DEWBOT VI

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Whirling Dervish - spinning about wheelbase center - we hold on to the ball
DEWBOT VI is designed to meet the specific challenges of the 2010 FRC game, BREAKAWAY. This robot combines a novel, award-winning multi-mode, 4-wheel pivot drive-train with a powerful kicker. The drive-train provides outstanding maneuverability and traction. Its multi-mode operation is flexible and keeps the opposition guessing. This is a brand-new drive-train design for 1640. A technology we've been developing since June.

The kicker is powered by latex tubing tension "springs" and is capable of kicking the ball entirely across the field. The kicker foot's 15 inch width makes ball centering a low-precision operation; the ball's trajectory is independent of which point of the kicker foot makes contact with the ball. While the immediate kicking force is provided by tensioned latex tubing, pneumatic cylinders are used to tension (cock), latch and fire the kicker.

We kept DEWBOT's profile low, so that it could drive through the tunnels. We wanted to be able to clear any balls that came to rest inside the tunnels.

DEWBOT also goes over the bumps quickly and safely. While the bump face angle is 45°, a long wheelbase and 4 wheel drive keep the robot's tilt angle to less than 28° during a bump traverse. Inventor was used to analyze the frame clearance (between front and rear wheels) needed to clear the bump and this clearance was precisely provided. The robot's Center-of-Mass is kept low (9.75" from grade) and centered between the 4 wheels. As a result, DEWBOT VI has never tipped during a bump crossing (so far).

In designing and building DEWBOT VI, we continued to follow and expand upon old good practices:

  • The robot was designed by engineering calculation. Old drive-train models were updated and improved. New models were created to understand how pivot drive needed to work and how to control it. These models were extensively used.
  • The robot was designed using CAD (in the form of Autodesk Inventor and AutoCAD). The degree of CAD pre-design was very high. A very, very few pieces were modeled in CAD after being built.
  • The CAD Model was used as the basis for the Bill-of-Materials and also used to directly guide procurement.
  • We used a great many forms and jigs. Building forms and jigs to facilitate accurate and reproducible fabrication of robot parts has become a part of the team's culture.
  • We did a lot of welding. The quality of our welding has advanced from okay to pretty darned good (both a design and welding improvement). Also, we are capable of welding on the fly. Welding has passed from being a special operation to a normal practice. Only one weld (noncritical) failed in DEWBOT VI during the two Regional competitions.
  • Our bumpers can be changed in less than a minute. This year, all of the connection point are designed and symmetric. Last year's Rizzo design was retained, with improvements.
  • The Battery box is thermo-formed polycarbonate. It allows easy and fast battery change. Maintenance has become first-of-mind.
  • An action plan was posted for each build night.
  • A Punch-list was maintained (daily) during the final portion of the build season.
Team on Shipping Night

We also initiated some new practices:

  • Through good planning and execution, we were able to deliver a mechanically and electrically complete chassis to programming at the middle of week 4. We've never done this before.
  • We built a proxy chassis to allow parallel development of the kicker and possessor mechanisms without interfering with the programming team's access to the chassis. Thia was a phenomenal time-management tool during the build season, but turned out to be a life-saver when we needed to improve the possessor between Finger Lakes and Drexel.
  • Integration - The newly-formed Design Team took charge of integrating and coordinating the efforts of different build teams (with middling results).
  • We did our first vacuum-forming of Polycarbonate.
  • We utilized a sponsor, Wamac Inc., to machine parts requiring a precision beyond our capabilities. We provided dxf files of critical parts, making this our first true CAD/CAM experience.
  • We did a great job recruiting students and mentors.

Accomplishments:

Team Sab-BOT-age after receiving the Creativity Award sponsored by Xerox
  • 1640 received the (BR)2 Engineering Excellence Award.
  • We received the Largest Toolbox in the House Award at Duel on the Delaware for our extraordinarily large screwdriver.


Breakaway Game Information

The game for 2010 is Breakaway soccer with a twist, there are two 12" tall humps that traverse the field. There are also two goals at each end rather than one. Oh and robots, did we mention that there would be six robots?

