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Angular acceleration of 0.034 rad/sec2 sounds about right for this application. I make the mistake of not considering the right acceleration time- just the 7.5 seconds, in fact the motors would accelerate, steady and decelerate in a trapezoidal fashion. This was very helpful.

We have an automotive swivel seat that turns from the initial seating position to the final position outside the vehicle (90 degree swivel in 15 seconds). We would like to calculate the torque required for rotating the seat along with the person. We have calculated the inertia of the movable...

Thanks for the reply Nidum. Detecting if the drive is behaving abnormally would be possible only if I use a current sensor to sense actuator-block. By actuator-block I mean that some part of the mechanism in the system has malfunctioned/stuck. In this case, the motor driver would see a sudden...

Hi JBA. I hope the photo above makes it clear to you where the swivel point of the dish exactly is. This is an eccentric rotation. I've marked in the photo where I would place the actuator and top-support assembly. The top-support assembly would be a prismatic mechanism with a rod moving inside...

Hi Oz. We did not manufacture these dishes, so I'm not too sure on the material although I could take a guess. These are not SS, probably silver and copper coating on glass. Price of PV unfortunately does not have major effect on CSP. These are just reflectors and have no photovoltaic...

I am currently re-fabricating solar concentrator dishes to allow for automatic tracking of the sun during the day and month. The industry term for these dishes is 'CSP' (Concentrated Solar Power). Task at hand: The CSP parabolic dishes are currently manually adjusted to the position of the sun...

Thank you for the reply. No this is not a critical application like aircraft systems. Although, if accelerometer did fail in my system, errors would accumulate over a period of few days and system positioning would become highly inaccurate. No safety issue though. The reason 2 cheap...

My question relates to the reliability of low-cost accelerometers (MMA7455,ADXL345 etc.) in commercial products with a expected life expectancy of 5 years or more. The tilt angle reading from the accelerometer will be used as a feedback parameter to orient a single-axis plate-reflector...

S2M implies surface mount? Then I'm thinking of using the 1N5408 as per the spec sheets. Yeah I see the smd diodes on top, numbers blackened out . Thanks for the tip. https://en.wikipedia.org/wiki/1N400x_general-purpose_diodes

Apologies for the late reply. The motor no longer works. Hopefully its because some passive component got burnt-up. 1 good thing that seems to have emerged is that I have come closer to understanding the inner workings of the linear actuator. Please find attached the pics with descriptions of...

Thanks for the replies. FYI I managed to only get hold of 130V clamping voltage varistors. Nothing in the range of 18V is available. So, I'm thinking of connecting series-opposing 15V zener diodes instead. Is that okay? CWatters- "If you are concerned about something stalling/blocking the...

Alternatives to varistors as overload protection at DC motor DC Motor here implies 12V linear actuator w/DC Motor that consumes 2.8A under loading condition. Pretty costly equipment. I'm using a L298N motor driver connected in parallel to run the linear actuator. The motor driver is run by a...

Linear actuator spec.: 400mm stroke, 6000N, 2 limit switches, 5mm/sec, 12V DC supply, BIBUS IP65 casing. One of the limit switches of my LA (Linear Actuator) seems to have burned out. This happened because I accidentally plugged the LA leads into the AC mains socket (my LA is rated to run at...

Hi all! I need to decide on the production philosophy of an SEV(small electric vehicle) as a final part of my thesis project. Up until now, I have designed the package layout and body and performed a FE analysis (topology optimization) to arrive at a reasonable body-in-white structure. I did a...

EURONCAP front crash test involves crashing a car moving at 64 kph onto a deformable barrier at 40% of the total vehicle width. According to the EURONCAP website, this is equivalent to two vehicles crashing into each other at 55 kph. How did they arrive at this figure? I presumed that the...

Thanku all.

In case of a topology optimization (optimal material distribution), how do FEM software superposition different loadcases to arrive at one final result?

I am curious as to how finite element analysis software(like Hypermesh) go about superposition of loadcases(applied on the same model). I constrain my vehicle body for 1.loadcase (say bending) with the standard SPC's and constrain my 2.loadcase(say torsion) with Inertia relief constraints...

Zoki: Specified power of motor is 93 kW. This apparrently is a AC motor, sorry for the wrong info. 93000/360V= 258 Amps. I get a feeling this a bit too much.

I'm a Automotive engineer and hence lack the electrical engineering expertise that you might expect. This is related to a doubt I have in calculating the final battery voltage for an electrical vehicle. This is just a calculation query. I have a module consisting of 12 individual Li-ion cells...

My build will be from time-to-time be posted in the Automotive engineering forums in Physics forums. I would love to document and share the information online but unfortunately my contract blocks me from doing so. Neverthess...you'll find me in the AE forum :). Last question: What is the...

I am planning to use the Panasonic NCR-18650 cylindrical cells for a BEV (Battery Electrical Vehicle). As it would be easier to buy ready-made modules, I have found a supplier selling a Li-ion pack that delivers 417 Wh(or in other words 11.6 Ah) at 36 V (something like what this guy uses...

Actually, not much more to give than the diagram I have attached. I was hoping for some insights into rear damper packaging, for example: 1.Is the rear damper placed before/after the lower A-arm? 2.How much laterally to the centre do I place the damper?

I am quite uncertain as to why the rear damper is inclined at a angle to the inside of the car. By doing so, does one ensure for rear wheel travel to be along a curved up/down path? i.e I am perplexed as most of the modern rear suspensions are multi-link and have their dampers inclined → This...

True mal4mac. Engineers do look down on the humanities. It is a pity.

I've noticed that a FEW of the electrical vehicles have no front grill. I am quite surprised that they do not have one, because the condenser of the AC unit needs to have heat taken away from it (in other words, the condenser needs a heat exchanger). So, in view of the fact that E-vehicles don't...

Thanks old jim. I have a simple question: Does the transfer of C.G DURING a crash pose any major disadvantage? It seems logical that when the C.g shifts during a crash in a direction where the passengers are sitting, then there is going to be blood. Am I correct? So,with this simple...

I think automotive engineers call weight reduction 'Topology optimization', although I haven't come across articles relating structure weight to vehicle handling yet. If I may say so, handling of an automobile has always been related to the roll centre height, am I correct? So,if I find a...

Inter'part' linking, very interesting approach to design. Will start using this in CATIA right away. Thanks.

I am in the design phase of a lightweight electric city vehicle with a capacity of 15kWh. I am at a stage where I am moving elements like Electric motors, tranmission, DC-DC converters, Inverters, Battery charger and battery pack in a CATIA software model. In-order to cater to the wide-range of...

Sorry,found it. http://en.wikipedia.org/wiki/Backbone_chassis#mediaviewer/File:Lotus_Elan_car_chassis.jpg http://en.wikipedia.org/wiki/Backbone_chassis#mediaviewer/File:Lotus_Elan_car_chassis.jpg

In regards to the Lotus Elan from 1962, my book H-point says that Colin Chapman used the prop shaft tunnel as ''backbone'' to the body structure. Can someone please elaborate on this? Does this mean that the structure of the prop shaft tunnel acted like a stiffener for the entire body...

In CATIA V5R19, when I switch to the side view, how do I measure just the horizontal distance between 2 points that are not exactly in the same horizontal plane? When I use the tool 'Measure distance between' , I get a inclined measurement line which is exactly what I do not want. How do I...

I am a novice reading about the 7 OSI layers. I am reading this because I am currently working with a bluetooth device which is used to send serial data from the bluetooth module to the laptop. Since bluetooth is in itself a protocol,much like the 802 protocols, where among the 7 OSI layers does...

I am thinking in terms of principle of functioning of a damper. When damping is very small,the resonant frequency is almost equal to the natural frequency of the system. Here, the system is split into 2 parts:high natural frequency of vibration,low natural frequency of vibration. So,in the odd...

The use of the word 'response' complicated things for me.Response is what here exactly? You classified response under low frequencies in your text.I'm thinking in terms of the body of the car 'responding' to vibrations.

'Slow-active suspensions realize small switching frequencies to control low-frequency body movements,such as roll pitch and lifting motions.Fully-active suspensions reach switching frequencies,like semi-active suspensions,greater than the natural eigen-frequencies of the vehicle.'- an excerpt...

What's the significance of the 1st point above?

The PIDrobust Toolbox contains the following functionalities und features: 1.capability to process plants with delay time 2.capability to support plant uncertainties 3.adjusting the controller parameters based on maximum robustness 4.adjusting the controller parameters in a interactiv editable...

Can someone explain what the PID robust methodology is all about in simple words?http://www.irt.rwth-aachen.de/en/fuer-studierende/downloads/pidrobust/ One of the advantages of the method stated is that "capability to process plants with delay time ". Whats so great about that? Usual...

No lisab,no lab fee.But,we do pay our college tuition fees.The policy was unfortunately not stated before the beginning of the project. My project is an individual one and the institute uses it like a building block for a much bigger one. I made a mistake in not being brave enough in asking...

Conscience cleared-up now. Guess one can't learn electronics without failures.

I am doing a project in my institute, which happens to be compulsory for every student that takes the course. Unfortunately,while experimenting with some electronics, I fried a circuit board which costs around 9 euros/12 US dollars. How does student ethics fit into this scenario? It was...

The above solution of x(t) does not work for x(0)=0. Is there an inherent assumption that I am missing? I wrote the solution I got for the D.E x'=x(1-x) below. After substituting for x(0)=0,I get a fraction that tends to 1. x(t)=\frac{1}{1+C_1*e^{-t}} \\ x(0)=\frac{1}{1+C_1} \\ C_1=x(0)-1 \\...

I am going to quote an article below and there is a part I would like clarification.I do not understand why chaotic differential systems do not have an analytical solutions. In the simplest form,an equation such as this one [sin(x) + x - 0.5 = 0] does not have an analytical solution i.e it can...

Jobrag:Before some of the components got fried,I could just rotate the voltage knob and it would go all the way to 12V. After I took away some of the burnt-up modules,I am faced with this problem. If what you say about current limiter is true,I could actually not rotate the current knob AT-ALL...

A problem existing with my Dc Power supply when there is too much load(i.e chip TPIC1021) on it. As you can see in the video below,there are 2 knobs-one for changing the voltage and the other for changing the current. Normally,I would just change the volt knob but after my bluetooth module got...

I'm using a DC power supply connected to a TPIC 1021 chip(basically a serial transceiver). I need 12V to power the chip and my DC power supply is equipped with 2 knobs,one changes the voltage and the other changes the current. For some reason,when I get to 5V and turn the volt knob...

Why do I need a "processing" code when I pair Arduino with bluetooth I have a need to connect my [Arduino+Bluetooth dongle JY-MCU V1.02] to my laptop in-built bluetooth device.Most forums suggest using a processing code to go ahead and do this...

I have a 1K ohm potentiometer.(datasheet is attached below). My aim is to convert 12V to 5V,which I would then apply to power the Arduino microcontroller. I'm not quite sure if I CAN use the potentiometer I have ie T93 YA 1K 1035 to do this conversion. The datasheet says that the maximum...