5-2-2012

Today we presented our final robots to the class.  Everyone went and explained what their robot was supposed to do, what problems they encountered and gave a demonstration of the robot.  I felt that mine did fairly well considering everything.  The line followers were giving me trouble, the robot would shake back and forth as it moved along and sometimes it would get it self stuck and I would have to give it a bump to start it back up again.  The IR sensor and arm worked as intended though, which I was happy about.  I have a short video of the robot below.  Since I didn't have a miniature garbage can for it to sense and pick up I used my hand to let it know there was an object there.

4-30-2012

Today's class was dedicated to working on our project two.  Today I was having trouble getting my line followers to work correctly.  For a while the right and center line followers were not giving good values between white and black.  Eventually I saw that part of the sensor was sticking out of the plastic case, so I pushed it back inside and then they started giving better values.  But they still act strange when I put the robot on the table.  It would just sit still for a few seconds and then shoot forward without stopping or making turns.  I did find out what value the IR sensor would have to read in order to stop the robot in a position so the claw can grab an object.  I also think that I will need to slow the robot down.  I think that is a reason for it not making turns or stopping in time, it's moving too fast.  I will need to play with the values going to the motors until I find one that will have the robot going at a more appropriate speed.

4-25-2012

Today we spent the beginning of class learning about the different types of gears and how to do different calculations involving gears.  The rest of class was used for us to work on our robots for our project two.  I finished the wiring for all the components for my robot.  I started to to work on getting the arm on top of my robot to work, when to two servomotors at the base of the arm stopped working.  It looked like the connector the goes from the servomotor to the actual arm was stripped out, and the other motor stopped working altogether.  I took them both off the arm and Dr. B took them home to look at them.  I also started writing the program for other parts of the robot.  I forgot to take some pictures of my progress today.

4-23-2012

Today class was devoted to working on our project #2.  I finally came up with an idea for the project.  I'm going to have the robot follow a line, while having a sensor on the side that will look for "garbage cans."  When the robot finds one it will stop and an arm will extend and grab the can, lift it up and dump it into a bin, then put the can back on the ground and continue down the path.  The real world application for this would to have the robot follow a curb or sidewalk, looking for trash cans.  Dr. B gave me a pre-constructed arm to use to grab the cans.  I mounted the arm today as well as attached the line follower sensors and IR sensor to find the cans.  I will need a separate battery to run the arm because it will draw too much current from the board.  I still need to wire everything into the board as well.   Hopefully I can do that next class period, then begin to program it.  I also cleaned up the wiring involved with the Banebot, switch and battery.

Cleaned up my previous wiring

Mounted arm, line follower and IR sensor

IR sensor

Arm

Arm

4-18-2012

Today we started class by learning about pneumatics.  We spent about an hour learning about the different types of linear and rotary actuators and a few of the different types of valves.  After the lesson we worked on our robots for the rest of the class.

LCD display

IR receiver

4-16-2012

Today's class was dedicated to working on our robots.  I worked on getting the HB 25 and Banebot wired and programed.  I also wired in a master switch to turn on and off the power from the new battery to the board and motors.  The Banebot worked fine, but the HB 25 gave me trouble.  Dr. B came and tried to figure out why it wouldn't turn the motor.  We checked the program, wiring and the motor controller itself but it turned out to be that we had to start with the master power and switch on the board both off, then turn on the master power, wait a few seconds then turn on the board and it would work.  No body knows why it did that.  After that I got my LCD display for the next project.

4-11-2012

Today we took a test at the start of class.  Then we were free to work on our assignments.  I picked out the new robot I wanted to work with for rest of the semester.  It is basically a shell with two motors, and we will wire in the components.  We were given a Parallax HB 25 motor controller and a well as a Banebot motor controller.  Our assignment is to wire in and program them to each run one of the wheels on the robot.  During class I disassembled the ultrasonic sensor from the previous assignment and moved the circuit board from my smaller robot to the bigger one.  I then attached the wires I'll need onto the HB 25.  That was as far as I got today, but I brought home the robot to work on before next class.

