Wednesday, September 26, 2007


Intelligence is a property of system or an entity that encompasses many related abilities, such as the capacities to reason, plan, solve problems, think abstractly, comprehend ideas and language, and learn.

Lets see what kind of intelligence do humans have(ideally!! :)

1. Naturalist Intelligence (“Nature Smart”)

Designates the human ability to discriminate among living things (plants, animals) as well as sensitivity to other features of the natural world (clouds, rock configurations). This ability was clearly of value in our evolutionary past as hunters, gatherers, and farmers; it continues to be central in such roles as botanist or chef. It is also speculated that much of our consumer society exploits the naturalist intelligences, which can be mobilized in the discrimination among cars, sneakers, kinds of makeup, and the like.

2. Musical Intelligence (“Musical Smart”)

Musical intelligence is the capacity to discern pitch, rhythm, timbre, and tone. This intelligence enables us to recognize, create, reproduce, and reflect on music, as demonstrated by composers, conductors, musicians, vocalist, and sensitive listeners. Interestingly, there is often an affective connection between music and the emotions; and mathematical and musical intelligences may share common thinking processes. Young adults with this kind of intelligence are usually singing or drumming to themselves. They are usually quite aware of sounds others may miss.

3. Logical-Mathematical Intelligence ("Number/Reasoning Smart")

Logical-mathematical intelligence is the ability to calculate, quantify, consider propositions and hypotheses, and carry out complete mathematical operations. It enables us to perceive relationships and connections and to use abstract, symbolic thought; sequential reasoning skills; and inductive and deductive thinking patterns. Logical intelligence is usually well developed in mathematicians, scientists, and detectives. Young adults with lots of logical intelligence are interested in patterns, categories, and relationships. They are drawn to arithmetic problems, strategy games and experiments.

4. Existential Intelligence

Sensitivity and capacity to tackle deep questions about human existence, such as the meaning of life, why do we die, and how did we get here.

5. Interpersonal Intelligence ("People Smart”)

Interpersonal intelligence is the ability to understand and interact effectively with others. It involves effective verbal and nonverbal communication, the ability to note distinctions among others, sensitivity to the moods and temperaments of others, and the ability to entertain multiple perspectives. Teachers, social workers, actors, and politicians all exhibit interpersonal intelligence. Young adults with this kind of intelligence are leaders among their peers, are good at communicating, and seem to understand others’ feelings and motives.

6. Bodily-Kinesthetic Intelligence (“Body Smart”)

Bodily kinesthetic intelligence is the capacity to manipulate objects and use a variety of physical skills. This intelligence also involves a sense of timing and the perfection of skills through mind–body union. Athletes, dancers, surgeons, and craftspeople exhibit well-developed bodily kinesthetic intelligence.

7. Linguistic Intelligence ("Word Smart")

Linguistic intelligence is the ability to think in words and to use language to express and appreciate complex meanings. Linguistic intelligence allows us to understand the order and meaning of words and to apply meta-linguistic skills to reflect on our use of language. Linguistic intelligence is the most widely shared human competence and is evident in poets, novelists, journalists, and effective public speakers. Young adults with this kind of intelligence enjoy writing, reading, telling stories or doing crossword puzzles.

8. Intra-personal Intelligence ("Self Smart”)

Intra-personal intelligence is the capacity to understand oneself and one’s thoughts and feelings, and to use such knowledge in planning and directioning one’s life. Intra-personal intelligence involves not only an appreciation of the self, but also of the human condition. It is evident in psychologist, spiritual leaders, and philosophers. These young adults may be shy. They are very aware of their own feelings and are self-motivated.

9. Spatial Intelligence (“Picture Smart”)

Spatial intelligence is the ability to think in three dimensions. Core capacities include mental imagery, spatial reasoning, image manipulation, graphic and artistic skills, and an active imagination. Sailors, pilots, sculptors, painters, and architects all exhibit spatial intelligence. Young adults with this kind of intelligence may be fascinated with mazes or jigsaw puzzles, or spend free time drawing or daydreaming.

Question: Can machines have such intelligence ?
Answer: Yes and No

Machines can now have most of these types of intelligence barring a few. They may not be as good as those visualized by many famous Sci-Fi authors like Isaac Asimov, Douglas Adams, George Lucas, but are quite close.
With this we begin a series of tutorials giving brief idea of what kind of intlligence can machines have and how .

