MSc Projects

Delft University of Technology 

Some brake systems have the annoying habit of making a very high pitched and loud noise while braking, which is called ‘brake squeal’. Such brake squeal is usually caused by friction induced vibration. Some seminal work on brake squeal in bicycle rim brakes has been done by Robin Walhout [1] and Jan Groenhuis [2]. We like to extend that work towards bicycle disk brakes.

Adaptive speed control
Modern e-bikes are equipped with a number of sensors which are able to measure: GPS location, forward speed, angular speed and linear acceleration of the rear frame, pedal torque support level, and the ambient temperature, at a sample rate of 2 seconds. These sensors open opportunities within the concept of IoT (Internet of Things) to have vehicle-to-vehicle and vehicle-to-infrastructure communication. This opens a whole set of new applications which can make cycling safer and more time efficient, like: collision prediction, early warning systems, adaptive speed control for green wave, or to enforce speed limits.

At the Royal Gazelle bicycle factory there is a vast amount of knowledge about the relation between bicycle geometry and handling. This knowledge is based on experience, and with this experience new bicycles are designed in an evolutionary manner. Academic research on bicycle dynamics and control (handling) has created theoretical knowledge on dynamics and control for bicycles [1,2]. There is a wish to make a connection between the two, by classifying geometry designs as used by Gazelle in a standard manner and relate them to the dynamical behavior as predicted by the recent theoretical bicycle models [2]. This could lead to a revolution in bicycle design.
 

The objective of the proposed MSc assignment is:
“To develop an optimal control strategy stabilizing the bicycle at low speed”
Address the following questions:
- How does the rider perceive this enhanced stability?
- Can you measure the change (decrease) in control effort from the rider?
- How does the stability enhancement influence the maneuverability?
- Is there a trade-off between stability, handling and maneuverability?

Behavior modeling of Vulnerable Road Users

Shimmy is a recurring problem in all of our strollers.
Mostly by trial and error we are able to keep shimmy under control under normal use, but the lack of a proper underlying theoretical model makes it hard to predict the behavior of new stroller designs, or even to know with which strollers we are near a ‘tipping point’ in dynamic behavior.

With the Whipple model of the uncontrolled bicycle now well established the question remains how do people control the mostly laterally unstable bicycle?  One promising direction is adding a minimal musculoskeletal rider model to the Whipple model. With this rider model one could drive and stabilize the bicycle.

Assignment: Add a minimal (few extra degrees of freedom) musculoskeletal model to the Whipple bicycle model and add a control strategy such that the bicycle is laterally stabilized  and driven by the pedal forces resulting from muscle forces. Investigate the robustness of the control by adding longitudinal and lateral perturbations (a hill and side wind). Think of a way to quantify the handling quality by f.i. looking at the control effort.
The candidate will start by studying the literature on bicycle dynamics, and musculoskeletal models. Next, the two models will be incorporated into one model. Various control strategies will be explored.
 

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Contrary to cars and motorcycles, little is known about bicycle tires. There is some knowledge on rolling resistance but an experimentally validated model for the lateral tire forces generated by the tire is unknown. Such a model is absolutely necessary to be able to predict the handling of bicycles in various extreme situations. Currently a bicycle tire testrig is under development (see picture) for testing tire characteristics on the large drum tire tester which is available in the TU Delft lab.

Assigment: Finish the design and construction of the bicycle tire testrig. Measure lateral tire characteristics (side force, alignment torque versus slip angle and camber angle) for a number of different bicycle tire-wheel combinations.  Develop a simplified bicycle tire model (like a brush model), determine the bicycle parameters from the tests and see how the rest of the measured data fits the model predictions.
 

Design, build, and test a bicycle handle bar with torque feedback which can be used as an input device for the simple bicycle desktop simulator.The candidate will start by studying the literature on bicycle dynamics, and driving simulators with haptic feedback. Next, design a haptic steer for torque input with torque feedback and finally test the device on various groups of bicycle riders (novice, experienced, elderly). 

Background
The Delft Bicycle Laboratory wishes to develop a bicycle simulator: a stationary bicycle on a moveable platform, driven by a computer model of a bicycle, on which one can sit, steer, lean and pedal. As a first step, a simple desktop bicycle simulator has been built. The input device is a joystick for forward speed and steer torque commands and the output device for feedback control is a simple 3D avatar of the bicycle on a computer screen. It turns out that even an experienced bicycle rider cannot stabilize the unstable bicycle at low speed (v< 4 m/s). It is conjectured that the human controller needs haptic torque feedback for proper control.

Bicycle Dynamics and Control
One of the great mysteries in bicycle dynamics and control is the question: “how do we stay on track”. In this project we wish to develop a controller model which, for a given forward speed, stabilizes the bicycle and keeps it within the bounds of the bike path at minimal control effort. 

Door de stijgende vraag naar onderwater pijpleidingen wordt er continu onderzoek gedaan naar het verbeteren van de mogelijkheden om deze leidingen op de zeebodem te kunnen leggen. De dynamica van de te leggen pijp, die vanaf een schip, door het zeewater op de zeebodem rust, speelt hierin een cruciale rol.

De focus van dit onderzoek is het analyseren van het dynamisch gedrag van de onderwater pijp. De pijp wordt door zijn omgeving beïnvloed: Tijdens het pijpenleggen is er een continu samenspel tussen de pijp, het water (de hydromechanica) en het schip wat gevolgen heeft voor het gedrag van de pijp.