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Three fully electric motorcycles were tested and analyzed for acceleration, braking, and regenerative coast-down deceleration. A Zero DSR, BMW C-Evolution, and a Harley-Davidson LiveWire underwent each of the following test series. The first test series consisted of accelerating the electric motorcycles from a stop. For the second test series, the motorcycles were decelerated by using three different brake applications: front and rear brake application, front-only brake application, and rear-only brake application. For the third test series, regenerative coast-down deceleration was tested at different ride mode configurations. Regenerative braking systems are designed to convert the vehicles’ kinetic energy into electrical potential energy during the vehicles’ coast-down phase, resulting in a moderate deceleration. In addition to testing the vehicles’ deceleration during its’ regenerative coast-down phase, brake light activation delay relative to throttle roll-off was analyzed.

PC-Crash is an accident reconstruction program that enables the user to analyze vehicle collision dynamics and trajectory models. This research paper presents the utilization of PC-Crash to analyze motorcycle slide-to-stop dynamics. For this study, existing motorcycle slide-to-stop data from SAE 2019-01-0426 will be simulated and analyzed in PC-Crash. The selected dataset consists of three motorcycles: a 2002 Kawasaki ZRX-1200R, a 2006 Yamaha YZF-R6, and a 2013 Ninja EX300. Six of the thirteen slide-to-stop tests collected by Fatzinger [1] were simulated and analyzed in PC-Crash. The motorcycle initial ground contact speeds range from 37-52 mph. Parameters such as vehicle weight, sliding friction factor, motorcycle sliding trajectory, and yaw trajectory will be accounted for in each PC-Crash simulation. All tests were simulated using a 2D and 3D motorcycle model in PC-Crash.

PC-Crash is an accident reconstruction program allowing the user to perform simulations with multibody objects that collide or interact with 3D vehicle mesh models. The multibody systems can be a pedestrian, a motorcycle, or a motorcycle with a rider. The multibody systems are comprised of individual rigid bodies connected by joints. The bodies can be of various size and stiffness along with varying coefficients of friction and restitution. Additionally, the joints can be tailored to define pivot types and range of motion. The current motorcycle models in PC-Crash are generic and do not resemble a sport bike type motorcycle. They are only globally scalable such that you cannot adjust length, width, or height independently. However, the user can adjust each body and/or joint individually as needed. A model was created that resembled a modern sport bike motorcycle. In addition, a multibody rider was mounted on the motorcycle in a typical sport bike riding position.

Many new vehicles come equipped with Advanced Driver Assistance Systems (ADAS) as standard or optional features. These technology packages frequently include Lane Departure Warning (LDW), an electronic system designed to alert the driver when the vehicle begins to depart from its lane. These systems identify lane boundaries using computer analysis of video captured by a forward-facing camera, typically mounted near the rear-view mirror. Some vehicles are also equipped with Lane Keeping Assist (LKA). Upon detecting an unintended lane departure, LKA will make electronic steering and/or braking control inputs to keep the vehicle in its original travel lane. Four vehicles equipped with LDW and LKA were tested: a 2019 Toyota Corolla, 2019 Honda Civic, 2020 Ford Explorer, and 2019 Chevrolet Tahoe. Tests were conducted on a straight, flat road with clear lane markings. Lane departures to the left and to the right were initiated by the test driver at 45 and 65 mph.

Tesla Motors vehicles utilize a regenerative braking system to increase mileage per charge. The system is designed to convert the vehicles’ kinetic energy during coast-down into electrical potential energy by using rotational wheel motion to charge the batteries, resulting in moderate deceleration. During this coast-down, the system will activate the brake lights to notify following vehicles of deceleration. The goals of this study were to analyze and quantify the regenerative braking behavior of the Tesla Model 3, S, and X, as well as the timing and activation criteria for the brake lights during the coast-down state. A total of seven Tesla vehicles (two Model 3, three Model S and two Model X) were tested in both Standard and Low regenerative braking modes. All three Tesla models exhibited similar three-phase behavior: an initial ramp-up phase, a steady-state phase, and a non-linear ramp-down phase at low road speeds. Phase 1 was less than one second in length.

The objective of this study was to analyze the validity of airbag control module data in semi-trailer rear underride collisions. These impacts involve unusual collision dynamics, including long crash pulses and minimal bumper engagement [1]. For this study, publicly available data from 16 semi-trailer underride guard crash tests performed by the Insurance Institute for Highway Safety (IIHS) were used to form conclusions about the accuracy of General Motors airbag control module (ACM) delta-V (ΔV) data in a semi-trailer rear underride scenario. These tests all utilized a 2009 or 2010 Chevrolet Malibu impacting a stationary 48’ or 53’ semi-trailer at a speed of 35 mph. Nine tests were fully overlapped collisions, six were 30% overlapped, and one was 50% overlapped [2]. The IIHS test vehicles were equipped with calibrated 10000 Hz accelerometer units. Event Data Recorder (EDR) data imaged post-accident from the test vehicles were compared to the reference IIHS data.