Detailed documentation about the game:

Complete Manual for Breakaway
Breakaway documentation page - you can get individual sections here
Breakaway game animation

DEWBOT VI Build

The build season lasts 45 days, starting with a cold January morning and ending up in the middle of an even colder February night. The chronicles of the DEWBOT VI Build season make interesting reading of how we all band together to perform an almost impossible task of designing, building and testing a robot in such a short time frame. Associated with each weeks build are pictures showing happy (and towards the end, tired) roboteers and mentors hard at work.

Design Details

The links below will take you to details about the robot components.
Pivot Assembly

CAD Design

Drive Train

DEWBOT VI utilizes an award-winning multi-mode, 4-wheel pivot drive-train. Each wheel is independently driven and steered. If we do this well (from both a mechanical and programming perspective), we have an extraordinarily maneuverable robot and one well-suited to 2010's BREAKAWAY competition. Pivot Drive was selected for:
  • Its superior maneuverability. DEWBOT VI has true 2d maneuverability combined with the ability to align soccer balls with the goal.
  • Safety while crossing the bump. A 6wd robot would tilt over further during the climb and would also experience two tipping points. The second of these (coming off the flat top of the bump) will put the robot at a considerable tipping risk unless center of mass (CoM) is very low.
DEWBOT VI is able to safely cross the bump and also drive through the tunnel. For both of these actions, the robot will need to drive in its long (x) axis direction. Chassis orientation is important for us in BREAKAWAY.
Drive Train Team Page

Mechanical / Scoring

DEWBOT VI’s scoring strategy is focused on scoring soccer balls. Towards this, we should be able to:
  • Herd up to 3 soccer balls and push these into the goal if playing in the alliance zone
  • Herd balls with the robot side as well and also push into the goal using the side.
  • Kick the ball towards the goal. We expect to be able to reliably score from Mid-field and to at least be able to reliably move balls from the opposing zone to the alliance zone with a single kick over both bumps. Bonus if we can reliably score from the opposing zone.
  • Clear soccer balls from the tunnels
DEWBOT VI has a Kicker capable of kicking cross-field. The robot also has a centering possessor with a dual-roller design which avoids ball entrapment under the chassis. Side guards keep balls from getting under the chassis from the robot's sides.
DEWBOT VI has no provisions to Elevate or Suspend.
Mechanical Team Page

Tactical

Our basic strategy is to score goals. We thought from the start that the extra point for hanging wasn't worth it. In that 20 second period we can score three goals. The extra weight, complexity, and the possibility of the rack being full or being blocked by an alliance member wasn't worth the effort.
Detailed Tactics can be found on the DEWBOT VI Tactical page with student information on the Competition Team Page.

Electrical

This years wiring supports a number of different elements.

  • Drive Train - as discussed above the drive train is driven by 8 motors. On each pivot is a drive motor and a steering motor. Magnetic sensors track the steering position of each pivot
  • Gyrocompass - keeps track of the overall direction of the robot in relationship to the field. Even though the robot will twist and spin, it knows what direction the goal is in.
  • Camera - we us a web camera to find and zero in on the goal. Above the goal is a black and white bulls eye target. The programming uses the input from the camera and gyrocompass to aim and fire at the target.
  • IR Sensors - there are two IR sensors mounted at the front of the robot. These sensors can track the soccer ball from 5 feet away. This allows us to move up and "capture" the ball with our possessor.
  • Possessor - is a sticky cylinder rotating at high speed. When it goes in one direction the ball is drawn to the robot (we are putting "back-spin on the ball". In the other direction it gives the ball a gentle kick towards the goal. The direction and speed of the possessor is controlled by the cRio control computer.

The electrical page has details of the build season. Read all about the activities and see the details of the wiring.

Electrical Team Page is the discussion page on current activities and to do items (it may or may not be empty

Pneumatics

DEWBOT VI - as designed in Autodesk Inventor (23-Oct-2010)
DEWBOT VI uses pneumatics to cock the Kicker and to release (fire) it.
The robot has an on-board compressor and (4) Clippard compressed air storage cylinders.
There are (3) solenoids: one to cock the Kicker (pushing back the Kicker thereby tensioning the elastic "springs"), the second to latch the Kicker in or release the Kicker from this tensioned ("armed") state and the third to raise and lower the lower possessor bar.
The cocking cylinder is a 2" bore x 4" stroke Bimba cylinder. It also has a 1.25" bore "helper" on the same air circuit.
The latching cylinder is 3/4" bore x 1/2" stroke.
The possessor lower bar cylinders are (2) 3/4" bore x 4" stroke.
Recycled SMC SY3000 series solenoids are used. These have a Cv = 0.30, meeting the 2010 requirements.

