GAMEPLAN

STAGE 1:FILL THE BUNKERS: A Test of Speed

STAGE 2:ROBO COMBAT: A Show of Power

FOR MORE DETAILS VISIT THE TRYST WEBSITE….!!

what you need to know . . .

The first robot is always the hardest.

So we will take the KISS approach:

Keep It Simple, Stupid!

your first robot will have 2 wheels

driven under the most basic algorithm – Differential Drive.

• to drive straight both wheels move

forward at same speed

• to drive reverse both wheels move

back at same speed

• to turn left the left wheel moves in reverse and the right wheel moves

forward

• to turn right the right wheel moves in reverse and the left wheel moves

forward

Wheels and Motors

• Big wheels will let your robot move faster. Small wheels for slower.

• But bigger wheels means your robot has less torque to carry a heavy payload

• Choosing motors would involve calculations of weight, gearing ratios, desired terrain, desired velocity and acceleration, voltage, power consumption, controllability and a whole range of things too overwhelming for a beginner

Arey IIT JEE ke funde lagaayo yaar!!

Types of motors to use

• DC geared motors

• Drive trains

Set of gears arranged in a pattern

Motor on which a gear box is mounted.

Voltage: 6V - 24V Torque: double what you think you will need

Specific components you may need

– Voltage Regulator

– L293D - Motor driver + H bridge

• Drive a pair of DC motors/Geared Motors

• Motor supply voltage can go up to 24Volts

• Maximum of only 600mA current/channel

• Enough to drive small DC geared motors

Remember to add 0.22uF capacitors across both the motors to reduce the effect of noise on the circuitry

What about higher current requirement ?

• Use ULN2003 – current amplifier

• …and relays for switching

(as explained earlier)

Use protection diode for relays

Wired / Wireless Remote control

• Wireless remote control complexes the circuitry

• But you can get rid of that long wired tail dangling out of your remote control robot

• Easiest solution would be to hack those cheap wireless toy cars, take their electronic guts out and use them in your robot

• For more flexibility, you can build a custom remote control system

Use RF Tx/Rx modules and encoder/decoder ICs

Tools and some other components

Wire Stripper Pliers Variable resistors Switches

Diodes Transistor

Capacitor

Battery clips

Solder sucker Soldering iron with stand

Circuit board

Always follow the principle ‘ DESIGN,THEN BUILD ’

planning things is generally always a good idea

“for every hour spent on design is one less hour spent on construction” (and usually low quality construction at that!)

Mechanical Aspects

• Make sure that the machine is properly balanced.

• Bring the machine’s CG as low as possible.

• Achieve this by bringing the motors as close as possible to the ground.

• Make the weight of the front and rear of the machine nearly equal to prevent toppling.

• Check your motors for enough torque.

• Try to reduce total machine’s weight by using lighter materials and as less material as possible.

Frame

• basic structure to which you attach everything else.

• probably the largest part of your robot.

• make sure it is made of a light weight rigid material such as aluminum.

Advantages

• Reasonably cheap

• Easy to work on

• Strong enoughWheel Basics

• Wheel diameter ( discussed earlier )

• Wheel texture : smooth wheel will not have much friction

skid while accelerating and braking

really rough wheel, has higher friction with the ground

consider wear and tear

• Wheel width : increased resistance to rotating the wheel on a surface

• Wheel centre hole diameter : depends on length and diameter of your motor output shaft

Gripper design – mechanisms

• Material used : Aluminum

• Use 2 motors, one each for the hands of gripper.

• Use single motor mounted on one hand and other coupled to it using gears.

• gripper should be light weight : use light weight motors

• use foam or rubber to increase friction

• Design the grip acc. to the object.

For picking up the ball use cup shaped grip.

Tools and some other components

Places to acquire materials

Everest Lajpat Rai Shop no. 629Motors, Solenoids, Light sensors, Encoder disks23869522

Mehta BrothersLajpat Rai Shop No. 614ICs,SMD components,LCD,Wireless Radio modules, Connecters computer type,23869876

MehtaShop No. 463 Lajpat RaiBattery,ICs23868294

Prakash Radio1675 Bhagirath PalaceRelays + connecters, switches,push buttons

R Kumar Shop no. 3602 , Ph. 23912860 Mechanical components

‘difficult to describe but you will know one if you see one’

To catch up the demonstration of some of our BOTS, you all are welcomed to assemble in Robotics room, SAC at 8 pm, today…