New robot body

New robot body

HB 25 (far left), connection wires, HB 25 cover and Banebot (orange)

HB 25

New robot body with circuit board mounted, HB 25 in cover (right), and Banebot (bottom)

4-9-2012

Today in class we went over what we will be doing for the rest of the semester and what we will be doing after we are done with the ultrasonic sensor.  I spent the rest of the class getting the sensor to work.  the video below show the robot navigating around and making turns as it finds walls.  The robot is supposed to look forward and if it doesn't see anything within five inches it moves forward. When it sees something it stops, the sensor looks left then scans again.  If there's nothing, it turns left and goes forward.  If there is something it looks right and scans again.  If there's nothing it makes a right turn.  If there is something in front and to the left and right of the robot it will turn around.  My timing on the turns wasn't exactly on, so the turns aren't as precise as they should be.

4-4-2012

Today the class time was dedicated to working on getting the ultrasonic sensor to operate.  I finished assembling the sensor and servo motor and attaching it to the robot.  Then I worked on the program the rest of the class time.  I didn't finish but I should be able to finish on Monday.

Finished assembly

4-2-2012

Today in class I finished the project with the line followers and inferred sensor.  The robot worked very well, and followed the line without problem. After that I received the parts that we will be using for the next project, which will involve an ultrasonic sensor.  I took off all the sensors from the previous project and started to assemble the parts for the ultrasonic one but I didn't finish before class ended.  The kit consisted of an ultrasonic sensor, servomotor, brackets and nuts and bolts.  The servomotor is supposed to be mounted to the front of the robot, which a bracket attached to that, with the ultrasonic sensor attached to the top of the bracket.

 The video below shows my robot following the black line around the table and stopping when it senses something in front of it and stopping when it senses all black at the end.

Kit for the ultrasonic sensor

Larger holes drilled in the left and right wings of the servo motor

Ultrasonic sensor

3-28-2012

Today in class we had the majority of the time to work on getting our line followers and inferred senors to work.  Towards the end of the class I manged to get my robot to follow the line, but there were a few things that need fine tuned.  Most of the class needed more time to work, so on Monday we will have some time to work more.  Hopefully I will be able to get the robot to run smoothly and do an official test run.

3-26-2012

Today we used the beginning of class to go over case statements to use in our program and went over everything we will need to have in our program to use the line followers and inferred sensor.  I finished mounting the line followers and inferred sensor to the body of the robot, then began working on writing the program.  I wasn't able to finish and will have to work on it next class.

Front view of mounted line followers and inferred sensor

3-21-2012

Today in class we spent about half of the time talking about batteries.  We learned how they can be categorized, such by voltage, chemical makeup, configuration of cells and a few other ways.  we learned how to calculate voltage and capacity of batteries if their cells are in either series or parallel.  We talked about the discharge rate and how that effects battery life.  We also learned about some characteristics of the different chemicals used in batteries, and that some chemicals allowed batteries to be recharged as well as have what is called memory effect, which occurs if you recharge some batteries before they are drained, which shortens their life.  After we finished talking about batteries we went on to how we were going to wire in our line follower sensors.  For the rest of the class time we wired in the line followers and wrote a short program so we could test them to make sure they worked.  I wired in the sensors but I didn't attach to bracket that holds the sensors in place below the robot yet.

Side view of robot

Top view of senors wired in

Front view

3-19-2012

Today in class we learned about inferred sensors and their uses.  They are used to detect distances and give feedback.  We were each given an inferred sensor to connect to our robot.  We wired them onto our robots and then wrote a simple program that would have the sensor detect a distance and then display it in a window in the Picaxe program while the robot was still plugged in.  But the numbers it would display were not in inches or centimeters, so we had to figure out a formula that would give us the correct number, which I didn't finish before the end of class.  But after a while we moved on to the line follower sensors that were in our kits and talked about how we were going to install them in our robots.  You can see in the pictures below the steps I took in preparing the senors. First I trimmed the leads of the sensors so they were a little easier to work with.  Then I soldered pieces of wire onto the end of each lead.  After that I put heat shrink over each of the solder joints to prevent them from contacting each other and to strengthen the joint.  Next I put pin crimps one the other end of the wires so they can be easily plugged into the board.  Last, I put pairs of the crimped end into sleeves to keep them organized and make plugging them in easier.

