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Our robot, RP1, is a 1-meter tall dynamically-balancing walking biped intended to be entered in the RoboCup Humanoid TeenSize soccer competition in Suzhou, China in July, 2008.
Links: RoboCup 2007 Rules | RoboCup 2008 Schedule
Functional Requirements
What must our robot do? In order that our robot be considered a success, we have identified several functional requirements which follow both from the !RoboCup requirements and from our goals as robotics researches. As such, our robot must:
- Dynamically Balance - RP1 must keep itself upright using a feedback system which actively modulates its actuators to react to its changing environment.
- Walk - RP1 must walk at a sustained pace of 0.25 - 0.5 m/s. Walking is defined as bipedal locomotion with no flight phase, with at least one foot in controlled contact with the ground at all times.
- Self-Right - In case of falls, RP1 must be able to self-right itself using its arms in a roughly biomimetic way.
- Localize Itself - RP1 must be able to localize itself within a soccer field, under the rules and assumptions given by !RoboCup rules.
- Play Soccer - RP1 must be capable of playing soccer -- this includes kicking, dribbling, blocking, and sideways movement.
Existential Requirements
What must our robot be? Due to external constraints, there are several important qualities that RP1 must demonstrate. Our robot must be:
- Inexpensive - RP1 must require less than $1e5 in total development cost. In addition, its marginal cost per additional unit must not exceed $2e4.
- Self-Contained - All of the energy, computation, and actuation of RP1 must be contained within its frame. Batteries, computers, and other components must be on-board. A wireless link for mission-level autonomy is acceptable.
- Robust - RP1 must be able to withstand common falls without damage to key components. Custom and costly parts, such as in-house PCBs and custom actuators, must be sufficiently rugged and adequately interfaced so as to minimize costly damage.
Specific Specifications
The following set of specifications and benchmarks have been set for specific subsystems to ensure that RP1 meets the requirements listed above.
- Bandwidth - The main communications bus must be able to support 32kbps per actuator. On a one-bus architecture, this corresponds to a 640kbps synchronous bandwidth.
We don't care about per-actuator fault-tolerance.
We care about:
- Simplicity
- Maintenance
- Assembly
Mechanical
Functional Specs
- Walking Speed
- Forward AND sideways walking
- Must be able to TURN in place, and turn while walking
Existential Specs
- Weight: Within Rule specs (proportional to height)
- Height: 1 meter or more
- Body proportions in compliance with rules: Proportional to height
- 6 DoF Legs (x2), 2-4 DoF Arms (x2)
- Well-protected actuators (designed to break last)
- Survive 1 foot drop w/o actuators or custom electronics breaking
- Has 1-2 camera(s) mounted in the head and hardware to service it
Electrical
Functional Specs
- Vision: Can see ball / field
- Robust / Survive 1 foot drop w/o custom electronics breaking
- Batteries on Board / Energy Capacity in compliance with rules
- All Computing on Board
Existential Specs
- Battery Voltage: 14.4V?
- Positive lock connectors
- COTS connectors for wire
- Minimize connector count
- Potted or conformal coated electronics
- An IMU
- COTS Wireless link to brain
- Shock-mounted electronics
Software
Functional Specs
- Daisy-Chainable comm protocol
- Brain programmable in a STANDARD language
- Brain: update 20-100Hz
- Autonomous control
- Localization
- Perception
- Behavioral control
- Dynamic control
- Interface with operator (task level directions)
Existential Specs
- Ethernet, USB, CAN, IEEE 1394
- Quake-style remote controlling
- Wireless link to brain (802.11)
- Language
- NOT Prolog, Scheme
- Good Ideas: HIGH level language
- Stereo Vision system
- 15-30 FPS Color vision (stereo?)
- Inertial Measurement
- Temperature / Voltage / Force / Current Measurement
- Any internal sensing is generally OK