Development and Validation of a Remote-Controlled Test Platform for Bicycle Dynamics

Through the electrification of bicycles, the implementation of new active and passive safety systems becomes possible. Examples for such systems are bicycle ABS, TU Delft - Fall Prevention Bicycle, Bosch Help Connect (eCall System for bicycles), airbag helmets and many others. One of the main difficulties in developing and testing such safety systems is, that test riders should not be exposed to high risks when testing early prototypes. Thus, an automated or remote-controlled test platform for the analysis of bicycle dynamics and for testing of newly developed safety systems could boost the development of such systems and make it safer. The main difficulty when developing such a test platform, which has been addressed in this work, is stabilizing it at low speeds (1.5 m/s - 4.5 m/s) and being capable of tracking a desired yaw rate, only using a steer actuator. In the following, the development of such a test platform is described and first experimental results are presented

Evaluation of the Driving Performance and User Acceptance of a Predictive Eco-Driving Assistance System for Electric Vehicles

In this work, a predictive eco-driving assistance system (pEDAS) with the goal to assist drivers in improving their driving style and thereby reducing the energy consumption in battery electric vehicles while enhancing the driving safety and comfort is introduced and evaluated. pEDAS in this work is equipped with two model predictive controllers (MPCs), namely reference-tracking MPC and car-following MPC, that use the information from onboard sensors, signal phase and timing (SPaT) messages from traffic light infrastructure, and geographical information of the driving route to compute an energy-optimal driving speed. An optimal speed suggestion and informative advice are indicated to the driver using a visual feedback. pEDAS provides continuous feedback and encourages the drivers to perform energy-efficient car-following while tracking a preceding vehicle, travel at safe speeds at turns and curved roads, drive at energy-optimal speed determined using dynamic programming in freeway scenarios, and travel with a green-wave optimal speed to cross the signalized intersections at a green phase whenever possible. Furthermore, to evaluate the efficacy of the proposed pEDAS, user studies were conducted with 41 participants on a dynamic driving simulator. The objective analysis revealed that the drivers achieved mean energy savings up to 10%, reduced the speed limit violations, and avoided unnecessary stops at signalized intersections by using pEDAS. Finally, the user acceptance of the proposed pEDAS was evaluated using the Technology Acceptance Model (TAM) and Theory of Planned Behavior (TPB). The results showed an overall positive attitude of users and that the perceived usefulness and perceived behavioral control were found to be the significant factors in influencing the behavioral intention to use pEDAS.Comment: Submitted to Transportation Research Part C: Emerging Technologies Journa

Introducing a pole concept for nodule growth in the thyroid gland: taller-than-wide shape, frequency, location and risk of malignancy of thyroid nodules in an area with iodine deficiency

Purpose : (i) To examine the criterion taller-than-wide (TTW) for the sonographic assessment of thyroid nodules in areas of iodine deficiency in terms of frequency, anatomical distribution within the thyroid gland and risk of malignancy. (ii) To develop a model for nodule growth in the thyroid gland. Methods: German multicenter study consisting of two parts. In the prospective part, thyroid nodules were sonographically measured in all three dimensions, location within the thyroid gland and contact to a protrusion-like formation (horn) in the dorsal position of thyroid gland was noted. In addition, further sonographic features such as the composition, echogenity, margins and calcifications were investigated. All nodules from the prospective part were assessed for malignancy as part of clinical routine at the decision of the treating physician adhering to institutionally based algorithms. In the retrospective part, only nodules with fine needle aspiration and/or histology were included. The risk of malignancy in TTW nodules was determined by correlating them with cyotological and histological results. Results: Prospective part: out of 441 consecutively evaluated thyroid nodules, 6 were found to be malignant (1.4%, 95% CI 0.6–2.7%). Among the 74 TTW nodules (17%), 1 was malignant (1%, 95% CI 0–4%). TTW nodules were more often located in the dorsal half of the thyroid than non-TTW nodules (factor 2.3, p = 0.01, 95% CI 2.1–2.5) and more often located in close proximity to a horn than non-TTW nodules (factor 3.0, p = 0.01, 95% CI 2.4–3.8). Retrospective part: out of 1315 histologically and/or cytologically confirmed thyroid nodules, 163 TTW nodules were retrieved and retrospectively analyzed. A TTW nodule was 1.7 times more often benign when it was dorsal (95% CI 1.1–2.5) and 2.5 times more often benign when it was associated with a horn (95% CI 1.2–5.3). The overall probability of malignancy for TTW nodules was 38% (95% CI 30–46%) in this highly preselected patient group. Conclusion: TTW nodules are common in iodine deficient areas. They are often located in the dorsal half of the thyroid gland and are frequently associated with a dorsal protrusion-like formation (horn) of the thyroid. Obviously, the shape of benign nodules follows distinct anatomical preconditions within the thyroid gland. The frequency of TTW nodules and their predominant benignity can be explained by a pole concept of goiter growth. The difference between the low malignancy risk of TTW nodules found on a prospective basis and the high risk found retrospectively may be the result of a positive preselection in the latter

Development and Validation of a Remote-Controlled Test Platform for Bicycle Dynamics

