Chassis according to Wikipedia is a chassis consists of a framework that supports an inanimate object, analogous to an animal's skeleton, for example in a motor vehicle or a firearm. According to me it is the skeleton of the robot. The first part of a robot is its chassis. The shape and size of the chassis depends upon the shape of the robot or vehicle to be made. The shape can be circular,rectangular,triangular. Circular and rectangular shapes are most widely used but you can make chassis of any desired shape,it can even be irregular depending upon the application of the robot.
Now it is important to select the material of the chassis. The selection criteria depends upon following factors:
(1) The size of the robot
(2) Budget
The larger the size of the robot the larger the weight bearing power is needed therefore for small robots wood or plastic materials are used for making the chassis.
For larger robots cast iron is used because it is cheaper and weldable(Can be easily welded other metal parts) but only problem is that it gets corroded easily,therefore it is usually painted on all sides. Another option for heavy robots is use Galvanized Iron sheets it is rust free but doesn’t weld. For light weight robots aluminum or brass sheets are used.
Selection of chassis is very important task because it acts as a housing for all other parts such as batteries,motors,sensors,wires and also gives the robot a specific shape.
What is a line follower?
A line follower is an autonomous vehicle which follows a line path(straight or curved) that maybe of any colour.
what this statement means is that the line follower will move on its own by following the line.
I have always been fascinated by autonomous vehicles like micromouse, line follower the best thing about them is that they move without any external control.
So a line follower has the following requirements:
1. It requires a Sensory Device which would help detect the line.
2. It requires a Brain to control its motion helping to follow the line.
3. It requires Locomotion which would help it ro move along the line.
4. It requires a Mechanical Structure which would support all these devices.
SENSORY DEVICE:
The most important part of the line follower is its sensory part which detects the line.
It senses the line and produces an output in the form of potential drop.
For example, an LDR(Light Dependant Resistor) has different resistances for different intensities of light,low resistance for higher intensity and vice versa.
An IR sensor is also a good option as a sensory device it also produces a potential drop across it.
for more info on IR sensor:Link to IR Sensors
or u can also use an LED
For details for how to use LED as a sensor visit this site.
Though it is important to note that more the number of sensors employed the better the line follower becomes.But programming becomes more and more complex with increasing number of sensors
U can also use a web camera to detect the line and follow it using image processing for interpretation.
But it would increase the cost of the line follower by two folds.
BRAIN:
Now the signal produced by the sensors of the line follower is to be interpreted by a logic circuit.
This logic circuit can be purely electronic(if u are good at hardware) or using Microcontrollers like AVR or 8051 which u can program using C. Through a suitable program u can control the motion of the line follower. Suppose if u get a signal logic 1 as an input and if you're following a black line then u would move right or left accordingly.
for example if u have two sensors on both sides of the line and if detect logic 1 one and logic 0 on the other sensor(then u have moved on the left of the line) so to counter u will have to move to the right side.
This way u will follow the line.
Locomotion:
Now for locomotion of the line follower we require motors.We require lightweight motors which can have low torque and medium(now for controlling high rpm motors we require an H-bridge see article for fast change of change of direction)
The motors should be d.c. motors(it is preferable not use stepper motors instead use differential mechanism for the line follower).
Mechanical Structure:
We should use a lightweight chassis as the torque of the motors is low and so they cannot support large amount of weight. The chassis can be made of lightweight plastic or wood.
And we also need a large amounts of nuts,bolts and screws to fix the motors and the electronic parts of the line follower.
Watch this great video:
It is the video of a very fast Line follower and completes three laps in very less time.
It inspires a lot.
The name of the line follower is Jet.
Earlier i had posted a video of obtaining a magnet from an old hard drive.
Link to the older post: 5 minute projects from Popsci
So i had a old damaged hard drive so i gave it a try:
This how my hard drive looks from outside
The problem was that i had a screw driver but the screws on the hard disk were hexagonal in shape
So i had to buy a TORX SET costing about 150-200 Rs
I unscrewed all the screws the result was i could see the inside of the hard disk
and ......
in the end i managed to remove a magnet for putting stuff on my fridge from the hard disk
Who might have thought so much innovation can be done on a simple nail then see this article on
Hurriquake Nail which is develop to resist natural disasters.
See this article:
Hurricane winds rip apart nailed-together walls, and earthquakes shake houses so violently that a nailhead can pull straight through a piece of plywood. Since we can’t stop natural disasters, Bostitch engineer Ed Sutt has dedicated his career to designing a better nail. The result is the HurriQuake, and it has the perfect combination of features to withstand nature’s darker moods. The bottom section is circled with angled barbs that resist pulling out in wind gusts up to 170 mph. This “ring shank” stops halfway up to leave the middle of the nail, which endures the most punishment during an earthquake, at its maximum thickness and strength. The blade-like facets of the nail’s twisted top—the spiral shank—keep planks from wobbling, which weakens a joint. And the HurriQuake’s head is 25 percent larger than average to better resist counter-sinking and pulling through. The best part: It costs only about $15 more to build a house using HurriQuakes. $45 per 4,000;