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- Ivarsson, Maria, 1977-
(författare)
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Fuel Optimal Powertrain Control for Heavy Trucks Utilizing Look Ahead
- 2009
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The road topography in highways affects the powertrain control of a heavy truck substantially since the engine power is low in relation to the vehicle weight. In large road gradients constant speed is not possible to keep, which would have been beneficial otherwise, and in some uphills shifting gears becomes inevitable. If information about the road ahead, i.e. look ahead information, is available, then the powertrain can be controlled in a more fuel efficient way. Trial runs are performed, where the velocity trajectory that minimizes energy consumption, is calculated and communicated in real time as set points to the conventional cruise control. This look ahead control gives significant fuel consumption reductions compared to a standard cruise control, while keeping to the same mean speed. The results are the inspiration to further studies in how powertrain control can benefit from look ahead information. An engine with a non-linear fuel map is studied to understand its impact on fuel optimal speed. It is shown that for a significant fuel map non-linearity, quantified by a threshold value, constant speed in small road gradients is no longer optimal. Further, an automated manual transmission (AMT) optimal gear control is studied. It is shown that the reduced propulsion of a typical AMT gear-shifting process must be considered when choosing when to shift gears. Thus, additional reductions of fuel consumption are obtained with a look ahead control based on knowledge of engine and transmission characteristics.
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| 2. |
- Agrell, Fredrik, et al.
(författare)
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Control of HCCI During Engine Transients by aid of Variable Valve Timings Through the use of Model Based Non-Linear Compensation
- 2005
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Ingår i: SAE transactions. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0096-736X. ; 114:3, s. 296-310
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Tidskriftsartikel (refereegranskat)abstract
- One of the main challenges with the Homogeneous Charge Compression Ignition, HCCI, combustion system is to control the Start Of Combustion, SOC, for varying load and external conditions. A method to achieve this on a cycle-by-cycle basis is to vary the valve timing based on a feedback signal from the SOC of previous cycles. The control can be achieved with two basic valve-timing strategies named the Overlap- and the IVC-method. The Overlap-method works by trapping of residuals while the IVC-method affects the effective compression ratio. In an earlier paper it has been shown that if the two methods are incorporated into one controller, SOC can be controlled in a relatively large operating window although the transient performance was not sufficient. The reason is that the simple PI-controller cannot be made fast enough to cope with the transients without magnifying the cycle-to-cycle variations of the combustion into instability. In this work a model based control system that features a non-linear compensation, based on the inverse of the non-linear function from valve timings to ignition delay, is suggested and evaluated. The results show good transient performance. Control performance from engine tests is reported. A combined engine and control simulation system is used for the development of the control strategies. The simulations are accomplished with a commercial cycle simulation code linked with a commercial control simulation code. The simulations are iteratively verified against engine test data. Engine tests are conducted on a single cylinder engine equipped with a hydraulic valve system.
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| 6. |
- Agrell, Fredrik, et al.
(författare)
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Transient Control of HCCI Through Combined Intake and Exhaust Valve Actuation
- 2003
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Konferensbidrag (refereegranskat)abstract
- Homogeneous Charge Compression Ignition, HCCI, has the attractive feature of low particulate emission and low Nitrogen Oxides, NOx, emission combined with high efficiency. The principle is a combination of an Otto and a Diesel engine in that a premixed charge is ignited by the compression heat.
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| 7. |
- Bagchi, Satyajit, et al.
(författare)
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Application of ZUPT-Aided INS to Indoor Localization of Tightening Tools
- 2018
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Ingår i: Procedia Manufacturing. - : Elsevier B.V.. - 2351-9789. ; , s. 565-569
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Konferensbidrag (refereegranskat)abstract
- This paper presents the application of zero velocity detectors in the field of indoor positioning for industrial tightening tools particularly in tandem with an extended Kalman filter to achieve reliable estimates in position. Inertial measurement units are promising devices to use in positioning systems. Data has been collected from IMU while moving in a predefined trajectory on a tightening test rig and post-processed in MATLAB using the implemented algorithms and the results are presented. They indicate that the error accumulation can be effectively controlled to 25 cm/min for the commercial grade IMU and 15 cm/min for the navigation grade IMU.
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| 8. |
- Carlqvist, Per, et al.
(författare)
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Benchmark of High Level Programming : Pilot Case Vibration Control
- 2009
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Ingår i: Proceedings of the 9th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2009. - 9780955308260 ; , s. 361-364
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Konferensbidrag (refereegranskat)abstract
- The advancement of technology of laser pattern generators needs to meet demands of the rapid product development pace in the display and semiconductor markets. A hypothesis is that efficiency in the development process of complex systems can be improved by introducing a higher level programming approach. This will make a model and simulation based development (MBD) strategy more easy to adapt leading to 1) higher technical performance at shorter development time from idea to product introduction phase, 2) lower cost of goods, 3) shorter production-, installations- & upgrade time and 4) possibility of very efficient field support & service, etc. The success of an MBD approach is dependent on the simulation software capability to express the behavior of a real system. Consequently, as a first step towards an MBD approach, the investigation covers a pilot-study where results from simulations are compared to an existing controlled system.
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| 9. |
- Devesse, Wim, et al.
(författare)
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A real-time optimal control method for swing-free tower crane motions
- 2013
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Ingår i: Automation Science and Engineering (CASE), 2013 IEEE International Conference on. - : IEEE. - 9781479915156 ; , s. 336-341
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Konferensbidrag (refereegranskat)abstract
- Tower cranes are commonly used at construction sites all over the world. These cranes are prone to swinging of the cable suspended payload, resulting in unwanted payload oscillations that have severe effects on the safety on the site as well as on operational speed and accuracy of the payload delivery. The nonlinear nature of the rotating crane motion makes controlling these oscillations a complex task. In this paper, a time-optimal velocity control method is developed to enable fast and swing-free tower crane movements by applying Pontryagin's maximum principle on a set of decoupled payload pendulum equations. The controller is developed in a feedback form and is implementable in real-time. The performance of the controller is compared with other control methods such as notch filtering and input shaping. Simulations using a detailed tower crane model show that time-optimal swing-free movements can be obtained and payload vibrations are reduced to levels lower than those that can be achieved with the other control methods, while resulting in significantly faster rise times in slew velocity.
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