Inferred sensor

Line Follower sensors

Sensor with trimmed leads and wired soldered on

All three sensors with wires soldered on

Heat shrink put over the solder joints

Crimps put on to other end of wires

All the crimps put on

Crimped end put into sleeves

Finished sensors

3/7/2012

In class today we spent the majority of the time discussing sensors.  We went over the different types of senors, analog and digital and the different kinds of sensors that fall into those categories, such as inductive, capacitive, optical, thermistors, light sensors, and line followers.  We went over the different ways that sensors can be categorized, such as contact and non-contact, active and passive, temperature, position, and load.  The we talked about how we would need to wire sensors onto our board using the Picaxe as well as things we could do within the program that will help us in the future when we start to use senors move heavily.  Then we were given two Bumper Switches to wire onto our boards.  Then in Picaxe we wrote a program that would display in words something to the effect of "the switch is pressed" in a window on our laptops when the switches had been pressed.  We learned to use binary that corresponds with ports on our board to make it easier to program AND statements and also how to use a mask in case we have other inputs in a port that aren't sensors or are different sensors.

Front view of the Bumper Switches

Side view of the Bumper Switches wired in.

3/5/2012

Today in class we were given a task to work on for the duration of the class time.  Our task was to complete seven straight sections of the maze we used in previous assignments.  But to make it different for each student we were each given an intersection of the maze to start at and if two students started at the same intersection, one went towards the Start of the maze and one towards the Finish.  So, a student might start in the middle and go towards the Finish, but it might only take four straight sections to reach the Finish, so the robot would have to turn around and complete two more sections.  We were allowed to use speed control if we wanted but it wasn't required.  We also had to have the robots make the turns by pivoting with both wheels, in order to demonstrate that we could program the wheels to go backwards, instead of making of turn with one wheel turning and one stationary.  My robot was able to complete the sections with a few minor manual corrections during the run.  Dr. Bronakowski said that was fine and I received credit.  I unfortunately forgot to take video of my robot during the run.

2/29/2012

Today in we went over the uses for the L293 driver.  The L293 will allow us to have directional control over our motors in our robots.  We then wired our robots to just test the directional control not using the micro controller.  Mine worked when I switched the wires on the L293.  Then we wired in the micro controller with the L293 so we could have speed control.

View of the final wiring

Top view of the robot wired up

 

The above video shows the robot going back and forth and making turns using directional control

                                                          

2/27/2012

Today in class we spent the time finishing up our programs so our robots will write our initials on the floor.  The letter my robot had to write were CJW.  Over the weekend i disassembled the right wheel and reassembled it, being more careful to make sure the motor mount wasn't rubbing any of the exposed gears on the motor.  Today when I went to test the robot both wheels worked fine, so I suppose that reassembling the motor worked.  We also received a new power cord with a smaller diameter that fits better in the power terminal on our circuit board.  I made small adjustments to the program and did an official run at the end of class. 
           The three pictures below are different angles of my finished robot

This video is of the robot making CJW.  The letters are formed more vertically than horizontally. 

2/22/2012

Today in class we discussed how to use drivers to power devices that require more power than the microcontroller can supply.  We also wired in some LEDs on our bread boards and used pwnouts to make then dimer and brighter.  Then our next assignment was to program the robots to write our initials on the floor while incorporating speed control.  I ran into some trouble though because the right motor wasn't responding well when it wasn't receiving full power.   Once I reduced it's power it would lag much more than what was programmed.  Dr. B. suggested a few things I could try to identify the problem but I'll have to work on them over the weekend.

LEDs wired in from the microcontroller to the driver

2/20/2012

Today in class we dissembled out robots from the previous assignment.  We removed to servo motors we were using and installed gear motors. We solder wired onto the leads of the motors as well as a capacitor going across the leads.  The other ends of the wires were put into crimp pins and then put into a 2 pin connecter so they can be plugged into the breadboard. We also discussed Brushed DC motors and Brushless DC motors, how they work and the differences between them.  We also talked about the different kinds of brushless DC motors such as step and half-step motors.

New motors with wires and capacitors soldered on

Top view of robot with old wiring removed and the other breadboard added

Rear view of new motors.