Vehicle manufacturers are beginning to improve existing autonomous emergency braking (AEB) algorithms by adding pedestrian identification and avoidance capability. The Insurance Institute for Highway Safety (IIHS) has performed tests on eleven such vehicles; data are publicly available and were analyzed for this study. The first objective of this study was to compare Forward Collision Warning (FCW) engagement distance to target, pedestrian automatic emergency braking (P-AEB) brake application time, and incidences of impact across different manufacturers. It was observed that there exists a wide variation in FCW and AEB performance across manufacturers. FCW engagement distance tended to increase with test speed. Time from FCW engagement to AEB engagement was usually less than one second, with some manufacturer-specific variation.

The goal of this study was to determine bicycle braking performance, while considering different brake designs and applications. Eight bicycles were used to perform brake-to-stop tests: two full suspension mountain bikes, two hybrid bikes, one beach cruiser, one BMX bike, one road bike, and one single speed bicycle. The standardized brake testing procedure consisted of rear only brake application and both front and rear brake application. In order to maintain brake application consistency, a single rider performed all series of the brake tests at the same location, within a designated brake zone on dry asphalt. The tests were performed at initial velocities of 11 to 21 mph. For each test, the rider accelerated to the test speed and, upon entering the brake zone, applied maximum braking effort while maintaining a natural upright position in order to minimize lean. The associated skid marks deposited from wheel lock-up were verified, measured, and documented onsite.

This research focuses on the use of Event Data Recorders (EDR) to assist in calculating speed loss or ΔV undergone by a motorcycle in a broadside type impact into a vehicle. If the struck vehicle has EDR data, this could be a useful tool in calculating motorcycle ΔV or corroborating motorcycle ΔV calculations from crush or other methodologies. Certain parameters critical to calculation of motorcycle ΔV must be considered, including the appropriate effective mass to use for the motorcycle/rider combination. This study used crash test data to determine a method of applying parameter values to accurately calculate motorcycle ΔV in a motorcycle-vehicle collision. In this study, three crash tests were performed in which a motorcycle with a dummy rider traveling in the range of 42 to 51 mph collided into the right front corner of a vehicle traveling between 5 and 16 mph.

There is extensive literature on motorcycle skid/brake to stop testing on a host of motorcycle types, rider experience, brake system configurations and the associated deceleration rates. Very little information exists on deceleration rates involved with over-braking the front wheel. The subject of this paper addresses the deceleration rates of sport bike type motorcycles during over-braking of the front wheel. Based on the physics of a two-wheeled vehicle like the motorcycle, once the front wheel is over-braked and becomes locked, the rider has very little time to recover from the skid and often times falls. Another over-braking scenario, especially on sport bike type motorcycles, is the possibility of the rear wheel lifting and pitching over the front wheel. During the initial phase of braking, weight transfer to the front wheel occurs creating a greater level of traction.

Electronic control units (ECU) from Kawasaki Ninja ZX-6R and ZX-10R motorcycles were tested in order to examine the capabilities and behavior of the event data recorders (EDR). All relevant hexadecimal data was downloaded from the ECU and translated using known and historically proven applications. The hexadecimal translations were then confirmed using data acquisition systems as well as the Kawasaki Diagnostic Software (KDS)1. Numerous tests were performed to establish the algorithms which cause the EDR to record data. Issues of sensor and power loss were analyzed and discussed. Additionally, data sets were studied that involved maximum deceleration from ABS brakes. Similarly, data sets that involved traction control intervention were studied and analyzed. It was determined that the EDR recording ‘trigger’ was caused by the activation of the tip-over sensor, which in turn shuts the engine off.

Various electronic control units from Kawasaki Ninja 300 motorcycles were tested in-situ in order to heuristically examine the capabilities and behavior of the event data recorders (EDR). The relevant hexadecimal data was downloaded from the ECU and translated using known and historically proven applications. The hexadecimal translations were then confirmed using data acquisition systems as well as the Kawasaki Diagnostic Software (KDS). Numerous tests were performed to establish the algorithms which cause the EDR to record data. It was determined that the EDR recording “trigger” was caused by the activation of the tip-over sensor, which in turn shuts the engine off. In addition, specific conditions must be met with regards to the rear wheel rotation prior to engine shut-down.

Six electronic needle-display speedometers from five different manufacturers were tested in order to determine the behavior of the gauges following a power interruption and impact. Subject motorcycles were accelerated to pre-determined speeds, at which point the speedometer wiring harness was disconnected. The observed results were that the dial indicator would move slightly up, down, or remain in place depending on the model of the speedometer. The observed change of indicated speed was within +/- 10 mph upon power loss. Additionally, the speedometers were subjected to impact testing to further analyze needle movement due to collision forces. Speedometers were attached to a linear drop rail apparatus instrumented with an accelerometer. A minimum acceleration due to impact which could cause needle movement was measured for each speedometer assembly.