王月月 Posted January 16, 2017 Share Posted January 16, 2017 On 2017/1/13 at 8:39 PM, Rehab1 said: I agree! I must say Wang Yue Yue is much more pleasing to the eye than EUC representatives in the US! @Jason McNeil sorry buddy! HAHA, so do i need to change my avatar? But i like this beautiful girl. hahaha Link to comment Share on other sites More sharing options...
王月月 Posted January 16, 2017 Share Posted January 16, 2017 On 2017/1/13 at 9:24 PM, KingSong69 said: Please give me a better understanding of what of that letter is great stuff here....cause i can't see any "Somewhat?"???? Somewhat what? How do i know? :-) A sag under 60V can even happen on a nearly full, ,lets say 65Volt Batterie....... I think KS and GW are doing a much better Job with for example 80% alarms, high draw alarms, or getting the Speed automatically down if Batterie under a certain percentage (KS: <40%=25kmh max and going even slower on lower bat , GW <20% warning beeps, tiltback) What especially "stinks" me off is that the Zero is also sold with 130wh as 30kmh wheel...... Ooooh.......and just to have something good about the latest -brandnew- Gotway MCM3 V2 (580bucks)...only produced with 260wh, announced with 30kmh !!! It Cuts out in free spinning at 48kmh...and under load (with 75kg !!!) at 43kmh!!!.... Even with an Batterie under 20% it was able to go WITH Load up to 38 kmh: Full Proof test: Here There are many other things to affect and control the speed, such as motor, control board, program and so on. Safe speed is our goal. Link to comment Share on other sites More sharing options...
王月月 Posted January 16, 2017 Share Posted January 16, 2017 On 2017/1/14 at 0:43 AM, Slaughthammer said: Chris, I really appreciate you doing this. Big thanks for your work! Is there a way to make this sentence more comprehensible? This reads to my as if written by someone who doesn't have the slightest clue what the terms RPM, torque and voltage mean, not to speak how they depend on one another... You know because your wheel tilts back. All IPS Wheels have a battery voltage dependend tiltback. On my Lhotz, if the battery is full, it will tilt back just under 30 kph, but if the battery is near empty, it will start at 23 kph. This tiltback is not removeable by the user as it is on those Gotways... ;-) Yes, these features lack documentation by IPS, it would be really nice to get proper docs with the wheel, or even better, in advance of purchasing on on the internet. As for the power figures, I would guess that IPS calls short term max power output, not max continuous power output. I come to this conclusion because if I would lean on my 1000W rated lhotz as much as I see other riders doing on wheels rated for 800W cont. and 1500W peak, I would faceplant a lot. Thanks for your advice, we will create and edit some docs to show IPS wheels more clearly. The wheel performance about max speed, max mileage and uphill angle is all depend on its design and structures, so that there are many professional terms and data support based on tests. We have test platform to make tests. Tiltback is set as one of the protective step, such as top speed. Battery provides the power, when the wheel calculates if there is not enough power to support the speed, it will warn you, tiltback. About the power output, i will give response soon. Thank you very much. Link to comment Share on other sites More sharing options...
MaxLinux Posted January 16, 2017 Share Posted January 16, 2017 2 hours ago, 王月月 said: HAHA, so do i need to change my avatar? But i like this beautiful girl. hahaha I like this beautiful girl! Link to comment Share on other sites More sharing options...
lizardmech Posted January 16, 2017 Share Posted January 16, 2017 Does IPS design all their controller hardware themselves? I noticed their designs are different to other brands in general. Link to comment Share on other sites More sharing options...
Chris Westland Posted January 18, 2017 Author Share Posted January 18, 2017 Yue Yue asked me to upload this short video of their tests on their dynamometer. She didn't like the background sounds, but these are fine. I tried to add a musical sound track per her specifications, but sadly failed. Anyway, click here to see her MP4! Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 20, 2017 Share Posted May 20, 2017 On 1/12/2017 at 5:50 PM, Marty Backe said: This is great stuff. Now can someone do this for Gotway Lol. GOTWAY can not do this because they don't design the board. Gotway controller is very basic and generic. Look how they updated the 84v. They could not design a proper board so they hacked and put a daughter board on top. Even the 67v was hacked by putting more MOSFET behind. GOTWAY need to own the code and design and make it better. Even their phone app is useless. I love my MCM4 but GOTWAY need to step up. With their own technology. Link to comment Share on other sites More sharing options...
Carlos E Rodriguez Posted May 20, 2017 Share Posted May 20, 2017 On 1/16/2017 at 0:06 AM, MaxLinux said: I like this beautiful girl! I am in love! Link to comment Share on other sites More sharing options...