Through the electrification of bicycles, the implementation of new active and passive safety systems becomes possible. Examples for such systems are bicycle ABS, TU Delft - Fall Prevention Bicycle, Bosch Help Connect (eCall System for bicycles), airbag helmets and many others. One of the main difficulties in developing and testing such safety systems is, that test riders should not be exposed to high risks when testing early prototypes. Thus, an automated or remote-controlled test platform for the analysis of bicycle dynamics and for testing of newly developed safety systems could boost the development of such systems and make it safer. The main difficulty when developing such a test platform, which has been addressed in this work, is stabilizing it at low speeds (1.5 m/s - 4.5 m/s) and being capable of tracking a desired yaw rate, only using a steer actuator. In the following, the development of such a test platform is described and first experimental results are presented

Development and Validation of a Remote-Controlled Test Platform for Bicycle Dynamics

Through the electrification of bicycles, the implementation of new active and passive safety systems becomes possible. Examples for such systems are bicycle ABS, TU Delft - Fall Prevention Bicycle, Bosch Help Connect (eCall System for bicycles), airbag helmets and many others. One of the main difficulties in developing and testing such safety systems is, that test riders should not be exposed to high risks when testing early prototypes. Thus, an automated or remote-controlled test platform for the analysis of bicycle dynamics and for testing of newly developed safety systems could boost the development of such systems and make it safer. The main difficulty when developing such a test platform, which has been addressed in this work, is stabilizing it at low speeds (1.5 m/s - 4.5 m/s) and being capable of tracking a desired yaw rate, only using a steer actuator. In the following, the development of such a test platform is described and first experimental results are presented

Obtaining a Stabilizing Prediction Horizon in Quadratic Programming Model Predictive Control

In this paper, it is shown how a performance tuple can be obtained in model predictive control if the optimal control problem is a quadratic program. The quotient of the finite-horizon optimal cost and the tuple's first entry upper bounds the sum of all instances over the finite-horizon optimal cost. The tuple's second entry is a stabilizing prediction horizon. The algorithm taking the describing matrices and giving a performance tuple is easily verifiable

Effectiveness of Actuating on Rectilinear Bicycle Braking Dynamics

The aim of this study is to quantize the effectiveness of actuating on bicycle braking dynamics with focus on critical rectilinear maneuvers, namely wheel-lock and nose-over. Those situations define the physical limits of rectilinear bicycle braking. The objective is to gain a profound understanding of the limits of unactuated vehicle dynamics by creating a multibody model that is parametrized and validated via an instrumented bicycle. A good model accuracy is obtained modeling the rider as a point mass located at the experimentally determined center of gravity and using tire slip curves which are also gained by experiment. In the second step the obtained system knowledge is used to evaluate possible ways of actuation, which on the one hand could assist the rider not to leave the limits of braking dynamics and on the other hand extend them. Researched types of actuation are brake torque modulation, suspension fork locking as well as active manipulation of the riders center of gravity by a seatpost actuator

Efficacy of an internet-based self-management intervention for depression or dysthymia – a study protocol of an RCT using an active control condition

Abstract Background The treatment of major depressive disorder, a highly prevalent disorder associated with pronounced burden, is a large challenge to healthcare systems worldwide. Internet based self-management interventions seem to be a cost effective way to complement the treatment of depressed patients, but the accumulating evidence is mainly based on the comparison to waitlist controls and treatment as usual, which might lead to an overestimation of effects. Furthermore, studies assessing long-term effects and possible negative outcomes are still rare. Methods/Design The proposed study evaluates the efficacy of the German version of the iFightDepression® tool in comparison to an active control condition. A total of 360 patients with mild to moderate depressive symptoms are included into a two-armed randomized controlled trial. They receive one of two six week interventions; either the iFightDepression® tool or progressive muscle relaxation serving as the control condition. Both intervention groups receive information material, weekly tasks via the internet and regular phone calls as part of the intervention. The primary outcome is change in depressive symptoms after the intervention period, as measured with the Inventory of Depressive Symptomatology. Satisfaction with the program, usability, changes in perceived quality of life, and possible negative effects are assessed as secondary outcomes. Discussion This study represents the first randomized controlled trial on the iFightDepression® self-management tool in its German version, aiming at efficacy, but also at providing new insights into so far understudied aspects of E-mental health programs, namely the specificity of the treatment effect compared to an active control condition, it’s continuity over a time course of 12 months, and possible negative effects of these internet based interventions. Trial registration International trial-registration took place through the “international clinical trials registry platform” (WHO) with the secondary ID 080–15-09032015. German Clinical Trial Registration: DRKS00009323 (DRKS.de, registered on 25 February 2016)

Intralogistics application with a fleet of robots on a private 5G campus network

This paper presents the concept and the current state of implementation of a semi- autonomous robot fleet for logistics applications in a campus environment. The communication is realized via a private 5G SA network. The robot fleet performs its logistics tasks semi-autonomously on campus and can deliver mail or parcels, for example. Sensor data (GPS, camera images, 2D and 3D laser scanners, ...) is sent to a central computing unit in the control center via the 5G interface to analyze and store live data and influence the robot’s actions at real time to save costs of the robot and conserve energy to increase operating time. The operator in the control center can intervene in unusual situations at any time and remotely control the robots via 5G. The described system is being tested with a fixed private 5G SA network and a nomadic 5G SA network as public cellular networks are not performant enough in regards to low latency and upload bandwidth. The nomadic network approach opens up further application scenarios such as company premises or events. The system has so far been built and tested with one robot. The expansion of the robot fleet with different platforms is currently in progress