A robot is an automatic mechanical device guided by a computer program or electronic circuitry. Robots are used to go where people can't or don't want to go, such as dangerous, expensive, or difficult environments like space or undersea. Engineers design and build robots by following a process that involves determining requirements, designing subsystems, integrating systems, testing iterations, and modifying designs until the robot can perform its intended functions. The design process focuses on understanding needs, generating concepts, planning, building, testing, and refining a robotic system.

2. What is a Robot?

3. What is a Robot?
• An automatic mechanical device
• Usually an electro-mechanical machine guided
by a computer program or electronic circuitry.

4. Why use Robots?
• To go where people can’t
– To dangerous, expensive, or difficult
– radioactive areas, undersea, space, combat
• To do things people can’t or don’t want to do
– monotonous jobs
• To go where no one has gone before.
– Exploring space, the ocean, volcanoes, glaciers
• To learn engineering
• To have fun!

5. How do we design & build a robot?
• Designing and building is engineering
• What are goals of engineering?
– To understand human needs or desires
– To design and build tools or technology to meet
those needs or desires
– To make life easier, more pleasant, & better
• Just as scientists use scientific methods,
engineers follow a design process

6. Design Process: Relationships
• Don’t start by grabbing parts & building
without thinking
• Start with who, what, when, where & how?
– Who is in charge? To whom do you report?
– Who will you work with as a team?
– What is the job? What is your part of it?
– When is the work due? When are deadlines?
– Where will you work?
– How will you document and verify your work?
– How will you deal with challenges that arise?

7. Design Process: Strategic Design
• What are the “rules of the game”?
– What are the ways to score points?
– How can we stop opponents from scoring points?
– What is the highest possible score?
– What is a reasonable score in a match?
– What are our backup plans if we start losing?
– What are the penalties if we break the rules?
Swept Away video

8. Design Process: Strategic Design
• What do we want the robot to do?
– What are all the possible robot tasks for scoring?
– What are all possible robot tasks to prevent
opponent scoring?
– Rank each task (1-10) on benefit toward winning
– Rank each task (1-10) on how difficult the task will
be to accomplish
– Calculate benefit to difficulty ratios for each task
– Discuss and determine which tasks will give best
odds of success at winning the game

9. Design Process: Mechanical Design
• What do we have to work with?
– What materials, supplies, tools, equipment, hardware,
software, building space and time do we have to work
with?
– How is the robot going to move, pick up objects,
score, avoid blocking by opponents?
• What are the limitations and parameters to work
within?
– What are the limits on size, power, number of parts,
software, trial runs, space and time?
– What are the penalties for exceeding limits or
breaking rules?

10. Design Process: Mechanical Design
• What are the subsystems?
– Structure = “skeleton” of the robot
• Chassis, screws, nuts, bolts, spacers, & other hardware
• Tools needed to assemble and disassemble the robot
• Concepts: center of gravity, support polygon, stability
– Motion = “muscles” of the robot
• Square shafts, gears, motors, servos
• Concepts: motors vs. servos, gear ratios, torque, speed

11. Design Process: Mechanical Design
• What are the subsystems?
– Power = “heart and blood” pumps electric current
• Battery pack, battery box, chargers, wires
• Concepts: excessively draining, voltage drop,
overcharging, trickle charge, heat
– Sensors = “eyes & ears” essential for autonomous
functioning
• Bumper switches, limit switch, IR sensors, light sensors
• Concepts: analog, digital, ADC, DAC

12. Design Process: Mechanical Design
• What are the subsystems?
– Control = radio link with a human operator
• 75 MHz transmitter & receiver, VEXnet joystick
• Concepts: frequency, FM, channels, crystals, RFI
– Logic = “brain” of the robot that coordinates flow
of information and power
• VEX microcontroller, jumpers
• Concepts: input/output, digital electronics, logic gates

13. Design Process: Mechanical Design
• What are the subsystems?
– Programming = “rules” that govern robot behavior
• RobotC language (a version of C)
• Concepts: programming languages, tokens, syntax,
comments, variables, loops, conditional statements,
debugging, interpreted vs. compiled programs

14. Design Process: System Integration
• How are subsystems integrated into a
complete working system?
– What comes first: structure, control, power?
– How do motion requirements affect structure and
power subsystems?
– How do weight & speed affect power and motion?
– How do sensors affect the control subsystem?
– How do we switch between operator control
mode and autonomous mode?

15. Design Iteration
Trial Run
Document results
(observe, measure, video)
Document changes
(in design notebooks)
Modify
(one change at a time)
Evaluate
(Decide needed changes)

16. Design Iteration
Trial Run
Document results
(observe, measure, video)
Document changes
(in design notebooks)
Modify
(one change at a time)
Evaluate
(Decide needed changes)

17. Design Iteration
Trial Run
Document results
(observe, measure, video)
Document changes
(in design notebooks)
Modify
(one change at a time)
Evaluate
(Decide needed changes)

18. Design Iteration
Trial Run
Document results
(observe, measure, video)
Document changes
(in design notebooks)
Modify
(one change at a time)
Evaluate
(Decide needed changes)
Play the game!
(compete in final match)
Design Review