Christoph Zens Posted May 21, 2017 Share Posted May 21, 2017 On 13.1.2017 at 0:33 AM, Chris Westland said: In the design of the motor, the power draw should place battery voltage somewhere in the middle when RPMs will move the EUC at 30km/h with torque that is greater than 20N⋅m. On 13.1.2017 at 5:43 PM, Slaughthammer said: Is there a way to make this sentence more comprehensible? This reads to my as if written by someone who doesn't have the slightest clue what the terms RPM, torque and voltage mean, not to speak how they depend on one another... Let me try to rephrase this a little: I think what 月月 wanted to mention is that their engineers don't just pick a motor which can reach the necessary RPM to go 30kph somehow, but they first define a specific target operating point which they verify through actual measurements on the dynamometer (like the 20Nm torque required to move an 80kg rider at 30kph on a level surface) and then make sure the motor is designed such that its characteristics match up with the requirements. A brushless DC motor as used in EUCs has a certain free running top speed, which depends on the available drive voltage. That speed is the point where the induced back EMF equals the drive voltage. Even without any load, the motor can't go faster than this, but at this speed, there is zero torque left, so this is no practically usable operating point. On the other hand, when RPM is low, torque is high since back-EMF is low and most of the drive voltage is available at the coils to induce strong magnetic fields. So the torque curve will start high and go down as RPM goes up. Now consider that power euqals torque times RPM. If we normalize torque and RPM values to range from 0 to 1 (or 0% to 100%), and further assume that torque will go down linear with RPM going up, we get the typical quadratic curve for torque x RPM. This curve has its maximum at 0.5 (or 50%), since 0.5 x 0.5 = 0.25. Any other combination yields lower results (try 0.6 x 0.4 = 0.24, 0.8 x 0.2 = 0.16, or even 0 x 1 = 0). For clarification, here is a sample plot of the things I am talking about: This is where Yu-Yus comment comes into play: At 30kph,they want to make sure their motor is running at this peak power operating point such that the available power output is at the maximum the motor can deliver. At this operating point, torque values will be down by 50%, as back-EMF is already at 50% of the drive voltage (leaving half the drive voltage to deliver the 20Nm torque). So what Yu-Yu is getting at is that they are making sure their motor is able to deliver more than 20Nm of torque with half the drive voltage, which is battery voltage reduced by ohmic losses inside the battery itself as well as cables, connectors, and power MOSFETs). I hope the 'place the battery voltage somewhere in the middle' comment makes more sense now. Of course it is subject to debate if the peak power operating point should be the target for the wheels maximum cruising speed. Other options are possible and could be argued as well. Also, I would challenge the 80kg flat terrain assumption. If the design aims for that, it will cause the many faceplants we see with heavier riders going at max speed and NOT slowing down when approaching an uphill section on their route. It happens over and over again. Of course these are driver errors, caused by people not understanding how their EUC works (we need EUC trainings, like we have for driving a car), but still. If the target operating point is a 10% incline instead of a flat surface, the wheel will have some power reserve for that unsuspecting rider... Link to comment Share on other sites More sharing options...
Christoph Zens Posted May 22, 2017 Share Posted May 22, 2017 I need to add some clarification about my comment regarding desired operating point. What I get from 月月 message is that they aim for the max power output point at max rated speed (30kph). I noted that designing the motor such that it operates at some other point at 30kph would be possible as well. I, for my part, would aim for an operating point closer to max efficiency. Sure, the motor does not deliver its full potential power, but it runs at much higher efficiency, producing less heat. The only problem is that the motor as a whole would have to be stronger and thus heavier, since it still needs to deliver the 20Nm torque, but now at half its max possible output. I guess that's what we get when we choose a stronger wheel. Effectively we operate the motor of such a wheel closer to its max efficiency, compared to a smaller wheel, which may barely be able to deliver the torque we demand. Check out this graph: Link to comment Share on other sites More sharing options...
IPS Malta Posted November 27, 2017 Share Posted November 27, 2017 This thread seems to have gotten inactive and still IPS is still doing research and improvements on the new products. Back to the above, the concept of being the safest wheel with innovation is always there with IPS which is why one would probably get and stick to IPS. Most people won't think about the technicalities but more of something that delivers their objective. As for the beautiful girl at IPS... the flowers continue to blossom hope she don't mind about this pic she shared on another network Link to comment Share on other sites More sharing options...
Stan Onymous Posted July 11, 2018 Share Posted July 11, 2018 I really cannot wait to get my S5 so I can see how these two motors and systems manage the power better than lets say their T-350, which I thought was amazing. I will of course do a written review and a video review which I will post here and elsewhere. The IPS needs more introduction to America, where the muscle EUCs and the speedy EUCs seem to dominate. There seems to be a lot of room for an exciting well placed niche vehicle like the S5 if all performs well as expected from the adverts. Just Last week I tried the KS 14s on some off road trails and roads at Griffith Park in Los Angeles. It was fun again to ride a powerful smaller tire vehicle around that was capable enough for a 150lb rider. I am so looking forward to the new s5. It looks kinda buff in a mini way. Link to comment Share on other sites More sharing options...
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