Skip to main content

Matthew - Capstone Blog Post 2

In Towards Integrated Imitation of Strategic Planning and Motion Modeling in Interactive Computer Games, Dublin City University researchers Bernard Gorman and Mark Humphrys detail their experiments in using imitation learning techniques to teach an artificial agent to play a first person shooter—in this case, Quake—in a way that would convince onlookers and other players that it is human. They describe a superior agent, which imitates "the observed goal-oriented behaviors of a human player," (p. 2) in order to play with competence, exhibit strategic thinking, and employ "believably human-like motion" (p. 1). In other words, they want to create a bot that can pass a kind of Turing deathmatch.

Gorman and Humphrys describe the behavior model which serves as the basis for their work. The model specifies several levels of control, where each level corresponds with roughly how much time the agent has to form a plan. These range from immediate ("scrambled control") to long-term ("strategic control"). Furthermore, their model relates these levels of control to three kinds of behavior—strategic, tactical, and reactive—which together are supposed to form the building blocks for an agent's motion modeling capabilities (p. 3).

In their experiments, Gorman and Humphrys emphasize the "human-like motion" mentioned above. Specifically, they limit their agent's problems to those of environmental navigation and item acquisition. Their methods involve topology learning (p. 3), Markov decision processes or MPDs (p. 4), and motion modeling based on "action primitives." The action primitives, the recorded gameplay, and relevant state space information comprise the training data (p. 6-7). They applied their agent in two types of tests: "pickup sequence" tests, in which the agent must pick up a series of items, and "continuous gameplay" tests, which were of a more free-roam nature (p. 8-9). The researchers noted that the agent performed "showed impressive performance and adaptability" during the pickup sequence tests (p. 8). Otherwise, they noted one issue in the continuous gameplay tests: the agent would sometimes struggle to choose among competing utilities (p. 10-11).

Gorman and Humphrys note in their conclusion that their work relates closely to that of Christian Thureau of Bielefeld University. They mention several works from this author throughout the paper. Please consider joining me next time as I explore this researcher's work.

Comments

Popular posts from this blog

Rei - Blog Post 10

So,  I missed blog post 9. This is me acknowledging that for consistency. Anyway, the past couple of weeks have been incredibly productive for ContentsMayBeHot. Matthew has finished collecting all the replay data, we have refactored our project to reduce complexity, we have improved the runtime of our code, and finally we have started seriously training our model. The Changes Matthew implemented multi-threading for the model loading. Which reduced our load time between files from about 3-5 Seconds to 1 Second or less. Which allows us to fully train a model in much less time! While Matthew did this I reduced the code duplication in our project. This way, if we needed to change how we loaded our training data, we didn't have to change it in multiple places. This just allows us to make hot-fixes much more efficiently. We also started working on some unittests for our project using pytest. These tests were written because of a requirement for another class, but we thought it...

Matthew - Blog Post 9

After our last meeting, Professor Auerbach asked us to shift our focus towards building and training our model. So that's what we've been working on lately. The results so far have been interesting and problematic. The first step was to define a minimal working model and a loading system to feed it our labelled data-set. I wrote a Sequence subclass, which is essentially a kind of generator designed for use with the fit_generator method. With fit_generator and a sequence, we're able to train and test the model with just a couple of one-liners: model.fit_generator(sequence) model.evaluate_generator(sequence) The sequence subclass also has a few other tricks up its proverbial sleeve. For one, it reduces the dimensionality of the frame buffer data from 135×240×3 to 135×240×1 by converting it to gray-scale. This reduces the number of features from 97,200 to 32,400. For two, it does the same with the labels, combining and dropping 26 action types into just 9 atomic clas...

Rei - Blog Post 4 & 5

Due to external factors, I accidentally missed the last Blog Post, however I shall make up for it by writing two posts in one! The last couple of weeks have been at least a little productive. Blog Post 4 Over these weeks, Matthew and I were both working on solidifying and exploring the context portion of our project. Of course, we have been exploring the context since nearly the beginning of the year, but because of both capstone classes have asked us to write something about the context of our paper. The context of our project can be found throughout our previous blog post, but a short and summarized version of out context section boils down to a couple main points.  Neural Networks are not too present in video games. When neural nets are present, they are used for research or marketing. As for the rest of our Design Document, unfortunately we rushed it a bit. We got caught up in some upsetting events these weeks and allowed our work to suffer instead of staying on t...