Introduction to Robotics - Final Entry

We've finally come down to our last blog entry...
Over the semester, the class has proved itself to be not only knowledgeable, but fun as well. Although tedious, Robotics has thought all of us the skills needed to plan, construct and program - we tend to explore new things and reach new heights within each class.
Throughout the semester, we've learned how to construct robots. We've learned that constructing a robot is harder than what one would think - it needs knowledge and reason of both the situation and surrounding the robot is in. Building a model that is suitable for the task at hand is the key to solving it. The position of sensors on a robot plays a significant role in the robot's performance, thus, considerations need to be made - by placing sensors at places that are most suitable for the task could easily serve as an advantage. Gear configuration is also significant to its performance as it controls the robot's "torque" - having a gear ratio that is a greater factor to the other gives a robot speed, while a ratio that is a lesser factor to the other gives a robot strength or power. Modular construction too is significant as it makes the robot "universally able".
What is a robot without a program? Nothing. We've explored the NXT programming software down until its "gut". We've learned how to easily program our robots to complete task that were given to us. Some of the common blocks we used were motor and wait blocks - they were like the very first step in learning how to program. We were forced to use other unique blocks due to increase of difficulty with each passing activity. One of my favorite blocks of course, is the switch block. The switch block enables the robot to think and decide based on either logic or sense.
In each kit we were given all kinds of sensors. Light, ultrasonic, touch, and sound; all were used, none were wasted. Without sensors, robots are not able to basically "sense". Sensors are significant to a robot's arsenal - each sensor had its own configurations and in order to make it sense what we wanted it to sense, we had to explore the settings. Overall, after all the programming and constructing, sensors are the eyes, hands, and ears of the robot.
In conclusion, Robotics has deepened our understanding of maths, science and technology through the constant contact with calculations and physics that were involved in this semester's class. We have also improved our reasoning, communication and collaboration with each passing challenge as it forced us to share ideas and think beyond what we usually know.

Tree Measurer - Construct

The tree measurer's design is apparently ideal for measuring objects that has the length/width of the space between the mobile caliper and immobile caliper. The robot's gear configuration (power from one motor) is significant to the movement of the caliper which allows it to measure an object; additonally, there is even a handle which makes it very easy to handle.

Overall the design is quite modular, however, the limit as to the size of the calipers* is a disadvantage.

Experience

Day 3 - Testing

Testing...

We planned to test our robot and our program (which should've been downloaded to the NXT block) on the course. It went pretty well, however, there were a few problems that i had to fix. My turning was not always perfect, but that can easily be solved. The biggest problem i had was on the last turning point - i wanted it to sense an object 20 centimeters away and maneuver around it, but i also wanted it to stop on the black line without sensing an object. I tried out many things with the switcher block, but still couldn't find out how to. I plan to research more and try my best to find out how to program my robot to maneuver the course with great accuracy.

Day 2 - Program

Today I plan to write a program for the challenge course. My program will have the necessary blocks for my robot to finish the course, finishing each challenge that comes in its way with ease. My program will be as follows:

Challenge 1 = Program robot to Start with a "clap" and stop for twenty seconds when it senses a low light value (lower than threshold set).

Challenge 2 = Use touch sensor to sense pillar (knock into pillar), then program to reverse and swing turn left.

Challenge 3 = Program forward and use ultrasonic sensor to sense desk, when it senses it, swing turn right.

Challenge 4 = Program robot to move forward, using the ultrasonic sensor again, sense the randomly placed object and swing turn right then left.

Challenge 5 = Move forward and sense low light value.

My robot design needs to be finished, as well as my program.

Obstacle Course Challenge

The obstacle course challenge might prove to be a difficult course to complete. The course itself is made up of 6 parts which are as follows:

1. Start (NXT) with clap.
2. There will be an outline of a box several centimeters away - program robot to stop within outline and wait for 5 seconds in order to proceed.
3. Bump into pillar, back up and turn right.
4. Sense Wall, turn right w/o touching it.
5. Avoid Obstacle. ---> not so sure how to program robot to pass the obstacle.

Experience - Line Tracking

The sum of knowledge gained from the few past classes is of great use as we got the chance to experiment with the light sensor as well as learn the behavior and configurations of the light sensor.
In order to learn about the light sensor, we were told to conduct an experiment using the sensor. The experiment is as follows: Robots must be programmed to follow a black line (on a white surface), "using" the light sensor - Line Tracking.
My partner and I first attached the light sensor to the front of the robot; however, we found out that placing the light sensor at the back of the robot, closer to the two wheels, is better because the light sensor will create smaller swing turns, minimizing the chance of the robot going off course during the experiment; additionally, it helps the robot to follow the line at a greater speed. Now on to programming, in order for the the robot to proceed along the black line, we programmed it to make right and left swing turns depending on whether the sensor reads a light value that is less or greater than the threshold set (the threshold is the average of both light and dark readings - test on NXT).


Program: