e_KINETIC WALL – Transformation of Kinetic Architecture from Architectural Concept to Engineering Design

ABSTRACTBus stop shelters are traditionally static structures built to encourage public bus ridership by providing waiting passengers with a shelter from wind, snow, and rain at the scheduled stops along a bus route. Thus, these structures increase the comfort of waiting passengers’ experience. Bus stop shelters with open fronts are comfortable during favorable weather, but fail to maximize a waiting passenger’s protection from inclement weather. Single-opening bus stop shelters offer waiting passengers the best protection from inclement weather, but in favorable weather conditions the section of the shelter farthest from the opening can become hot and uncomfortable to stand in, discouraging use of the bus stop shelter. This dilemma highlights the limitations of static structures. This project, a collaboration between the School of Design and the Department of Electrical and Systems Engineering, proposes the use of intelligent kinetic architecture to re-design the walls of a single-opening bus stop shelter. The e_Kinetic wall team produced a works-like prototype of a bus shelter wall. A microcontroller algorithm uses environmental inputs to control the opening and closing of subsections of the walls, increasing airflow through the shelter during favorable weather conditions, and decreasing airflow during inclement weather to provide better shelter to waiting passengers. A ventilation analysis was performed using FloVent computational fluid dynamics software, which showed that implementing the e_Kinetic wall in single-opening bus stop shelters effectively improves thermal comfort indices such as LMA (Local Mean Age) and PMV (predicted mean vote).

AUTHORSVignesh Chandramouli SSE ’10

Tyrus Lloyd TCOM ’10Kevin Osagie EE’10Hersh Singh EE’ 10

ADVISORDr. Jorge Santiago (SSE)

ACKNOWLEDGEMENTSSpecial thanks to Dr. Santiago for all his support

DEMO TIMESThursday April 22, 2010

10:30 – 12:00 PM3:30 – 4:00 PM

SYSTEM OVERVIEW

Figure 1: System Diagram

Sensors

Microcontroller

Linear Actuator

Wall PanelLED Light System

Environmental Inputs

Rain

Wind Speed Wind Direction

Temperature

Other Inputs

Proximity

Panel Open/Close

Switch

e_KINETIC WALL PROTOTYPE This prototype is a real-world realization, designed

by our team, of a design concept by Design School graduate student Kimberly Nofal

The works-like prototype frame (shown in figure 3) is made entirely of 2x4 wooden studs and is designed to have a L x W x H of 38” x 36” x 7” in order to simulate approximately a fourth of a bus-stop side wall

The wall consists of 5 columns of panels, with one actuator per panel, which can extend the panel out by 15/16” in 3 seconds

The worm-drive type linear actuators (shown in figure 4) were selected primarily because of they require power only during operation and have a very high load bearing capability

Each actuator requires 12 V & 1.5 A for operation Plexi-glass panels were selected primarily for their

light weight and translucency for the purpose of this prototype

The design is scalable both vertically and horizontally – scaling vertically requires using taller studs and scaling horizontally requires the addition of an additional stud for each additional column of panels

RESULTSMODELING & TESTINGBased on design specs from design firm Belson Outdoors, we modeled a single-opening bus stop shelter with traditional

clear plastic panels as shown in Figure s 5 and 6 and then replaced the side wall of this traditional bus-stop shelter with our e_kinetic wall design to model a bus-stop with an embedded e_kinetic wall as shown in Figures 7 and 8

Both walls were subjected to the same FloVent testing, with the bus stop entrance set to be the primary exit point for the air. The traditional bus stop design was the benchmark for our testing

For the bus-stop shelter with the kinetic wall, we “opened” alternating panels in a checkerboard fashion and subjected the structure to weather conditions (temperature, wind speed) based on historical Philadelphia August month data as August has the highest average and peak temperatures

The primary purpose of the test was to verify that this design improves the thermal comfort indices LMA (Local Mean Age) & PMV (Predicted Mean Vote) within the shelter relative to a traditional single opening bus shelter

Additional tests were conducted to determine optimal panel “opening” configurations under the August weather conditions

CONTROL ALGORITHM

Figure 2: Software AlgorithmProgram in C, intended for a single HC11 microcontrollerBefore algorithm (figure 2) execution, the necessary

system variables are declared, interrupts set up, and various input method settings initialized

The program is set to run every 5 seconds, reading sensor input sequentially until an unfavorable condition is found, or until all inputs have been examined

LED subprogram activates the LEDs when sufficiently dark

Figure 3: Concept

Figure 4: Prototype

UNIVERSITY OF PENNSYLVANIA – DEPARTMENT OF ELECTRICAL & SYSTEMS ENGINEERING & SCHOOL OF DESIGN

Figures 5 & 6: Single Opening Bus Shelter Model 3D and side perspectives

Figures 7 & 8: Single Opening Bus Shelter with e_Kinetic Wall