Programming

Programming for this years robot is more complex than any other year. While there are two modes, an autonomous mode where the robot drives itself and a teleop mode where roboteers drive the robot, there is a huge amount of shared programming.
The largest amount of programming is used to manage the drive train. As chronicled above we have a pivot drive. Each pivot has it's own drive motor to move the robot. By varying the speed of each wheel the robot direction can be changed. If you make the right side drive motors go faster than the left the robot moves in a gentle arc to the left.
The pivots also turn 360 degrees. Each pivot has it's own steering motor and a magnetic sensor. The sensor tells us what "direction" the pivot wheel is turning. So if we want to move to the left, we rotate the wheels 90 degrees to the left and apply power and the robot moves, looking like a crab. This is motion is call strafing, allowing us to quickly move side to side across the field.
The wheels can turn at any angle, allowing the robot to go in any direction. This crab like motion allows us to get to the ball while keeping the front kicker towards the goal. We strafe or crab over, align and kick.
On the fly we can change modes to "snake mode." This allows the robot to act like a snake going after prey. In our case the ball is the prey, snake mode keeps the ball in front of the robot (snake) while the back of the robot moves around. This allows us to herd balls into the goal.
Since the wheels can turn 360 degrees the robot can spin around on it's axis allowing us to reorient directions quickly.
Finally while there is a "front" on DEWBOT VI where the kicker is, as far as the drive system is concerned there is no front. If you rotate the robot 90 degrees to the right, what was the left side is now the front.
So it's like rubbing your stomach while patting your head while chewing gum while running!
The DEWBOT VI Programming page has more details about the programming, the Programming Team Page has details about the week to week activities.

Weight

DEWBOT weighed in at 112.2 lbs at shipping. without the bumpers or the battery. The max weight is 120 lbs so we are comfortably under. Our only design change to mitigate weight was reducing the robot's polycarbonate cover thickness from 3/16" to 1/16", saving about 5.5 lb.
Between the Finger Lakes and Philadelphia Regionals, the team revisited the possessor and built a working version. This was installed at the start of the Philadelphia Regional, increasing the robot weight to 115.8 lb.
The bumpers weigh 12.6 lb per set (there are two sets, red & blue), also well under the 20 lb maximum.
Robot Center-of-Mass (with bumpers & battery installed) corresponds to the Center-of-Wheelbase (17.5" from rear edge of chassis frame) and 9.75" above the playing field. This isn't just good, it's great.
The Design Team maintained a very nearly real-time Bill-of-Materials (used for parts procurement throughout the design/build process and used this as a tool to manage robot mass during the design process. The Bill-of-Material was used for: 1) managing parts procurement; 2) monitoring and allocating mass; and 3) monitoring and allocating cost. The team also monitored Center-of-Mass closely.

Bumpers

One of the key element in the robot construction is the bumpers. They are a key safety feature of the robot since there is a reasonable amount of inter-robot contact. (And they say the NFL is tough). The bumpers have stringent size requirements, but the most important feature is that they go on and off the robot quickly. Rizzo created and fabricated an elegant but simple system in 2009. He refined it in 2010 to the system that we are using.
Detailed drawings can be found on the Bumpers Page.

Events

Second Bay at DEC
Downingtown Area Robotics expanded into a 2nd bay at DEC. The new bay will be used for FRC and VEX storage. The original (larger) bay will house our power tools and will remain a work area.
Pancake Breakfast - 6-December-2009
Downingtown Area Robotics All-you-can-eat Pancake Breakfast at Exton Applebee's was a great success. Both the 8 AM and 9AM seatings were almost full. We had great service from our robotic waitstaff (students not robots). Applebee's donated the full cost of the food. With the gift basket raffle we collected over $1000. Everyone had a great time and we look forward to doing it next year!

Finger Lakes Regional

The team's performance was disappointing, with 2 wins, 7 losses and 1 tie (0-0). We placed 37 out of 44 in the qualifying matches and were not selected for an Alliance.
The poor performance was attributed to control software problems, lack of an effective possessor, and shortage of practice. We developed an aggressive and focused action plan to address the first two of these prior to the Philadelphia Competition.

