Minibot Deployment Analysis

20 Jan 2011, Siri

How Do We Get There?Alignment Routes

Direct

Hit Wall

Swing Around

Routes also apply to same-side tower

Overshoot

Route ComparisonRoute Length Ease In Lane? Orientation

Hit Wall(also skim inside)

2 4? Yes Close Fit Long

Overshoot 3 3? Possible Either

Direct 4 3? No Either

Swing Around 1 1 Yes Either

Point: We’re not going to get this right on the fly.Auto-alignmentDriver feedback

Skills

• Speed• Crab• Snake• Running into things

Difficulties

• Little Time• Poor Visual• Possible Overshooting• Unknown Start Position/Config

Features

• Doesn’t require LoS• Let’s us run into things

• Fast orientation to correct side (e.g. locks on correct side in spin)

• Robust• Easy to Implement

CasesDirect Approach

+ Ease of implementation+ Robust- Requires some pre-alignment- Hard to lock on in a spin

Indirect Approach

+ Very little driver alignment+ Fast+ Locks on in a spin- Harder to implement-Less Robust?Going to happen.

Need to Redirect force

vector

Indirect CaseNeeds/Desires/Wishes

Inside• Shall have opening =30” [N], >35” [D], >45” [W]• Shall slope (linear or non-) inward [D]• Shall shape to base as much as necessary for deployment accuracy [N]• Shall not interfere with deploying or racing Minibot [N]

Outside• Shall direct funnel opening around tower [D]• Shall NOT misdirect robot along outside within last 5” [N], 10” [D], entire length [W]• Shall not interfere with deploying or racing Minibot [N]• Shall not exceed robot frame width when stowed (27”) [N]

Concept – Curved U(Hybot 7-work1)

Self-guides around base

(Robot won’t be able to strafe in this position back up) Aligns without hitting guides

Concept – Curved U Stored(Hypot 7-work)

Tower

Concept – Inverted Funnel

Best Case for auto alignment

Current Issue: SpaceApprox 50” wideFolded form stretches min 21”

Minibot Deployment

Features• FAST!!• Never Misses• Fast!• Low weight & volume• Fast!

Thoughts• Fast pneumatics• Consistent guides

Less-Known Rules• Minibot can never exceed 12” cube• Hostbot can enter base plane at any time

Deployment ActuationState Zero (Stored)Aligned: NoOn Post: NoReleased: No

State Final (Deployed)Aligned: YesOn Post: Yes

Released: Yes

Interim States

Aligning StateAligned: Progress

On Post: NoReleased: No

Our Specs require Aligning before Deploying.Aligning requires moving Release must be false.

Deploying StateAligned: Yes

On Post: ProgressReleased: ??

Hostbot doesn’t move in Deployment Release can be simultaneous

Conclusion: 3 properties (2 conditions each), at least 2 must occur separately 2 or 3 actuations

Deploying vs ReleasingThese can happen simultaneously, but doing it with a single driven

actuator requires some thought…

Example:

Minibot

Box Latch is in front of Minibot in z-axis

Minibot

Pneumatic cylinder opens latch, kicks down wall/guiderails, and pushes out Minibot

Next Steps

• Test funnel shapes/bending• Finalize U hinge & supports• Prototype Minibots– Define deployment specs– If rails: how to “lock” on Post – If not: come up with something