ROBOTC.net Blog  

ROBOTC News

Bridge laying, the NXT method

No comments

Miniaturized SPRAT model controlled by 3 NXT bricks using ROBOTC.

ROBOTC community member Didier Coll has created more than a few awesome robots. In the past couple of months, though, he has made some truly spectacular bridge-laying robots using ROBOTC over multiple NXT bricks.

The first creation is an AMX-13 type bot, which (unlike the other two robots) carries the bridge on its front. Like the MLC-80 though (below), the AMX-13 is programmed to place the bridge and then drive across: it uses 2 motors and 8 actuators controlled via 2 ROBOTC-coded NXT bricks to achieve this goal.

The second robot is based off of the French Army’s current EFA design. Much like a real EFA, the robot drives to the middle of the ‘river’ and extends the folded bridge sections using a series of LEGO pistons; the robot stays in the middle of the bridge and the other robots effectively drive over it. The EFA model uses 2 NXT’s, 3 Multiplexors, 4 motors, and a staggering 10 actuators to perform this task.

Didier’s final robot is a replica of the SPRAT MLC-80 used during WWII. It uses 3 NXT bricks, a whopping 9 motors, 9 actuators, and 5 servos to place the bridge and drive across it, all controlled by ROBOTC for MINDSTORMS. A sample of the ROBOTC code used for this robot is below.

#pragma config(Sensor, S1,     HTIRL,          sensorI2CCustom)
#pragma config(Sensor, S2,     PSPNXV4,        sensorI2CCustom)
#pragma config(Motor,  motorA,           ,             tmotorNXT, openLoop)
#pragma config(Motor,  motorB,           ,             tmotorNXT, openLoop)
#pragma config(Motor,  motorC,           ,             tmotorNXT, openLoop)
//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//

//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//
///----------------------------------------------------------------------------
/// didier  TWO MASTER SLAVE NXTBee modèle
//  NXT MARRON
///
///
///----------------------------------------------------------------------------

#include "drivers/mindsensors-ps2ctrl-v4.h"
#include "drivers/hitechnic-irlink.h"
#include "ROBOT DATA SPRAT 3 NXT ONE.h"
#include "didier GESTION SPRAT 3 NXT ONE.h";

///////////////////////////////////////////////////////////////////////////////

task main()
{
bNoPowerDownOnACAdaptor = true;   // will NOT power down when connected to AC adapter

bFloatDuringInactiveMotorPWM = false;  // the motors will NOT coast when power is not applied

StartTask (ROBOTData);
StartTask (gestionSPRAT);

while (true)
{
wait1Msec(10);
}
}

Want to see more pictures, videos, and information on these bots? Have any thoughts, comments, or questions? Check out Didier’s forum posts (links above) or comment below!

Written by John Watson

January 28th, 2013 at 4:00 pm