Evergreen Valley High School EVHS Robotics – The Prototypes

Today we did the following:

• Finished assembling the rollers

• Finally mounted the encoders

• Cut all the plastic to size

• Re-soldered and re-wired everything….again

• Ran into a problem with the left motor, but it was just a connection problem

• Started working on the driver station, and decided on a 2 layer station

• Mounted the second level of electronics (the bridge, and 2 jaguars)

• Made all the wires neater with zip ties

• Figured out a way to mount the slope so that the orbit balls will come up better

• Mounted the Fisher Price motor for the front roller, along with a sprocket, chain, bearings…

• Bought bright, neon orange spray paint for our team number on the bumpers

• Mounted two more triangular plates on the frame

Summary for Friday (2/13) workday:

• Worked on rollers more

• Figured out that the ABS was going to be too big to just screw onto the PVC, so slivers of the ABS were cut from the piping and then fitted onto the PVC.

• We were able to cut the conveyor belting into strips and mounted most of them onto the rollers

• All the ordered materials arrived: encoder mount, extra round tubing, and the conveyor belting

• Replaced the wires and crimps on the electronics board (crimps kept falling out, and some of the jaguar wires weren’t the correct size)

• The battery mount was screwed onto the frame

• Mounted two more triangular plates on the frame for support

• We were photographed by our school’s yearbook team

We managed to finish 1 and a half of these rollers, but we need a total of 3.

We were running short on time, so we decided to meet after school on Wednesday, and did the following:

• Started to make rollers
• Cut metal pieces/bars to mount the rollers onto the superstructure

At today’s meeting we finally started to build our robot’s superstructure, and among other things:

• Finished bumpers

• Cut, sanded, pounded, measured, center-punched the metal pieces supporting the basic frame

• Cut 3 inches off the wooden board holding the electrical components to make space for the ramp

• Asked about plastic for sides of the robot (~$100 for a 4′ x 8′ piece)

Starting work on the superstructure……

A picture of the robot at the end of the workday.

We had a short after-school meeting on Wednesday February 4th, and accomplished the following:

• Wired up the signal/diagnostic light.
• Attempted to install the accelerometer, gyro, and encoders, but we didn’t have a soldering gun at the time.
• We also prepared the angles and wood boards for mounting the bumpers.

The bumpers are almost ready to be mounted onto our robot.

Hard at work…modeling and programming.

Brian and Jeffrey working on the wood board bumper mounts.

Here’s an update of what we did at NASA on Saturday 1/31/09:

• We got the camera up and running, and it now tracks the pink and green trailer colors

• Finished the prototype

• Changed the design by adding in a few more rollers and decreased the angle of the slope

• Had a successful test of the roller and shooter.

• Cut the all the needed bumpers at the right angle

• Cut and sanded all the L-brackets for the bumpers

• Drilled the holes for the L-bracket pin

Measuring out the bumper length…

We tested out the camera’s color tracking abilities.

Assembling the hopper.

Screw fail! :

Today we:

• Finished the prototype’s wooden frame, except for the conveyor belt because we did not have enough surgical tubing

• Attached the trailer hitch to the robot

• Tested the robot with the trailer attached, consequently, turning the robot became much more difficult

• Found that going backwards while attached to the trailer will be a challenge

Our second trip to NASA…

More prototype brainstorming…

We tested out or robot with the full trailer attached, and found out that its turning ability was……less than satisfactory…

Things we accomplished at today’s meeting:

• Built a wooden frame of the proposed design

• Fixed both ToughBoxes, and found the solution of gluing in gear pins

• Uploaded pictures and did some blogging

• Programming team tested out various codes/commands

• Figured out a method of connecting the surgical tubing

• Bought 4 more Orbit Balls

All wired up!

Taking apart a board to use the wood for a prototype.

A fallen comrade.

Sanding down parts to use for the wooden prototype.

This meeting, most of our team went to a workshop at NASA, where we had more tools and resources to build our robot. We accomplished the following:

• Solved the problem with the ToughBox (a few of the gears had to be flipped over in order to be flush with one of the sides)

• Changed the chassis to a short and wide design

• Cut the frame and make it so that the middle would have a space for the orbit ball

• Solved the chain alignment problem with a new chain, added a few new gears, and washers

• Attached chains from two motors to all four wheels

• Cut and secured the wooden base to mount the electronics/control system

• The code has been modified to work with two separate joysticks. One for each of the two motors, thus enabling a “tank drive” option

• Wrote in the ability to slowly speed up the robot even if you throttle the control stick all the way forward or backwards.

James and Mr. Kuo working on putting together the new short and wide frame.

The completed base frame.

We also were able to look at past robots and acquire some ideas for our design. A few options we had in mind were:

• Have a rotating bar in the front to collect the balls, a conveyor belt the balls up to a holding space at the top of the robot and either

• Shoot the balls out like a tennis ball shooter

• Use a “hopper” idea where we dump all the balls into the trailer

• Use gravity to have the balls slide down and into the trailer

• Use some sort of pneumatics pump to push the balls out (might be too slow/not enough force to do this idea though)

Saturday January 10, 2009

We got the control system all setup, and we had a successful “smoke test”, and got the wireless router and gaming bridge set up with the driver station.

The base has been nearly completed, all 4 wheels have been installed, along with 2 of the 4 chains.

After the base was completed, we duct taped a sheet of masonite onto the frame just so we could mount and test out the electronics and software.

Based on the obviously poor performance of the robot, we came up with a different design.

Jeffrey modeling with the almost completed base.