Friday 11/28/08

Attendance: Ian, Kevin, Penelope

Agenda:

• Continue to work on the arm
  

What happened:

We cut a C channel to be slightly smaller for the second segment of the arm. This peice has two free-spining wheels on the end to easily use the ramp, and will have servos controling a bucket-like mechanism on top of it. We mounted a motor at the end of the first arm to controll the second one, however we didn't have any real control over it. We decided to gear it down, all we needed to do was come up with something small with a good gear ratio; what we ended up building is a little gearbox that works at a 4:1 ratio, this used two more small gears and two of the medium gears.

Today we had to do a lot of build, find out it doesnt quite fit, tear appart, rebuild slightly differently, etc. We remounted that motor 3-4 times and still have to mount a second support for the second arm. There was some difficulty when we were trying to work and found we were missing one of the peices we needed to connect anything to a motor shaft, also at the end we accidentaly broke one of the power tabs off of the motor so now we have to replace it.

The current position of the motor controller is a problem, we need to move it to allow all the motor wires to reach regardless of the arm's position. We discussed trying to use the prototype sensor board to both control a large number of buttons and run some fancy lights for things like turn signals, brake lights, etc. We now need to wait for new parts to arrive before we can really continue, and we have to move the compass sensor to make room for the second arm segment.

Monday 11/24/08

Attendance: Ian, Kevin

Agenda:

• Build a manipulator
• Tweak drive train

We modified the drive train because there was a short length of C channel that was sticking out the back of the robot, which would catch on the ground when we tried to go up the ramp. We used two peices end to end to replace the old peice and fix that problem.

For a manipulator we wanted something that could: collect pucks, score in the central triangle, pick pucks up off the ground, and lower the ramp so we could drive up it. So far we have mounted a motor, and created a large arm that is the base of the bin. We need to cut one of the plates to hold another motor mount, yet give space for a better range of motion. Our intent is to mount a similar mechanism on top of what we have with servos controling a bucket like thing at the end of that one.

National Science Teacher's Convention 11/22/08

Attendance: Ian, Chris, Nolan, Kyler, Kevin

Agenda:

• Work on the robots
• Demonstrate the FTC robotics system
• Work on software

We were invited to show our robots in the area that FIRST had at the convention.  Those of us from team 267 worked on their manipulator, while kevin and I made a lot of progress on our program.  It now recognizes if both buttons on the front or back are being pushed and can respond appropiatly, we also worked out a couple of bugs in the compass functions which left the robot unresponsive because it didnt have enough power to turn the last couple of degrees; the motor power in that function is scaled based on how far the robot has to turn so the closer it is to the target heading, the slower it goes to prevent it from overshooting.

Ian McBride

Meeting Friday 11/21/08

Attendance: Ian, team 267

Agenda:

• Finish mounting sensors
• Debug color sensor
• Work on program

I mounted the rig that had been built at the previous meeting to have two touch sensors on the front of our robot.  I also mounted the touch sensor multiplexor.  We realized that we werent getting good readings from the color sensor, so we tried to bring it closer to the ground.  It works more reliably after lowering it about a quarter of an inch.  I modified the code a little to test the light sensor more easily and to have it constantly display the color it sees; the gray tiles show up as 0, the white tape should show up as 1 or 11-13, the red tape is around 9, and the blue tape should be more like 3 or 4.  This way we can find distinct values for all the possible starting locations and use it to find the lines on the feild. 

If the robot sees a color immediatly then it knows its on the platform, and which alliance it is on.  If it doesn't then it knows it is in one of the squares on the feild, and when it goes forward it will find out what alliance it is on by reading the colored tape box.  This is important because it means that we can write one program that will do the appropriate thing in all four starting cases, because the feild is diagnaly symetric.

Meeting Tuesday 11/18/08

Attendance: Kevin, Ethan, Penelope, Jared, Nick, Nolan, Tucker

Agenda:

• Calibrate Ramp
  
• Discuss Strategy
  
• Continue Autonomous Code
  
• Manipulator Arm
  

What happened:

Ethan taught Jared how to start the blog entry. Nolan and Nick are calibrating the ramp. Kevin is working on the autonomous code. Tucker and Penelope are working on the manipulator arm.

After calibrating the ramp we tested it out on the robot and we first thought that the robots front was jamming in the ground while still on the ramp then we found out that that was the back of the robot so there are no problems besides giving it another arm to press the ramp back down and return to its starting position.

• I saw that the robot couldn’t get up the ramp because the push sensors on the back were running-a-ground and stopped the robot from getting up the ramp. I suggested that he goes up the ramp backwards and it worked.

Jared

• I came up with a theory that the thing at the end of the dump mechanism could also serve as a pickup-type thing. It scoops up pucks off the ground and puts them in the dump truck.

Penelope

• I worked on the autonomous code. It now goes forward until it sees white and then continues forward for a set number of rotations then makes a left turn. The big improvements are that we can now read the color sensor and that the turn functions work.

Kevin

Meeting Wednesday 11/12/08

Attendance: Ian Mcbride, Kevin Burns, Ethan Dedrickson


Agenda:

• Talk
• Work on ramp
• work on navigation program
• weigh pucks
• measure hinged board panel and figure out screw placement
  

What Happened:

• I worked with John on the measuring of the starting panel. we measured one inch in from each side to find the correct placement of the 'X' wooden board stand. After discovering that the panel could not fit because of the placement of the other screws, we moved it around until it woul fit well. when there was a perfect spot for it, we measured about 4" in from the ends to find the placement of the screws. We didn't have the screws with us, but the drilling spots are marked.
  
• Ian discovered the weight of the pucks in grams, which was 1.962 oz
  
• Ian and Kevin worked on programming.
  
• Jeff showed me two examples of motor design. one put more stress on the gears, and the other was much more efficient by splitting the weight.
  
• Kevin worked on a design that would bring in and hold the touch sensors to they were at least 6" apart. The wheels are 10" apart.
  
• We all made a big mistake in that you acnnot plug in touch-cables through metal ]=. The design for the touch sensors was built wrong so the cables could not plug in correctly.

-Ethan Dedrickson

• I massed one puck and found it had a mass of 55.6 grams.
  
• I worked with kevin on programming some basic autonomous functions
  
• we worked on writing code to go forward until we see a line and code to use the motor encoder

-Ian McBride

• I worked with Ian on the navigation code and on a better mount for the touch senors, as mentioned above it did not work.
  
• I was able to determine that the pucks wiegh 1.96oz. 

-Kevin Burns

Team,

I just received the pucks via UPS. I have eighteen for our two teams.

Eight pucks weigh exactly one pound, according to my scale.

John