Philadelphia Regional

Our best Regional Competition ever! We placed 17 of 44 in the qualifying matches (with 6 wins and 3 losses). We we selected to compete with the 5th Alliance (selected by 639(Code Red) & 87(Diablo)). We made it to the semifinals, where we were eliminated by 341(Miss Daisy), 365(MOE) and 486(Positronic Panthers), who went on to win the competition.
Team 1640 Sab-BOT-age played consistently well throughout the competition. We were a strong scorer from either the middle or near field, and managed a goal from the far field as well. With great agility & traction, we played phenomenal defense when we needed to. We crossed bumps easily and went through the tunnel without issue.
Team Sab-BOT-age and DEWBOT VI received the Xerox Creativity Award for it's innovative 4-wheel independent pivot drive-train.

PARC XIII

1640 placed 8th seed out of 19 teams and was selected by Team 2753 (Team Overdrive) for the 3rd Alliance (together with Team 339). We defeated the 6th alliance in two games in the Quarter-Finals, but were ourselves defeated by the 1st Alliance (Teams 25, 341 & ) in the Semi-Finals.
Team 1640 received the Gracious Professionalism Award.
DEWBOT VI was plagued by mechanical problems at PARC XIII, missing a qualifying match in the process.

Monty Madness

Sab-BOT-age made a strong showing against a very competitive field.
We finished qualifying matches as 10th seed out of 42 teams.
We were the first selection of team 365 (MOE), captain of the 6th alliance. Team 2344 (Saunders Droid Factory) completed our alliance. Alas, we were defeated in the quarterfinals by the 4th alliance (103, 341 and 75).

Bridgewater-Raritan Battle Royale

DEWBOT VI participated in the 2nd Bridgewater-Raritan Battle Royale (BR)². Team 1640 received the competition's Engineering Excellence Award for DEWBOT's unique, multi-mode pivot drive-train and the mirror mounted to find balls hidden behind the bumps. 1640 placed 12th out of 21 teams in the qualifying matches and was selected by the 2nd Alliance (2753 Overdrive & 1279 Cold Fusion). We were eliminated in the semifinals.
There was also a large VEX event--the first VEX Round-Up Qualifier in the world--held concurrently at this location. 18 teams participated and Team 81 brought home the Build Award.

Indiana Robotics Invitational

For the first time, Team Sab-BOT-age participated in the Indiana Robotics Invitational hosted by Lawrence North High Scool in Indainapolis. We performed well at this event, learned things, had fun (didn't get hurt) and hope to return again next year with an even better robot. More information concerning scouting and problems encountered is a available, as is a trip photo gallery.

Team Picnic at Warwick Park

1-August at the Warwick Park, 2-dusk. FRC Medallions and Team Certificates were presented to the 2010 team members and new members had the opportunity to meet everyone.
Who's afraid of a little rain? It rained for just a little while and the temperature was mild.
Great food. Great company. Great conversation. Some horseplay as well.

Duel on the Delaware

16-October-2010. Sab-BOT-age's 4th time participating at Duel on the Delaware. First "official" FRC competition for 5 new students. All new FRC students had the opportunity to participate as Human Players.
We finished 10th out of 28 teams in the qualifying matches. Team 007, the 8th alliance captain, invited us and team 433 (Firebirds) to join their alliance. Alas, we did not make it to the semi-finals.
The Team Screwdriver won an award.

Car Wash

17-October-2010. We washed cars the Chick-fil-A in Lionville, raising over $400.

FRC Pancake Breakfast

23-Oct-2010. Our 2nd annual All-you-can-eat Pancake Breakfast at Applebee's in Exton. Special guest appearance of Capt'n Rizzo & company. Over $1,500 raised!

Ramp Riot

Placed 21st out of 36 in the qualifying matches. We were selected as a partner for the 5th alliance, comprising Teams 303 (Panther Robotics), 522 (Robowizards) and ourselves. Alas we lost a Pivot in the first playoff match and were unable to repair this before the 2nd match in which our alliance was eliminated.
We had to deal with several other mechanical problems during the match.
This was a first competition for several students and mentors.