Tuesday, September 25, 2007

Diameter of the wheels, speed and torque:

With the motor giving constant RPM the wheel diameter is the last criterion to maintain torque- speed balance.
Let V be the linear speed, T be the torque given by the motor,
w be the angular velocity
Let Tf be the torque developed by the ground as reaction to the wheel's movement.
This is the torque resisting the robot's movement.

For the robot to move from rest (or to accelerate), T must be bigger than Tf.

The toque Tf = F.r .......(1)

Also note the that the linear velocity of the robot equals the linear velocity of any given point on the outer circumference of the wheel,

Then the velocity V = w.r .......(2)

From the relations (1) and (2) :
Increasing the radius of the wheel will increase the velocity of the robot, but also increase the resisting torque that the robot have to overcome. Thus, varying the radius of the wheel, you can make a compromise between linear velocity and torque of the robot.

Friday, September 21, 2007

Traction and steering mechanisms for a car type robot

Note: Here in this tutorial aspects like aerodynamics and vibration damping are not taken in account.

There are many kinds of techniques to move a robot from one place to other. But here I will discuss only some few techniques adequate for relatively smaller robots driven by dc motors.

1.Differential Drive system:
This is the simplest and the most common type of mechanism used in small robots.
It's easy to build, easy to control and can permit the robot to move in all required directions.
Two motors are connected, one to each of the two drive wheels at the right and at the left of the robot's base. Those two motors are responsible of driving the robot forward and reverse.

The turning of the robot relys on the velocity difference of the motors. Thats why it is called a 'differential'.
Figure on the right shows operation principle.
When the left and right motors are turning at the same speed, the robot moves forward or backward in a straight line.
In order to turn right, the right motor is slowed down and the robot steers to the right. The bigger the difference of speed between the two wheels, the tighter will be the steering curve.

2.Four wheel differential drive system

The drive trains of tanks and bulldozers is similar to this one.
It requires relatively powerful motors, because during turning there is a lot of friction.

Similar kind of a differential mechanism is used as above.

The advantage of this system is that it is very easy to build and is most suitable for running on low friction and dusty surfaces where other drive systems are not effective.

3.Car-type drive system:

I think that the image is clear enough to understand this mechanism.

4. Divided chassis drive train:

This system relies on 4 independent motors, each one coupled to one of the four wheels, allowing the robot to move forward or backward with the
accumulated power of four motors or to turn right and left with approximately equivalent power, but with m minimum frictional losses.

he chassis is divided into two parts, hinged together, allowing it to change it's shape to turn in tight curves.

Usually, the two front motors are used only to drag the robot, while
the two rear motors are used either to push it or to bend the chassis (like a toy train) to turn right or left by running one of the two motors faster than the other.


Sunday, September 9, 2007

Kinematics of a Robotic Arm

I dropped the idea of designing a robotic arm initially due to the kinetics.. :P
I found the reverse kinetics tough enough that I surrendered and dropped the very idea of a robotic arm.
Still I do feel I will start working on this project some day (in my undergraduate only)

Robot Kinematics is the study of the motion of robots. In a kinematic analysis the position, velocity and acceleration of all the links are calculated without considering the forces that cause this motion.

Robot kinematics are mainly of the following two types: forward(or direct) and inverse kinematics.

Forward Kinematics (angles to position)
What you are given: 1.The length of each link
2.The angle of each joint

What you can find: The position of any point
(i.e. it’s (x, y, z) coordinates

Serial chains:

The solution is always unique: one given joint position vector always corresponds to only one single end effector pose. The FK problem is not difficult to solve, even for a completely arbitrary kinematic structure.

Methods for a forward kinematic analysis:

  • using straightforward geometry
  • using transformation matrices

Parallel chains (Stewart Gough Manipulators):

The solution is not unique: one set of joint coordinates has more different endeffector poses. In case of a Stewart Platform there are 40 poses possible which can be real for some design examples. Computation is intensive but solved in closed form with the help of algebraic geometry.

Inverse Kinematics (position to angles)
What you are given: 1.The length of each link
2.The position of some point on the robot

What you can find: The angles of each joint needed to obtain
that position

In contrast to the forward problem, the solution of the inverse problem is not always unique: the same end effector pose can be reached in several configurations, corresponding to distinct joint position vectors. A 6R manipulator (a serial chain with six revolute joints) with a completely general geometric structure has sixteen different inverse kinematics solutions, found as the solutions of a sixteenth order polynomial.

(Detailed tutorial for analysis and solving to come later)

Monday, August 20, 2007


Today i was searching for some tutorial for EFFECTIVE soldering...

I came across a very good tutorial..

ALL THE BASICS explained....efficiently....

HAVE A LOOK.....nd plz post ur comments...