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i went through the construction details of ur robo project taurus 2...there are some things i wud like to discuss...
i got a video in which the testing of the circuit is done..there i saw tht the wheels apart from rolling are also rotating bout the vertical axis...
so i was just wondering wat can made to do tht...i mean there has to be some constraints between all the 4 wheels so tht they take the robot in the single direction...but as all the four wheels were powered with different servos and they have their individual axis....wat can make them move so smoothly???
I am sorry if my question seems too dumb to you people...

and one more thing i want to ask is tht which code designer software and compiler and uploades i shud use in the strt...and which language i need to know for programming a bit tricky robots....

sorry for such lame questions but i wud be thankful if somebody cn help...its my strt to this field!!!

I figure for the wheels to turn vertically admin used 180 degree servos due to the fact that they have feedback control, he then used that feedback to control the direction of each wheel and tell the horizontal servos which direction to go as to not go against the rest of the bot.

Vertical= 180 degrees w/ feedback
horizontal= 360 degree servos

Also servos are pretty precise so i cant imagine that being to hard

(2) 7.2V nicad battery packs ($16)
(1) CMUcam ($100)
(1) Cerebellum Microcontroller, by Botrics ($40)
(3) homemade IR (~$4 in components)
(8 ) HS-311 servos ($71)
(1) null modem cable ($3)
(4) foam 4 inch diameter model aircraft wheels ($15)
(1) 1'x1' sheet of HDPE ($10)
(2) ball bearings (found in a scrap pile)
(1) 1'x1' sheet of aluminum ($10)

is the parts list, so im geussing that admin didnt expect for there to be high enough friction to offset a wheel

just to add on to gamefreak's comment . . .

the robot actually wasnt that hard to build - i only started making robots two years earlier than when I made T2. for the smooth line following operation I used a very simple fuzzy logic algorithm with a tweaked constant. i just needed to do that calculation for the left and right front wheels, then invert the angle for the rear wheels.

other motions, such as 360 degree turning and sideways straffing, i just hardcoded servo angles.

for the sinusoidal motion, i had the servo angles add +1 at each computational cycle until the angle maxed out, then had it subtract -1 at each computational cycle. i couldnt actually calculate sin(angle) because the PIC16F877 takes forever to do a single trig calculation (1/4th a second I think).

hey admin, what would you have done if something would of jammed the wheel from turning around the vertical axis.

You would have 1 wheel that wouldnt be hardcoded unless yo forced the servo back :D

Another reason I like mechanical simplicity.


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