Thursday, December 18, 2008

Introduction to Robotics Experience

I feel that i have not learn't as much as i though i would in robotics.

During this time i have worked with robotics the construction have probably not been necessary for me. I know enough about constructing robots from the old Lego robotics to be able to build many things. I have for example built a robot that can climb on bars. I felt that this part was unnecessary for me to do.

The programing that we where supposed to use was to easy so i kept trying to take it up another step and develop more sophisticated programing then we where supposed to have. I haven't learn't a lot from the basics that we where supposed to work with. I have done other things like a avoidance program avoiding cans that are in the way.

The thing that i learnt most from was about the sensors. I learn't how to work with threshold and how to Detect, sense and most importantly interact with the enviornment. I have learnt most also from taking the tasks one step further then before.

Most of the time we have used Fysics (math in use) to predict behaviours and draw conclusions by observing what is correct. I feel that i haven't deepend my understanding in science or math here but i did have a slight improvement in my knowladge about technology but not as large as i would like.

In my view this course was to easy for me i needed to take a harder level of robotics

Tuesday, December 9, 2008

Tractor challange

This is our last challenge of the year. It is called the tractor challenge. WE are supposed to pull a sled with weights. For the tractor challenge we need to change the gears on our robot and program the robot so it is very slow to be able to move the weights.

Thursday, December 4, 2008

Drag race

Last class we had a drag race. In the Dragrace the robot was supposed to go 3 meter and win the race. So we had to make it as fast as possible. We tried a very high gear ratio. We did not have enough torque so the robot went slower. we had to pull down the gear ratio. As we did not have time to build a new robot we had to use the taskbot.

The picture is of the robot i would build and use if i had the time. It is generated in LDD. The wheels would be changed but LDD only has these wheels

Gears and Speed invistigation

In the gears of speed investigation we had two Hypotheses

First we find a value that we could compare the other values to. That means we tried to find Speed 1 and we used a number with the wheel ratio of 1 and running for 3 sec for gear ratio 1. We then measured the length of how long it traveled and the calculated the speed of the robot.

After predicted what the speed of speed 2 would be if gear ratio 2 is larger then 1 or smaller then 1. in both Hypotheses

When we tested how fast it went if the gear ration is larger or smaller then 1 we found that the values where closer to the prediction of hypothesis B. Then we reached the conclusion that hypothesis B is true and Hypothesis A is false

Monday, November 24, 2008

Get in Gear investigation and my presenation

Today i presented a presentation about values, numbers and the obstacle detection program it was about how to use values and numbers

Today we tried to increase the size of the driving gear and the driven gear. When we increased the driving gear and the driven gear the robot went faster.

When we did the opposite the robot went slower.

This is due to the trade between torque and speed.

Summary chapter 2 Gears

In chapter 2 it talks about gears. It talks about how to county teeth to get a gear ratio that you can use to convert speed to power (toque). The teeth in a gear is used to mesh with the other gear pushing making it spin. The tuque and velocity are different things one is the power the other is the velocity of the robot. to get speed you need a gear with many teeth that drives a gear with less teeth to get tuque you need the opposite with one gear with less teeth and the other gear with many teeth.

A gear that is useful is the worm gear because it can only move in one direction so if you are trying to lift a arm then the arm wont fall down.

Another wheel is the bevel gear that is used to change direction with between perpendicular axis.

The last wheel is the know wheel. That wheel is actually not a wheel it is a four pieces gear that one part that pushes the other parts

Thursday, November 20, 2008

Classic Projects (Chapter 14)

The most classic project to do is the detection of obstacles in a room. When doing this you need a couple of sensors. The ones that are used to do this is the Ultrasonic Sensor, Touch sensor and the light sensor. When doing this it is important to decrease the speed of the robot so it has a chance to register the object. Indirect obstacle detection is when for example a touch sensor is pushed until it is released so it rater detects the release then the push an "In Direct (not Direct)" It also talks about a steering follower. It is a steering assembly with a light sensor that keeps trying to follow a line and by doing that steering the robot after that line. It mentions some methods how to increase the speed. They are changing gears, Changing wheels and Decreasing weight. It is important o decrease gear slack because it can make the robot malfunction by the gears hacking and being damaged.