View Full Version : help with an effective communication system for our hexapod.

06-13-2005, 02:50 AM
we are a team at delhi college of engineering and we have been building a hexapod with a 8052 as the logic controller. we are presently looking to integrate various sensors into this hexapod like ir sensors, whiskers, and within a month a comprehensive vision system. i would like to ask if anybody can tell me how to go about building a complete communication system for this robot so that it can interact witha laptop in a 50 metre radius, relaying vision,and major parameters to this laptop so that it is not only autonomous but can also be manually controlled if an emergency arises..............
and in this group i have the task of finding out the sensors interfacing with the microcontroller. can anybody please advise where to start??

06-14-2005, 12:46 AM

We actually did this for our final year project. You can check our hexapod at


We use RF modules for communicating with the master PC. It works great. We've IR ranger, touch switches and tilt sensor on the robot but no vision system. I think the hardest part 'll be the vision part. Anyway good luck for your work !!



06-15-2005, 03:04 AM
hey thats an excellent piece of work u got there. can u answer a few questions i have got...........

how on earth did u design the hexapod mechanically?
what designing software have u used?if any
how did u fashion the links and legs so well?
we did it in our dce workshops ourselves and ours doesnt look anywhere like urs does.
where did u get the servos from??
we are using futaba servos.

MOST IMP......can u pleeeaase tell me how did u design the controlling software on the pc??did you use visual basic or something similar??any place i could get some example codes using vb to control a robot on a remote comp??

ps.....fantastic work.

06-16-2005, 12:31 AM

Thanks for ur comments !! :-) A few answers here


Search for this document Design and Implementation of a Multilegged Walking Robot by Willard S MacDonald. It's a good start.

We used the following softwares
CAD - AutoCAD 2002
Mechanism Simulation - SAM 5.0 from Artas Engineering Software www.artas.nl

About the links and legs, you can do it easily using some CAD packages. We actually spent a lot of time on it !!

Most of the parts are cut in a fabrication workshop. We gave the engineering drawings. Finally we used lapping and polishing compound for finishing the parts.

We ordered the servos from www.towerhobbies.com, USA. We use hitec servos. Futaba servos are also good.

Computer interface is done using VB 6.0. To control a robot using VB, everything you need to know is, how to use MSComm control. If possible get a copy of Serial Port Complete by Jan Axelson available from http://www.penram.com/ It's a good book on serial port and RS232 communication.

You can see some images of computer interface here


Do ask me if you've more qns.



06-16-2005, 12:36 AM

What material u use for the robot, Aluminium or Acrylic? What's the DOF per leg 2 or 3? Just to know, if you don't mind. Good luck for your work.



06-16-2005, 03:06 AM
hey thanks again.
our hexapod has 2 DOFs per leg and we have used aluminium both for the legs and the base.
we have done the designing on autodesk inventor 9.
we are currently in the procedure of completing the finishing parts of the pod without the vision system. as soon as we are done i will send u some pics and videos.
it seems u are a hardcore robotics person. well atleast we share the same level of enthu is all i can say at the moment.
which college are u from.... gathering that u have given the final semester.
ps>>how did u write the codes for the pics u have used . i mean in c or in assembly??
i know 8051 assembly well. is pic similar??
thanks again.

06-17-2005, 11:44 PM

I'd love to see the pics and videos !!

I used CCS C cross compiler for programming the PIC. Sorry I'm not so familier with asm. I think ice can give some comments on this :-), he's a expert of PIC asm.


I'm from Mar Athanasius College of Engg. Kerala. I just finished my course in ME.

Pls do update us with your progress. Good Luck.



06-18-2005, 11:10 AM
now we got 3 walkers on RI..hehe

the difference between a PIC and 8051 is thir architecture
8051 is CISC [complex instrution set]

whereas a
PIC is RISC [Instruction set]

This means that a PIC has only 35 instructions as opposed to 8051's numerous instructions.

You do get C compilers for both..
I do PIC using PICbasic ,CCS compiler and sometimes assembly..]

06-18-2005, 04:07 PM
it feels encouraging to see some stalwarts taking interest in our humble project....i have a rather complete knowledge of 8051 asm... but we want to add another uC to our knowledge database... will come in handy.... so what do u suggest that we learn the pic programming in c or in assembly? can u recommend a book pic programming in c??


06-19-2005, 11:46 AM

Hey, happy_99 and ice, which version of CCS PIC are you people using? I found that ver3.200 full of bugs, what do you say…


06-20-2005, 12:12 AM
so what do u suggest that we learn the pic programming in c or in assembly?

C => Fast coding but large size
ASM => Tough coding but tight code

So the best method is to use ASM for time critical routines and C for others. What I'd like to say is learn both ASM and C.

Jack pls chk ur PM



06-20-2005, 02:59 AM
thanks... we have already started with pic asm and are halfway through the book . it will be completed at the end of this week.
will keep u posted about our hexapod progress .

06-20-2005, 07:09 PM

My Quadraped is complete too..

I will be pretty soon uploading images and videos on the net...

Those who catch me online on yahoo can ask for live webcam demo...

My yahoo ID = shant_p