Spare Parts

We will be taking spare parts with us to the events. We are taking five boxes:

Red or Purple - Safety equipment / display parts / Judges information
Blue - Electrical / Computer / Pneumatics
Black - Mechanical
Silver - Tools
Clear or Red - Battery (robot and tools)

Detailed lists can be found on the DEWBOT VI Travel Supplies page.

Website

This year is the first year for our wiki website. We've spent almost a year of calendar time with over 2000 hours of effort to upload over 1900 pictures and documents and create over 200 pages of content with an additional 100 pages of system related information. Everything about our robot team and our robots can be found here.

Outreach

Our robotic outreach programs are described in our news pages. We have done events for the Regional FLL, Girl Scout Girls in Gear, and the Girls Exploring Tomorrow's Technology (GETT) program.

Sugartown Lego Expo

Downingtown Area Robotics FRC, VEX and FLL Teams all participated in the Sugartown Elementary School's Lego Expo and Robotics Fair on the evening of 16 April 2010. Team 1640 (especially Siri Maley) assisted Sugartown Elementary in setting up its FLL program in 2008.

Downingtown Science Fair

Downingtown Area Robotics FRC, VEX and FLL Teams all participated in the Downingtown Science Fair at Lionville Elementary School on the evening of 3 May 2010.

S.T.E.M Defined!

Downingtown Area Robotics provided a robotics demonstration for all ages at DASD's S.T.E.M. Defined night at Downingtown Middle School, 19 May 2010. Our room was packed with both robots and humans! FLL, VEX and FRC robots were all present and busy. DEWBOT VI faced off against DEWBOT V while DEWBOT III watched the door. Thanks to all the Roboteers, Mentors and Parents whose hard work made this is great success.

Upper Uwchlan Block Party

Downingtown Area Robotics FRC & VEX Teams entertained & educated kids and adults alike at the block party on 19 June 2010.

Presetation & Demonstration at FIATECH

Carly, Sasha & Kenneth at FIATECH
Kenneth, Sasha and Carly of Team 1640 presented and demonstrated DEWBOT VI to FIATECH during their annual meeting on 5-Oct at the Sofitel, Philadelphia. The three presenters did a great job and generated a great deal of interest. Thanks also to Matt and Nicole for their assistance at the event.
About FIATECH: FIATECH is a consortium of industries and companies from the industrial, power, and retail markets that, of necessity, build large assets such as refineries, power plants, large commercial buildings, or manufacturing facilities. In addition, it includes the leading providers of engineering, design, and construction services...
We thank our long-term sponsor, Bentley, for the gracious invitation to make this presentation.

Franklin Institute Robot Conflict Demonstration - 9-Oct-2010

FRC Team 1640 (Sab-BOT-age) was invited to demonstrate DEWBOT VI at Northeast Robot Club's (NERC) Franklin Institute Robot Conflict. DEWBOT wisely stayed out of the arena. FTC Team 3489 (Minds in Gear) also represented FIRST at this combat event.

Processes

We formalized some processes during the Philadelphia Regional. Immediately following each competition, we held a brief Pit Meeting during which the Drive Team, Scouts, Videographer and pit crew review the competition and highlighted any problems. Repairs, modifications and changes in tactics were discussed and agreed upon. A Pit action plan was developed and executed.

In addition, standard pit actions were posted as a Pit Checklist. Checklist items were executed following each competition.

Our end-of-FRC-season Post-Mortem Analysis is available.

Programs

Details of our robotics program can be found on the Team 1640 Mission and Program page. Our DEWBOT VI Elevator Speech is something we get everyone to learn, you never know when you will run into a potential roboteer or sponsor.

Team 1640 2010 Summer Program kicks off on Wednesday, 16-June. During this meeting, we'll set our summer objectives.

Sub-Teams

FRC Team 1640
Steering Committee
Design Team Page
Drive Train Team Page
Mechanical Team Page
Programming Team Page
Electrical Team Page
Media Team Page
Game Elements & Carpentry Team Page
Competition Team Page

People

There are a large number of people that were involved with the success of DEWBOT V from students to mentors but especially our sponsors.

DEWBOT VI Students
DEWBOT VI Mentors
Sponsors 2010

See our other robots in the Robot Archives.