As the name indicates, SLIM-BOT, is a small, simple, compact robot, which may be moved or controlled using various inputs, without using any micro-controller. There is no need of programming language or coding to make and control the Slim-Bot. This is the basic project for those, who don’t have any knowledge in micro-controllers and programming. The various controls for the Slim-Bot is completely based on the electronic circuits only.
Now, the Slim-Bot may be controlled wirelessly, using simple and easy control with 5D (Five Degrees of Freedom) Rocker Joystick. A 5D Rocker Joystick module has a small knob to control in all the five directions (Up-Down-Right-Left-Mid) along with two button switches (Set and Reset), which is easier for manoeuvering the Slim-Bot than Analog Joystick. All the outputs of 5D Rocker Joystick are digital. So, the control circuit becomes simpler compared to analog Joystick. So, the digital values are directly fed to Encoder IC (HT12E) and then transmitted wirelessly using RF transmitter.
The serial data is received by the RF receiver, which sends it, to Decoder IC (HT12D). The Decoder IC, decodes the received serial data, back in to 4 bit data. The 4 bit data is used to control the movement of the Slim-Bot.
About 5D Rocker Transmitter:
The 5D Rocker Joystick module used here is easily available in the market, which has a berg strip as connecting pins. The 5D Rocker Joystick module contains a common input pin (COM), with seven digital output pins, viz., Up, Down, Left, Right, Middle, Set and Reset.
When the knob is moved horizontally (left or right), the button switches on left or right side of the knob gets connected to COM pin, and pins LFT or RHT are connected to COM pin. Similarly, when the knob is moved vertically (up or down), the pins UP or DWN are connected to COM pin. In case the knob is pressed down or set or reset button is pressed down, then the COM pin is connected to MID or SET or RST pins respectively.
So, when the COM pin of 5D Rocker Joystick module is connected to DC power supply (or match to circuit power supply voltage), and turning the knob or pressing each button switch (using rocker knob), the voltage appears at one of the pins UP, DWN, LFT, RHT, MID, SET and RST accordingly. It means the particular pin goes logic HIGH with corresponding operation of the knob or pressing the specific button switch.
Here, the UP, DWN, LFT and RHT pins are connected to the Encoder IC (HT12E), with two diodes as explained in the Wireless Keypad Control. Then the digital code is encoded by the Encoder IC (HT12E), which outputs the code in serial format. Then the serial output of the encoder is transmitted by an RF transmitter. The connections between 5D Rocker Joystick to Encoder IC (HT12E), then to the RF transmitter module, are shown in the circuit diagram below.
About Receiver Board:
There is NO CHANGE in Receiver Board or Slim-Bot, w.r.t. Keypad Control system. Once the Transmitter module is ready, then switch ON the power supply to Transmitter and Slim-Bot for easy control of Slim-Bot using 5D Rocker Joystick.
The Receiver circuit diagram is shown below.