Pepper Robot Tour - Smart Navigation - linux

Thanks in advance for your help! The main question boiled down is this: What kind of solutions are there for getting Pepper to navigate her environment intelligently?
We are interested in having her lead a tour through our facility. The problem persists however that she will not correct her course over long distances, leading to her drifting to the left or right over time, hitting walls, and breaking her code. To try and get her navigating intelligently, we've pursued 3rd party solutions like SPQREL navigation: https://github.com/LCAS/spqrel_navigation/wiki/NAOQI-Installation-and-Usage but realized that running gmapping from ROS to get the .yaml environment map file is seemingly not possible on Pepper, and the file is best generated with another robot first.
We're running a windows system with linux subsystem and have made direct connection to the robot. What can we combine with our pepper tour in Choregraphe to make her drive straight down a long hallway?

The Pepper robot navigation is not suited for practical use. The platform is too unstable to move at a human pace, and the sensors are not reliable enough to navigate a live environment.
You can try for yourself with this sample:
https://github.com/aldebaran/naoqi_navigation_samples
And here is the documentation for the API:
http://doc.aldebaran.com/2-5/naoqi/motion/alnavigation-api.html?highlight=navigate

Related

Fatal Python error: (pygame parachute) Segmentation Fault Error [duplicate]

I need to do some basic networking for a Pygame project.
Basically, it's a 2D single player or cooperative game. The networking only needs to support two players, with one as a host.
The only information that needs to be sent is the positions of players, creeps and bullets.
I've been reading around and Twisted keeps coming up, but I haven't done networking before, and I'm not sure if that might be an overkill.
So, is it possible for a relative newbie to implement networking in Pygame?
This was asked recently on Reddit, so I'll more or less just copy my answer over from there. I apologize for not being able to provide more links, I have <10 rep so I can only post two at a time.
Twisted might work, but I don't have a whole lot of experience with it. I'd recommend going with sockets, as that's what Twisted uses in the background anyway. Beej's guide (google it) is pretty much the Holy Bible of sockets if you want to learn how they work (in C++, but the concepts extend everywhere). Python does abstract some of the complexity away, but it's still a good idea to know what's going on in the background.
For Python specific sockets, you can go ahead and just use the howto (user745294 posted a link above). Here's a nice article titled "What every programmer needs to know about Game Networking". It goes into the different types of major networking styles (client-server, p2p, udp v. tcp, etc.) and the history behind what some major games used for their networking.
Below is a link to a demo I did on making a networked "game" in Python 2.6/Pygame. It's not actually a game, but each client you create connects to the server and controls a character. You can move your character with the arrow keys and the character will move on all connected clients. I tried commenting the source code with some indication of what I'm sending back and forth, but you may need a little knowledge about sockets to understand it.
The source code is provided in the codepad links in the comment below this post. You will need to provide two images in the same directory as the scripts:
bg.png is the background sprite. It should be an image 400px wide and 300px tall (this can be changed in the GameClient class if needed)
sprite.png is the player character. It should be smaller than the background so that you can see it moving around.
You can use Twisted for networking with Pygame. The "game" project on Launchpad has some examples of how one might integrate the main loops together; basically, use twisted.internet.task.LoopingCall to draw Pygame frames and handle input, while letting the Twisted reactor of your choice run normally.
Since you are already using Pygame, I think this light networking library made for Pygame will do what you need and teach you, but not overwhelm you.
"Mastermind Networking Lib" via pygame.org
There is Pyro (Python remote objects) as another solution for networking in Python.
http://irmen.home.xs4all.nl/pyro/
Using raw sockets is low-level and full of danger. As said before, Twisted is complex and takes to time get up and running. To save yourself some headaches I'd try something like zerorpc.
You need the following solutions:
discovering other player(s) on the (local) network, you don't want player to enter some IP address
handle network errors
serialize messages containing your data (positions, player name, etc.)
handle threading as networking is asynchronous I/O
Above should still be called 'basic', you should really use some fancy networking library with idiomatic API.
Essentially you need to expose the network service (in its own thread) that will push messages to Python's Queue, and then access this same queue from your Pygame code, and if there is a message then you update whatever structures you use to store player's position and draw it on screen.
You shouldn't send stuff like bullet positions over the network as they can be easily (and faster) calculated locally. You just send an event like bullet_shot over the network with a source position and velocity vector.

