Chapter 1, Foundation for Advanced Robotics and AI

1. PID stands for Proportional, Integral, Derivative, and is a type of closed loop controller which does not require a model to operate. PID is not an AI method because it doesn't involve learning and there is no simulation of decision making.
2. The Turing test, originally called “The Imitation Game” by Alan Turing, is an imaginary test, or thought experiment, in which a person is communicating with someone or something via a teletype (text message for you millennials). An AI would pass the Turing test if the person was unable to tell if the entity he/she was communicating with was a human or a robot. The Turing test has been pretty much smashed by modern AI-based chatbots, and a new test has been proposed – assembling IKEA furniture via the directions.
3. Because they cannot see them completely with a range sensor, such as a LIDAR. Also, most robot obstacle detection sensors are parallel to the floor and are not looking down.
4. In the Orient step, all of the data is put into the same reference frame, which is usually the robot’s central point of view. This allows the robot to determine which data is relevant to decision making.
5. This is a bit of a rhetorical question. The correct answer is "a lot". Using Python as an interpreted language can save a lot of time for very complex builds, where a C / C++ compiler and link can take 20 minutes or more. The C program test cycle in the question would take 6.25 hours to complete while Python would take 2.5 minutes.
6. RTOS stands for Real-Time Operating System.
7. You need a number that all of the rates 10, 5, 50, 20 divide into evenly. The smallest number that fits is 100 Hz. I would also accept 50 Hz if the student assumed that the 20 Hz would update twice in one frame and three times in the next frame.

8. As given in the previous questions, there does not have to be the same number of samples in each frame in order to come out with a constant frame rate, as long as there is a multiple of the base frame rate every sample divides into. In this case, 20 x 7 = 140, so the 7 Hz can run in a 20 Hz base rate, and it will repeat patterns every 140 frames, or 7 seconds. 3.5 is half of seven and can run at the same base rate with a pattern that repeats every 70 frames or 3.5 seconds. Each update would be 5.7 frames apart, which gets rounded up to 6.
9. A blocking call suspends the execution of your program until some interrupt or event occurs, such as receiving a datagram or UDP packet. They are bad because you lose control of your program timing and cannot maintain a soft real-time execution. Use polling type calls instead for serial ports and network interfaces.