As you know, we will Create a simple robot that will go toward the light and stop if there is no light. This BEAM robot is very simple even a someone without knowledge of the BEAM robots can make it. Scheme to make the robot is described in many sites, but none of them are not written as an absolutely necessary to connect all the cables, circuits, motors and much more. Because not everyone when viewing the scheme, they will understand. So here will be also shown in the pictures.
In this article I do not open anything new, I just took the robot scheme, as described on many sites but all the actions I take pictures.
So … our job is to make BEAM-robot. What do we need?
- L293D (engine driver)
- Resistor 100 ohms not less (I used 180 ohms)
These are the basic details that we need. But we also need a robot chassis, power supply, motor and wheels.
I did not want to reinvent the wheel, and therefore took the body from old toys, two electric motors and 203:1 tracked chassis. And this is the design.
But I do not think you have the same toy. Therefore, an alternative would be a case of … wood. Yes – made of wood. Do not worry. Of course, you can do and made of plastic, but not everyone has it. But the tree can be found everywhere.
Housing our BEAM robot will consist of a rectangle with sides of 100 mm by 60 mm (width may be greater if you use large electric motors).
Well … you have made the case and now you can start soldering.
I’m not going to talk about all sorts of options L293D: this you can read on other sites. I’ll show you the photos, which you clearly see what and where to connect.
Now take five wires, and connect them like this.
Now we connect to this construction, the resistor and phototransistor. It is very important to solder the resistor on the phototransistor shorter legs, and solder the blue wire to the other one.
Now we’ll all be connected to the motor driver.
For a start – four wires to ENABLE1 and Vss, Vs and ENABLE2.
Now connecting to the phototransistors INPUT 1 and INPUT4.
And now we join the resulting design with two engines.
In the figure: the upper motor and solder to OUTPUT1 OUTPUT2, and the lower to OUTPUT4 and OUTPUT3.
That’s almost all: you only connect it all with the power supply. I used three AA batteries at 1.5 V.
First connect the negative (black wire that is connected to two blue – GND and GND, GND and GND)
Well, the red wire (positive) – the holder of the batteries by the end of the left resistor.
As you can see, I soldered the red wire not directly to the resistor, but through the switch.
Here we are with you and have a simple BEAM robot that reacts to light rays.