Flinto / Sketch: Exporting or sharing animations

I'm new to Sketch and Flinto but have come up to speed after prototyping fully functional designs in HTML, CSS and JS.
Q: If you build a prototype with Sketch and Flinto, how can you export or save it so that others without Sketch can view it? Is that even possible?
PS: Additionally, where could I find a good online course (free or paid) about "Sketch 4 from srcatch for beginners"? I have looked and googled, and I purchased the Udemy course (but even though they say it's OK for beginners, they jump right in, making a lot of assumptions about knowing Sketch already.
There are a lot of ways to share your Sketch project, it depends if you want to share your prototype with the client or hand your deliverable to the developer.
I recommend using Invision, it is an online tool, you don't have to download any software, you just share your project with a link. With a free account it allows just one active project at a time, but if you want to upload a new project you can just store the old one. Invision is a great tool for both clients and developers, who can see the interactive prototype with transitions and animations, make comments, and view the code with inspector.
Another great tool for handing the deliverables to developers is Zeplin.
About Flinto, to share your prototypes you can record the preview window and share the mov/gif file, or you can share the flinto file to a phone and open it with the Flinto viewer app.
There are a lot of transitions that can be done with Sketch plus the plugin Craft, maybe you don't even need to use another tool like Flinto.
To learn about Sketch there are a lot of youtube channels I can recommend: Sketch Together, Joseph from LearnSketch.com, Jesse Showalter, CharliMarieTV, The Futur.
Hope this was useful! Keep on learning!

Gesture Recognition for my Grandma (Kinect) Linux

I'm looking into making a project with the Kinect to allow my Grandma to control her TV without being daunted by using the remote. So, I've been looking into basic gesture recognition. The aim will be to say turn the volume of the TV up by sending the right IR code to the TV when the program detects that the right hand is being "waved."
The problem is, no matter where I look, I can't seem to find a Linux based tutorial which shows how to do something as a result of a gesture. One other thing to note is that I don't need to have any GUI apart from the debug window as this will slow my program down a fair bit.
Does anybody know of something somewhere which will allow me to in a loop, constantly check for some hand gesture and when it does, I can control something, without the need of any GUI at all, and on Linux? :/
I'm happy to go for any language but my experience revolves around Python and C.
Any help will be accepted with great appreciation.
Thanks in advance
Matt
In principle, this concept is great, but the amount of features a remote offers is going to be hard to replicate using a number of gestures that an older person can memorize. They will probably be even less incentivized to do this (learning new things sucks) if they already have a solution (remote), even though they really love you. I'm just warning you.
I recommend you use OpenNI and NITE. Note that the current version of OpenNI (2) does not have Kinect support. You need to use OpenNI 1.5.4 and look for the SensorKinect093 driver. There should be some gesture code that works for that (googling OpenNI Gesture yields a ton of results). If you're using something that expects OpenNI 2, be warned that you may have to write some glue code.
The basic control set would be Volume +/-, Channel +/-, Power on/off. But that will be frustrating if she wants to go from Channel 03 to 50.
I don't know how low-level you want to go, but a really, REALLY simple gesture recognize could look at horizontal and vertical swipes of the right hand exceeding a velocity threshold (averaged). Be warned: detected skeletons can get really wonky when people are sitting (that's actually a bit of what my PhD is on).