2/15/2012

Today in class I finished programing my robot to go through the maze.  I had to program in the final straight shot.  Then I wired in the buzzer onto the breadboard and programed it to make a short beep once it reached the end of the course.  The first video below shows the robot making it way through the course.  After we tested the robots we went over new material in class.  We went over the "dirs" command to help simplify our program went we have a lot of outputs we need to turn on and off.  The second video shows some LEDs being turned on and off in a loop in a simple program using the dirs command.

2/13/2012

Today the class time was dedicated to programing our robots to navigate through a maze.  We had to use time when programing the robots, which means instead of using sensors or speed control we had to tell it to go forward and left or right for a certain number of seconds.  This method can take time because you basically have to make an educated guess as to how long to tell the robot to go forward, program that, then test.  The series of directions in the maze are, straight, right, straight, left, straight, left, straight, right, straight, right, left and finally straight to the finish.  Once I created the subroutines for it, it was just a matter of putting them in the correct order and with the correct times.  When class ended I had all of the turns expect for the last one programed and timed.  During next class I'll have to finish that last turn as well as wiring in and programing the buzzer that is supposed to sound when the robot reaches the end of the maze.  The video below is a recording of one of the many test runs I did during class today.  I had the robot programed to navigate about half of the maze at that point.  You will see that if definitely needed some tweaking.

2/8/2012

Today in class we were given motor and motor mounts that were not included in our kits.  We attached those onto the robot body.  We discussed how to make connections from the PICAXE to the motors by using the breadboard.  We also talked about wiring in the buzzer.  After that we discussed bits, bytes and words and the differences and uses for each when programming.  After that we worked on wiring the motors to the PICAXE. 

Closer look at mounted motor and wheel

A look at the mounted motor and wheels

                                                      

Wiring for motors

Closer look at the wiring

2/6/2012

Today in class we spent some of the beginning of class putting the final touches on our circuit boards so they would be in working order for programming.  We discussed the basics of using our breadboards and how they are used to test and prototype.  We also discussed the differences between "sourcing" and "sinking" and how each configuration can be used.  We used are circuit board along with a breadboard and a simple program in PICAXE to cause an LED to blink on and off.  Using the breadboard, we made a circuit using a resistor and LED then wired it to our circuit board for power and the micro controller for instructions.  While we were writing the program, we learned some of the words used in PICAXE such as high, low, pause and symbol.  We wired this circuit to demonstrate both sourcing and sinking.  The last item we talked about in class was servo motors and Pulse Width Modulation (PWM).

 

In the above picture a connection is made to the circuit board from the laptop from the three pin connector on the board, through the modified DB9 cable, which connects to a USB adapter and finally into the laptop.  Power is supplied by the 9.6 volt battery.

The video above shows the result of the first program we wrote for our circuit boards.  The LED turns on for two seconds then turns off for two seconds.  This will repeat until power is turned off to the board.

2/1/2012

Today we continued our work on our circuit boards.  I finished adding the final components to the board.  After I finished soldering on the last pieces, I wove two pieces of blue wire through four holes, which had to be drilled bigger, and soldered one to the power terminal and the other to the diode at the bottom of the board.  I also set the chips in their sockets, a Uln2003 darlington array, a L293NE driver and a Picaxe 40x2 micro controller.  Next I soldered the toggle switch to the end of the blue wires, then put heat shrink over those solder joints.  Next I began to work on DB9 programming cable.  For our purposes we only need the 2, 3 and 5 pins.  I stripped the grey outer insulator and then the insulators of each individual wire.  I placed a piece solder in the number 2 socket then used the mulimeter to see which wire went to socket 2.  I did the same thing for the number 3 and 5 sockets.  After I had the correct wires I placed crimp sockets on each wire, so they can be connected to the 1x3 connector on our circuit board.  They female end of the DB 9 cable will be plugged into a USB adapter then plugged into our laptops so we can program our circuit boards.  After I finished the cable I assembled part of the robots body.

Underside view of soldered blue wires

Blue wires woven into holes in board

Toggle switch

Top view of chips in place

     

Crimps on wires leading to the 2, 3 and 5 sockets

Stripped DB 9 cable

         

Side view of robot body

Top view of robot body