# Bump Switch System for WunderBot II By: Matt Barley.

## Presentation on theme: "Bump Switch System for WunderBot II By: Matt Barley."— Presentation transcript:

Bump Switch System for WunderBot II By: Matt Barley

Detailed Subsystem Specifications: Physical Design 2”x4”x21” Bracket attached to bottom of WunderBot II Platform with additional 2”x4”x4” block supports to stabalize bumpers Bumpers constructed from PVC piping attached to brackets via 5/8” all- thread, washers, nuts, and springs between front stabalizing blocks and PVC

Detailed Subsystem Specifications: Original Design The front bump switch system contains two tactile switches (right, left) The rear bump switch system has one tactile switch All three are input into a Combinational Logic Circuit

Detailed Subsystem Specifications The onboard PC is notified of a collision and also of what bumper is in impact via a 3-bit BCD number from the interfaced micro- controller.

Detailed Subsystem Specifications: Circuit Design Input Variables: X  Rear Bump Switch Input Y  Front Right Bump Switch Input Z  Front Left Bump Switch Input

Detailed Subsystem Specifications: Circuit Design Output Variables: A  Collision Indicator B  Third digit of Binary Coded Decimal C  Second digit of Binary Coded Decimal D  First digit of Binary Coded Decimal

Detailed Subsystem Specifications: Circuit Design BCD  Bumper Binary Representation 1  Front Left001 2  Front Right010 3  Both Front Left &011 Right 4  Rear100 * Assume impact will not occur from front and rear bumpers simultaneously

Detailed Subsystem Specifications: Circuit Design Truth Table: X Y Z | A B C D | Minterms 0 0 0 | 0 0 0 0 | m 0 0 0 1 | 1 0 0 1 | m 1 0 1 0 | 1 0 1 0 | m 2 0 1 1 | 1 0 1 1 | m 3 1 0 0 | 1 1 0 0 | m 4 1 0 1 | X X X X | m 5 1 1 0 | X X X X | m 6 1 1 1 | X X X X | m 7 * Notice inputs X, Y, Z are the same as outputs B, C, D

Detailed Subsystem Specifications: Circuit Design Simplified Map for Variable A: A = X + Y + Z 111 1XXX X Z Y

Detailed Subsystem Specifications: Circuit Design Simplified Map for Variable B: B = X 1XXX

Detailed Subsystem Specifications: Circuit Design Simplified Map for Variable C: C = Y 11 XXX

Detailed Subsystem Specifications: Circuit Design Simplified Map for Variable D: D = Z 11 XXX

Detailed Subsystem Specifications: Circuit Design 5.0 V A B C D XY (X + Y)Z

Detailed Subsystem Specifications: Revised Design Very difficult to position tactile switches with physical bumper design; working sufficiently without damaging the switches Replaced tactile switches with IR sensors

Detailed Subsystem Specifications: Revised Design Revised physical bump switch system with IR Sensors in position Sensors activated by movement in wood blocks attached to bumpers’ bolts underneath the WunderBot II Platform