J2ME app menu develop

I'm developing a small j2me game and i want to create a menu for this application. I imagine the menu as a vertical list of items with a cursor on the left or right side that i can move from item to item, something like this menu example but as a main menu.
What elements should i use to obtains such effects? I need only advices or links, i will develope it myself.
Thanks in advance!
import java.util.Vector;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
What you plan looks doable. Can't give much links because don't recall any that could help on stuff like you're doing. Actually, most useful link for you will probably be MIDP (JSR 118) API reference - your part is going to be mostly lcdui package, and especially Graphics API.
As for advice, no problem. First thing to note is that there will be more coding and more (much more) testing/debugging than it was in your prior experiment with implicit list. If you can think of some possible deadline / timing requirements that may become a problem - just keep in mind that prior design with implicit list as a fallback. It won't look as fancy but it'll work work safe and correct.
Another important thing is to decide what kind devices you are going to target. For menu like one you are going to develop, it may be rather difficult to get consistent look and feel both at 160x200 basic phone with ITU-T keypad and on 400x600 touchscreen smartphone. Below I am going to assume you'll try to target as wide variety of devices as possible - note the narrower you can get it, the easier it will be to code and test.
When targeting lots of different devices it is helpful to use an emulator that can be configured to simulate various display sizes and resolution, presense or absence of touchscreen input etc. Keep in mind though that emulator alone won't fully simulate real device. To keep your feets on the ground, consider also some regular smoke testing of your application with real device, preferable using over-the-air (OTA) installation.
Here are some particular API tips that I can think of now.
Use Canvas.getGameAction to handle pressed key code - that is likely the most reliable/portable way to figure up/down and select actions for menu.
Use Canvas.hasPointerEvents to figure if there's touch screen support. Users with touch screen devices may get disappointed if it turns out that your fancy menu can't react when they tap on screen.
Use Font.getHeight and Font.stringWidth to figure how much space is occupied by menu item text.
Use Image.getGraphics if you want to draw something over the image object.
As I mentioned, you most likely will do a lot of stuff using lcdui.Graphics API. It's mostly rather simple, but you will probably need to understand somewhat tricky stuff about clipping. Good luck.

