that are compatible with CMOS or TTL chips. This circuit design uses IN A to vary power (on, off, or pulsed in-between) and IN B to determine direction.

OUT A follows the IN A signal but uses the full voltage from the power source, not the tiny voltage from the input signal itself. OUT B follows IN B in the same way.

For example, if IN A is turned on completely (2.4 volts or better) and IN B is turned off completely (0.8 volts or less) then OUT A turns on completely (up to 22 volts) and OUT B turns off completely (GND). The motor gets 22 volts.

This chip is constructed to protect the static sensitive MOSFETs, but also to protect the input sources from current being jammed back by the motors. Optoisolator ICs could be used at the inputs if greater protection and freedom from noise is desired.

Normally four transistors are needed in an H-bridge. Each transistor forms a corner in the letter 'H', with the motor being the bar in the middle. (See Figure 9-14 on page 158 of Intermediate Robot Building.) In this design, each output of the chip forms a complete vertical side of the letter 'H', with the motor still being in the middle. Because a side is now a single output, short-circuits can't form from the top of a side to the bottom of a side. No matter what the inputs, all power must travel from one side to the other -- through the motor.

A mechanical switch, relay, or logical gate could be used to turn the inputs on and off. It would work just fine at providing no movement (on/on or off/off), forward movement (on/off), or reverse movement (off/on). To provide power levels in between (like 50%), rapid pulses of on or off can be provided by pulse-width modulation using a chip or timer.

An important note regarding current rating: The plastic DIP package can only dissipate enough heat when the power usage is below 730 milliwatts. Therefore, it isn't possible to continuously run the chip at both the maximum voltage (22 V) and maximum amperage (3 A) rating. That would result in 66 watts of power usage. (That's 100x the maximum allowed.)


From: Paul Jurczak
Sent: Monday, March 12, 2001 10:59 AM
Subject: DC Motor-Driver H-Bridge Circuit

The actual DC power losses in the H-bridge would be:
I2 * (Rl + Rh)
= (3 A * 3 A) * (2.8 ohm + 2.5 ohm) = 47.7 W typical
and
= (3 A * 3 A) * (5 ohm + 5 ohm) = 90 W maximum

Which still is more than enough to melt this IC.

Paul.


I'm sincerely grateful for the feedback.

Paul is correctly pointing out that the chip only needs to dissipate the portion of power used in the chip's resistance.

For current to flow, the chip must have one gate high and one gate low. Therefore, Paul is adding the typical high and low resistance (from the 4427 datasheets) together to calculate the total amount of resistance the chip causes.

When a moving motor is added to the circuit, the motor uses up some (hopefully most) of the power. Just dive for that robot if the motors stall!

In summary, the chip can't run at maximum volts and maximum amps because most of the 66 watts (47 watts typical) would need to be dissipated by the chip.

Thanks Paul!


D1 and D3:

Schottky small-signal diodes.

I couldn't find any! So, I used 5817 Schottky diodes instead.

The key factors in substitution are:

* Are the diodes rated to turn on with less voltage than the TC4424's internal transistor base voltage? (600 millivolts)
* Are the diodes rated to handle the maximum reverse voltage? (22 volts)
* Are the diodes rated to handle the maximum current? (3 amps)

In the case of the 5817s, the datasheets answers are:

* Yes. (400 millivolts or less)
* Nearly. (20 volts -- so this is the circuit's new voltage maximum)
* Yes, peak (25 amps)

When a motor accelerates or decelerates for any reason (signal, load, or friction), there is reluctance for the electric field present in the motor coils to change. More properly, the changing field induces power. This "refunded" power can jam back into the chips.

D1 and D3 protect the chips from overvoltage by turning on when more voltage is coming from the motor than is coming from the batteries. The batteries absorb the power.

The turn-on rating of the diode must be lower than the turn-on rating of the chip, or else the diode won't turn on early enough to protect the chip.

Because the diode is installed in "reverse", the power can't flow from the batteries to the motors. If the diode was installed differently, power would immediately flow to the motors, bypassing the chip outputs (or worse, short-circuiting through the chip).

By the way, this arrangement is why the reverse or breakdown voltage of the diodes is important. If the reverse voltage rating was less than the full battery voltage, the battery would break down the reversed diode and just shoot through.


D2 and D4:

Schottky small-signal diodes.

D2 and D4 protect the chips from undervoltage (less than ground) by turning on when the voltage in the motor is below GND. Once again, the batteries take care of the problem, rather than power flowing backwards from the chip.

D1 through D4 could be eliminated. In fact, Bugdozer runs without the diodes. However, parasitic voltages can and do temporarily short power supplies (reset!) and can even destroy the driver chips.
Despite what may seem complicated at first, the above photograph includes added features such as an LP2954 5V voltage regulator, a bicolor LED, and two switches for testing.

One H-bridge drives one motor. For a common two-wheeled robot, obviously two copies of the H-bridge circuit are needed.

* Pressing the right-side button makes the motor turn counter-clockwise and lights the LED green.
* Pressing the left-side button makes the motor turn clockwise and lights the LED red.
* Pressing both the buttons turns on the brakes (stopping the motor) and turns off the LED.
* Pressing the brakes quickly enough provides variable speed (between 0% and 100%).