Summary of Data Collection For period of 27 May 2011 to 25 August 2011 Daniel Leow

Contents Introduction and scope Data collection setup Data summary by bus type Analysis and findings Data summary by axes Analysis and findings Conclusion Daniel Leow

Introduction and Scope Daniel Leow

Introduction and scope Data captured in this stage of the research is to profile the bus motion for each bus type. The profiling of the motion is to determined whether there are differences in bus motion among the three types of the buses. Data captured are; X axis – Lateral motion where negative indicate left motion; positive indicate right motion. Y axis – Longitudinal motion where negative indicate braking/deceleration; positive indicate acceleration. Z axis – Vertical motion where negative indicate down motion; positive indicate up motion. Daniel Leow

Introduction and scope The three types of buses in Malaysia Single Deck Low Floor (Metropolitan bus) Single Deck High Floor (Express bus) Double Deck (Express bus) Daniel Leow

Introduction and scope Data captured are; X axis – Lateral motion where negative indicate left motion; positive indicate right motion. Y axis – Longitudinal motion where negative indicate braking/deceleration; positive indicate acceleration. Z axis – Vertical motion where negative indicate down motion; positive indicate up motion. Daniel Leow

Data Collection Setup Daniel Leow

Data Collection Setup Basic hardware and software setup USB GPS receiver (SiRF Star III) Macbook Laptop with built-in accelerometer Figure 1: Basic Setup Daniel Leow

Data Collection Setup (cont.) Position: Equipment mainly placed on a flat surface in the bus to ensure that the accelerometer sensors are directly in contact with the bus. Figure 2: Equipment in the bus Figure 3: Equipment in the bus Daniel Leow

Data Collection Setup (cont.) Calibration: accelerometer is calibrated to zero point of the raw output values from the sensors Figure 4: SeisMaCalibrate Daniel Leow

Data Collection Setup (cont.) Data: Captured using SeisMac, raw data stored in CSV file format. Figure 5: SeisMac Daniel Leow

Data Summary Daniel Leow

Summary of Data collection by sessions Table 1: Data Collection Daniel Leow

Data Summary by Bus Type Daniel Leow

Data Summary Double Deck – Graph 1 (lateral and longitudinal) Daniel Leow

Data Summary Double Deck – Graph 2 (vertical and velocity) Daniel Leow

Data Analysis Double Deck As shown in Graph 1, the lateral force is significantly relative to longitudinal force. As you can see the low and the high spikes are very much at the same frequency. In Graph 2, the vertical force are relative to the velocity of the vehicle. As you can see that there are higher spikes when the vehicle speed are higher Daniel Leow

Data Summary Single Deck Low Floor – Graph 3 (lateral and longitudinal) Daniel Leow

Data Summary Single Deck Low Floor – Graph 4 (vertical and velocity) Daniel Leow

Data Analysis Single Deck Low Floor As shown in Graph 3, the lateral force is not significantly relative to longitudinal force. The spikes in the longitudinal forces are fairly consistent mainly because there are frequent stops. In Graph 4, the vertical force are relative to the velocity of the vehicle. As you can see that there are higher spikes when the vehicle speed are higher. Daniel Leow

Data Summary Single Deck High Floor – Graph 5 (lateral and longitudinal) Daniel Leow

Data Summary Single Deck High Floor – Graph 6 (vertical and velocity) Daniel Leow

Data Analysis Single Deck High Floor As shown in Graph 5, the lateral force is significantly relative to longitudinal force. The spikes in the longitudinal forces are fairly consistent mainly because there are frequent stops. In Graph 6, the vertical force are relative to the velocity of the vehicle. Daniel Leow

Data Summary by Axis Daniel Leow

Data Summary Lateral Force (X axis) – Graph 7 Daniel Leow

Data Analysis Lateral Force (X axis) There are higher lateral force for Single Deck Low Floor bus compared to the other two types of the buses. This would have been expected because the buses taking many turns in the metropolitan roads compared to the express bus usually travels on straight road. Followed by the Single Deck High Floor bus and the Double Deck bus has the least lateral force motion. Daniel Leow

Data Summary Longitudinal Force (Y axis) – Graph 8 Daniel Leow

Data Analysis Longitudinal Force (Y axis) There are higher longitudinal force for Single Deck Low Floor bus compared to the other two types of the buses. This would have been expected because the buses have to take frequent stops in the metropolitan roads compared to the express bus usually stops once or twice in the entire journey. Followed by the Single Deck High Floor bus and the Double Deck bus has the least lateral force motion. Daniel Leow

Data Summary Vertical Force (Z axis) – Graph 9 Daniel Leow

Data Analysis Longitudinal Force (Y axis) Double Deck and Single Deck Low Floor bus shows fairly consistent readings. Single Deck High Floor bus shows inconsistent in data reading mainly because the sensor also picks up the vibration from the bus engine. Daniel Leow

Conclusion Daniel Leow

Conclusion The lateral and longitudinal force are significantly relative to each other especially for Double Deck and Single Deck High Floor bus. However, this is not much significant for Single Deck Low Floor bus. Nevertheless, Single Deck Low Floor bus showed higher readings for both lateral (Graph 7) and longitudinal (Graph 8) force. For lateral force, it reached 0.6g. The other two types of buses only reached 0.4g. As for the vertical force, it is significantly relative to velocity especially for Double Deck and Single Deck High Floor bus. However, this is not much significant for Single Deck Low Floor bus. As such, the setting of equipment for driver notification alert can be determined from this findings. Daniel Leow