Major game components

I am in the process of developping a game, and after two months of work (not full time mind you), I have come to realise that our specs for the game are lacking a lot of details. I am not a professional game developper, this is only a hobby.
What I would like to receive help or advices for is this: What are the major components that you find in games, that have to be developped or already exists as librairies? The objective of this question is for me to be able to specify more game aspects.
Currently, we had specified pretty much only how we would work on the visual, completely forgetting everything about game logic (AI, Entities interactions, Quest logic (how do we decide whether or not a quest is completed)).
So far, I have found those points:
Physics (collision detection, actual forces, etc.)
AI (pathfinding, objectives, etc.)
Model management
Animation management
Scene management
Combat management
Inventory management
Camera (make sure not to render everything that is in the scene)
Heightmaps
Entities communication (Player with NPC, enemy, other players, etc)
Game state
Game state save system
In order to reduce the scope of this queston, I'd like it if you could specifically discuss aspects related to developping an RPG type of game. I will also point out that I am using XNA to develop this game, but I have almost no grasp of all the classes available yet (pretty much only using the Game component with some classes that are related to it such as GameTime, SpriteBatch, GraphicDeviceManager) but not much more.
You have a decent list, but you are missing storage (save load), text (text is important in RPGs : Unicode, font rendering), probably a macro system for text (something that replaces tokens like {player} with the player characters name), and most important of all content generation tools (map editor, chara editor, dialog editor) because RPGs need content (or auto generation tools if you need ). By the way have links to your work?
I do this exact stuff for a living so if you need more pointers perhaps I can help.
I don't know if this is any help, but I have been reading articles from http://www.gamasutra.com/ for many years.
I don't have a perfect set of tools from the beginning, but your list covers most of the usual trouble for RUNNING the game. But have you found out what each one of the items stands for? How much have you made already? "Inventory Management" sounds very heavy, but some games just need a simple "array" of objects. Takes an hour to program + some graphical integration (if you have your GUI Management done already).
How to start planning
When I develop games in my spare time, I usually get an idea because another game lacks this function/option. Then I start up what ever development tool I am currently using and try to see if I can make a prototype showing this idea. It's not always about fancy graphics, but most often it's more about finding out how to solve a certain problem. Green and red boxes will help you most of the way, but otherwise, use Google Images and do a quick search for prototype graphics. But remember that these images are probably copyrighted, so only use them for internal test purposes and to explain to your graphic artists what type of game/graphic you want to make.
Secondly, you'll find that you need to find/build tools to create the "maps/missions/quests" too. Today many develop their own "object script" where they can easily add new content/path to a game.
Many of the ideas we (my friends and I) have been testing started with a certain prototype of the interface, to see if its possible to generate that sort of screen output first. Then we build a quick'n'dirty map/level-editor that can supply us with test maps.
No game logic at this point, still figuring out if the game-engine in general is running.
My first game-algorithm problem
Back when I was in my teens I had a Commodore 64 and I was wondering, how do they sort 10 numbers in order for a Highscore? It took me quite a while to find a "scalable" way of doing this, but I learned a lot about programming too.
The second problem I found
How do I make a tank/cannon fire a bullet in the correct direction when I fly my helicopter around the screen?
I sat down and drew quick sketches of the actual problem, looked at the bullet lines, tried some theories of my own and found something that seemed to be working (by dividing and multiplying positions etc.) later on in school I discovered this to be more or less Pythagoras. LOL!
Years and many game attempts later
I played "Dune" and the later C&C + the new game Warcraft (v1/v2) - I remember it started to annoyed me how the lame AI worked. The path finding algorithms were frustrating for the player, I thought. They moved in direction of target position and then found a wall, but if the way was to complex, the object just stopped. Argh!
So I first sat with large amounts of paper, then I tried to draw certain scenarios where an "object" (tank/ork/soldier) would go from A to B and then suddenly there was a "structure" (building/other object) in the pathway - what then?
I learned about A-star pathfinding (after solving it first on my own in a similar way, then later reading about the reason for this working). A very "cpu heavy" way of finding a path, but I learned a lot from the process of "cracking this nut". These thoughts have helped me a lot developing other game algortimes over time.
So what I am saying is: I think you'll have to think more of:
How is the game to be played?
What does the user experience look like?
Why would the user want to come back to the game?
What requirements are needed? Broadband? 19" monitor with 1280x1024?
An RPG, yes - but will it be multi-user or single?
Do we need a fast network/server setup or do we need to develop a strong AI for the NPCs?
And much more...
I am not sure this is what you asked for, but I hope you can use it somehow?
There are hundreds of components needed to make a game, from time management to audio. You'll probably need to roll your own GUI, as native OS controls are very non-gamey. You will probably also need all kinds of tools to generate your worlds, exporters to convert models and textures into something suitable for your game etc.
I would strongly recommend that you start with one of the many free or cheap game engines that are out there. Loads of them come with the source code, so you can learn how they have been put together as you go.
When you think you are ready, you can start to replace parts of the engine you are using to better suit your needs.
I agree with Robert Gould's post , especially about tools and I'd also add
Scripting
Memory Management
Network - especially replication of game object states and match-making
oh and don't forget Localisation - particularly for text strings
Effects and effect timers (could be magical effects, could just be stuff like being stunned.)
Character professions, skills, spells (if that kind of game).
World creation tools, to make it easy for non-programmer builders.
Think about whether or not you want PvP. If so, you need to really think about how you're going to do your combat system and any limits you want on who can attack whom.
Equipment, "treasure", values of things and how you want to do the economy.
This is an older question, but IMHO now there is a better answer: use Unity (or something akin to it). It gives you 90% of what you need to make a game up front, so you can jump in and focus directly on the part you care about, which is the gameplay. When you run aground because there's something it doesn't do out of the box, you can usually find a resource in the Asset Store for free or cheap that will save you a lot of work.
I would also add that if you're not working on your game full-time, be mindful of the complexity and the time-frame of the task. If you'll try to integrate so many different frameworks into your RPG game, you can easily end up with several years worth of work; maybe it would be more advisable to start small and only develop the "core" of your game first and not bother about physics, for example. You could still add it in the second version.

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