Oh boy...the propellers are really starting to spin on the helmets now! PID's...NERD ALERT!!!
Sure, this thing will have a PID on the torque-loop, but the smoothness of onset and cut-off of power delivery is more down to jerk rates (yes, there's a thing in control systems called jerk rate), and also some other settings that can be adjusted that are generally more analogous to deadband, or dwell time. If the PID wasn't tuned right, you'd feel the crank surging as you pedaled (oscillations), or else lagging your stroke (overdamped). I haven't seen that characteristic in any proper e-bike I've worked on. Sketchy Costco ones, sure. But no reputable ones. I reckon the engineers at Shimano or Bosch have seen and tuned a PID or two ;) STEPS has been around since 2014, so they've had lots of time to get the bugs out. I've tuned many hundred PID's now, and don't think I could do much better than what is in the motors I've seen.
On the Shimano systems which I work on the most, they have some basic settings for users to adjust in the basic app/software. But if you get the more in-depth access (that shall not be named) then you can massage different parameters to address some of the issues that they come with out of the box.
Biggest issue out of the box: power carrying on after pedaling stops. Very prevalent in BOOST mode. You can tune that out pretty easy with the advanced features. But the Shimano system is the least tunable. Bosch is next. Specialized are more tunable. And I bet this system for RM (never worked on one) has some good access as it is only for them and a more 'boutiquey' powertrain system. I'd be keen to look under the hood of one sometime.
Shimano & Bosch systems have to work for so many different bikes and configurations that they have quite vanilla tuning and firmware. But OEMs like Norco, Kona, Trek, etc. have model specific firmware versions that do make it more customized to the bike. Incorporating things like motor angle and other variables that affect how the motor responds to clocking of the pedals for example are important to get the power delivery just right.
If you feel like your Shimano or Bosch isn't quite right, take it into the shop you got it from and ask them to verify it came loaded with the right firmware. I've seen quite a few e-bikes that have vanilla firmware and only a few picky customers that complained about some quirky behavior that I took the deep-dive on it and found that we needed to get OEM access and load the bike-specific parameters. Some it helped, others still felt it was quirky. But they were quirky customers too :)
Oct. 30, 2021, 9:59 p.m. - rockford
Oh boy...the propellers are really starting to spin on the helmets now! PID's...NERD ALERT!!! Sure, this thing will have a PID on the torque-loop, but the smoothness of onset and cut-off of power delivery is more down to jerk rates (yes, there's a thing in control systems called jerk rate), and also some other settings that can be adjusted that are generally more analogous to deadband, or dwell time. If the PID wasn't tuned right, you'd feel the crank surging as you pedaled (oscillations), or else lagging your stroke (overdamped). I haven't seen that characteristic in any proper e-bike I've worked on. Sketchy Costco ones, sure. But no reputable ones. I reckon the engineers at Shimano or Bosch have seen and tuned a PID or two ;) STEPS has been around since 2014, so they've had lots of time to get the bugs out. I've tuned many hundred PID's now, and don't think I could do much better than what is in the motors I've seen. On the Shimano systems which I work on the most, they have some basic settings for users to adjust in the basic app/software. But if you get the more in-depth access (that shall not be named) then you can massage different parameters to address some of the issues that they come with out of the box. Biggest issue out of the box: power carrying on after pedaling stops. Very prevalent in BOOST mode. You can tune that out pretty easy with the advanced features. But the Shimano system is the least tunable. Bosch is next. Specialized are more tunable. And I bet this system for RM (never worked on one) has some good access as it is only for them and a more 'boutiquey' powertrain system. I'd be keen to look under the hood of one sometime. Shimano & Bosch systems have to work for so many different bikes and configurations that they have quite vanilla tuning and firmware. But OEMs like Norco, Kona, Trek, etc. have model specific firmware versions that do make it more customized to the bike. Incorporating things like motor angle and other variables that affect how the motor responds to clocking of the pedals for example are important to get the power delivery just right. If you feel like your Shimano or Bosch isn't quite right, take it into the shop you got it from and ask them to verify it came loaded with the right firmware. I've seen quite a few e-bikes that have vanilla firmware and only a few picky customers that complained about some quirky behavior that I took the deep-dive on it and found that we needed to get OEM access and load the bike-specific parameters. Some it helped, others still felt it was quirky. But they were quirky customers too :)