Skip to main content

Posts

Featured post

A* ALGORITHM BASICS FOR PATH FINDING & HEURISTICS METHODS : ARTIFICIAL INTELLIGENCE

 A* ALGORITHM BASICS FOR PATH FINDING A* , widely used  known form of best-first search & path planning algorithm nowadays in mobile robots,games. this is the function for A*,                                     f(n) = g(n) + h(n) g ( n ) is the cost of the path from the start node to n , and h ( n ) is a heuristic function that estimates the cost of the cheapest path from n to the goal This will find cheapest f(n) value in neighbor nodes to archive goal node. check below image  A to B path finding with g(n),h(n),f(n) value In the final level check below image Now we will check the Algorithm // A* Search Algorithm 1. Initialize the open list 2. Initialize the closed list put the starting node on the open list (you can leave its f at zero) 3. while the open list is not empty a) find the node with the least f on the open list, call it "q" b) pop q off the open list c) generate q's 8 successors
Recent posts

How to compile C++ file in ROS environment

let see how make one c++ file as executable or make it compile in ros environment let create one package call test so we will add test1.cpp to compile, then we have to change in 3 place in cmakelist.txt file here test1.cpp we named this executable as test1   add_executable(test1 src/test1.cpp)    add_dependencies(test1 ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})    target_link_libraries(test1    ${catkin_LIBRARIES}  )  these r the main changes we need to do in cmakelist. if we need to add another c++ file then let see  that's all lets compile for more details just check below video

ubuntu mate 18.04 remote RDP connection & ssh configuration fixed xrdp session: Login failed for display 0 in rasberry pi 3 B

This is for setup xrdp remote server sudo apt-get install xrdp This is for fixing Login failed for display 0 sudo adduser xrdp ssl-cert This is for enable ssh in rasberry pi and make it work to enable sudo raspi-config -> interfacing options -> ssh -> enable sudo rm /etc/ssh/ssh_host_* sudo dpkg-reconfigure openssh-server finally sudo reboot check this video

libga.a(garandom.o): relocation R_X86_64_32 against `.rodata' can not be used when making a shared object; recompile with -fPIC:ARGOS simulator

for this go to galib-master.zip folder dir if u dont have galib-master.zip then just download galib-master.zip file below link https://github.com/Robinroy-peter/swarmRobots    then open terminal inside first of all type below commands to remove galib previous compile sudo make uninstall sudo make clean then open makevars file inside the galib-master.zip , add -fPIC  with CXXFLAGS    = -g -Wall -fPIC  like that then copile it again with below commands make sudo make install  Then go to argos-example folder try to compile it follow below video guide if u need more information

ga/ga.h: No such file or directory: ARGOS simulator

for the error just download galib-master.zip file below link https://github.com/Robinroy-peter/swarmRobots and extract it in ur own dir, open a terminal inside the galib-master folder and compile it by typing               make              sudo make install Then go to argos-example folder try to compile it follow below video guide if u need more information

Genetic Algorithm Library (GAlib) Compiling Error Fixed(ga.h: No such file or directory) : ARGoS Simulator

 if you didn't try to setup argos just follow my previous post using below link Getting Started with ARGoS Large-Scale Swarm Robot Simulator in Ubuntu When you are facing below error while you try to compile argos in your ubuntu system galib_phototaxis_loop_functions.h:14:20: fatal error: /ga/ga.h: No such file or directory compilation terminated normally what we do?   we search this lib in google then we try to compile it but here if you download this GALIB lib from its official website from here http://lancet.mit.edu/ga/     its never work correctly because last update of this package 1999 so you guys need to change lots of c++ compiler based commands styles in many files so download the GALIB from this link  https://github.com/jibsen/galib    & compile based on that page instruction  finally  you need to change the  files location in argos examples follow the steps go  to /src/argos3-examples/loop_functions/galib_phototaxis_loop_functions/ and choose galib_pho

Getting Started with ARGoS Large-Scale Swarm Robot Simulator in Ubuntu

ARGoS (Autonomous Robots Go Swarming) is a multi-robot simulator designed to support large teams of robots. Its design is pretty different from the design of other simulators. Its most distinctive feature is that the 3D simulated world can be divided in regions, and each region can be assigned to a different physics engine. Furthermore, ARGoS' design revolves around the concept of tunable accuracy. In other words, in ARGoS, everything is a plug-in (robot models, sensors, actuators, physics engines, visualisations, etc) and the user can select which plug-ins to use for an experiment.  Since different plug-ins have different accuracy and computational costs, users can choose which plug-ins to use for each aspect of the simulation and assign resources only where it matters. This makes the simulation as fast as possible. At the time of writing, ARGoS supports the Swarmanoid robots (foot-bot and eye-bot) and the e-puck. ARGoS supports Linux and Mac OSX. Binary packages are availa

HASH TABLE : ADVANCE ALGORITHM

A hash table is an unordered collection of key-value pairs, where each key is  unique .  for each key value, hash function will generate the unique index then that key value will stored in that unique index as look like storing in normal array. so next what is Direct-address tables We shall assume that no two elements have the same key , to represent the dynamic set, we use an array, or direct-address table  here T is the hash table k is the key value DIRECT -ADDRESS -SEARCH (T, k)              return T [k] DIRECT -ADDRESS -INSERT (T, x)             T [key[x]] ← x DIRECT -ADDRESS -DELETE (T, x)             T [key[x]] ← NIL Each of these operations is fast: only O(1) time is required. Let have a look in HASH TABLE Collision resolution by chaining        if two elements have the same key  we put all the elements that hash to the same slot in a linked list CHAINED -HASH -INSERT (T, x)         insert x at the head of list T [h(key[x])] CHAIN

Translate