How to build a 6 legged Robot

Spyder Hexapod 


 1. Structure

 2. Servo Motor

 3. Robot walking algorithm

   4. Servo Motor Control

 5.  Tools Used

 6.  Video

Structure of the Robot:

The structure involves a Aluminium base to fix the 3 servo motors. It is made of a rectangular base ,built using Aluminium  frames used in making windows.

 The mountings of the 3 servos  in the aluminium frame is as  shown:

Fig 1: Orthogonal View

Fig 2 : Side View

Fig 3 : Top View

Fig 4 : Completed Robot with legs attached

Servo Motor

The Hexapod has 6 legs, and requires 3 servos to operate them. I have used Tower Hobbies TS-53.

    To know what is a servo and how it works check the Seattle robotics Servo Page for more details.

Robot's Walking Algorithm

The robot uses tripod walking gait.

At any point in time the Hexapod has 3 legs on the ground. The center legs are used to lift the hexapod up while the front and back legs does the job of giving the robot forward or backward thrust.

Check this link below to understand the walking dynamics of Spyder.

Link : 6 legged robot walking simulator

Servo Motor Control

Servo Motor position is controlled using a PWM waveform. Changing the ON time of the PWM waveform results in change of the Servo Position.

   For digital control of the PWM waveform we should have the PWM generation algorithm to be programmed into a microcontroller. This Microcontroller (uC) can be programmed to recieve commands ( Servo position commands ) via the serial port and then based on the command provided the uC generates the respective waveform which  make the Servo move to the position as instructed by the command.

Tools Used

Microcontroller used:Atmel 89S52

Programmer used:Asim Khans Atmel Programmer

Programming Language : C

NOTE: For getting the hex code to program the 89S52 controller, you can mail me at the address give below.

Video Link

Counter:free tracking

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