Yes, that was also one of my intended applications. But I really like the prototype like oscillation of the semaphore hand, and that was a complete failure on this servo. So, I'm not gonna do it ;-)
Interesting video. I bought a couple of linear servos some time ago with the thought about using them to activate an N-scale turnout. I thought it might be possible to attach the servo to the underside of the turnout such that I had it in one unit. This way I could easily replace the turnout and servo if anything went wrong. I haven’t gotten back to that project yet. This video gives me some more to think about. The spring on a PECO turnout might be too much for the servo. Still, since the linear servo stays in position and won’t move back, removing the PECO spring may be the solution. I may end up using these servo for animation projects anyway. Enlightening video as always Hans!
@@pierrelambert446 I've standardized on a SG90 servo with a 3d printed holder for my turnouts. They have been working great with the Green Hat. For a few of the KATO turnouts that I use, I now have Hans' relay board adapter. Love his products!
@@robleathley6024 great to hear, I have now 4 green hat, and a few yellow hat for track occupancy. And around 10 servo SG90s installed. My layout construction is a bit slow. I did design my own servo mount. Hans product are working great. He his helping to push the envelope of this hobby.
@@pierrelambert446 My layout isn't going any faster. So many projects and so little time! I have about 20 servos installed so far with another 8 or so yet to be done. The Green Hats will all control them. I'm also using MGP diode detectors for my occupancy detectors to allow signaling on the mainline. I have a few other MGP items as well. They work well with Hans' system. I very much agree that he is pushing the envelop in this hobby.
@@robleathley6024 I just stopped purchasing the Yellow Hat for my MGP detector, as the Red hat with DCC ++ should come with 32 inputs. I am on stand by for the detection. Look like we are on the same path for the electronic off our layout.
Great Video! I have a project where I am using 76 of these servos and I was using 50Hz and in some cases getting jitters and stalls, I will give this a shot with the 100Hz and see if I get an improvement. Thanks a million! It has been really hard to find technical info on these.
Thank you. Running 100 Hz if the servo can handle it is generally a good idea as it also gives higher resolution. Some of it probably will be lost by the gears, but at least you can play with it. Overall, as I think is made clear in the video, I was not very impressed by the worm gear mechanics of this servo. For a project like yours I probably would look for a more reliable device.
Thanks for your very informative review of these little servos. I have been looking at them for turnout control instead of sg90’s, but I’m not so sure now. Thanks again, very helpful video.
I am considering using this servo for switching turnouts on a small portable N-scale layout. I think it could be ok for this application since the switch rails barely need to move a few mm. But I am finding it difficult to create an elastic connection with the throwbar of the turnout since I don't want to stall the servo. Also, how did you slow down the speed of the servo? By reducing the voltage? I am currently driving the servo at 3.3V directly from the PWM output of a Raspberry Pi.
The advantage is it is small and linear, but I would be cautious about the relatively short life span. Since the gear is not back drivable, you don't need a lot of elasticity in the draw bar, you just drive the servo to the right position. To control the moving speed of the servo, watch my videos 17 and 18. There it is explained in detail and you also find a link to the Arduino sketch. And watch video 55 for a demonstration what movements are possible.
Thank you for the review. I am thinking about using this type of small servo to raise and lower the pantograph in my TT-scale locomotive. There are decoders that can control servos directly. The problem is probably the small space in the loco and the power supply. Because the decoders usually provide only 50mA at 5V. That will not be enough for this servo.
@@macg9940 Yeah, I experimented with memory wire a while ago. Current, heat, and little precision, unfortunately. On the other hand, a good geometry to put into a locomotive body.
Thanks Hans for your review and recommendation. I am interested in this type of review for moving turnout servos as I have bought a DS78V (digitrax), but it does not have any means of adjusting the end stop positions for point end positions, and risks breaking the turnout through unregulated digital movement. I was hoping that this might have a means of adjusting the throw length, but I dont think that it will help. If you come accross a means to control the stop end movements on a servo digitally, that can be used with the ds78v , please do publish it. Many thanks Jonathan Dorey
Hans green hat is doing the same task as the ds78v and it is fully compatible with loconet. The advantage of the green hat is configured by a web page it offer a lot more ajustements and features. Since the brain is the ESP32 microcontrollers. Take a look at his video on the green hat on his channel.
I checked the Digitrax manual as well as the groups.io news group and indeed it seems the Digitrax DS78V only has fixed positions for the servos. Not very convincing, I must say. They suggest mechanical adjustments (meaning moving the servo until it fits). Sort of unbelievable. As you may have seen in the video, on the GreenHat config page I provide a slider to determine the exact servo position - individually for every servo and for every possible position (if you use it to drive a signal with say 5 aspects, you have 5 positions that you can set). I always felt this is the way to do it properly.
Thanks, an excellent review. I agree with your conclusions. I used these on a couple of H0 lower quadrent signals and was disapointed. The linear servos I aquired looked the same as the ones in your review. They were very easy to burn out, and were unable to produce signal bounce, for the same reason you showed. I was able to slide the gear on the screw to eliminate the backlash, but the motion was still rough and much noiser than the 9g alternatives I am using.
Interesting topic and timing. I recently installed 14 MTB MP1 turnout motors on my layout. They have a built in switch and are a bit more expensive than a Peco coil and switch but are more reliable. I’ve tried controlling them using the MGP turnout decoders and the Team Digital SMD84 turnout decoders to see what options are provided. I will next test them with the Green hat. One thing I like is that if the turnout is already set in the correct direction, if you select a route that includes the same turnout and direction, there is no movement. Unlike the Peco coil that will reenergize the coil in the same direction. I will also test feedback.
Not sure about the MP1. Is that like a servo? Or like a slow motion DC motor? In the latter case they would not work with the GreenHat, except when using the coil drive attachment as shown in Video #78. The Greenhat/IoTT Stick is memorizing the last turnout position when powering down, so when you come back, it already knows it. Also, retriggering the same switch does not reactivate the coil as it remembers the current position. Of course, this falls flat if you manually change the position while the GreenHat is off...
Tam valley do a nice servo driver for this application Mini singlet I think they are called I have a couple on my layout driving these servos converting basic manual Bachmann set track to DCC controlled turnouts
@@Riya.79 You can connect it directly to the Arduino as shown in the Arduino documentation here: docs.arduino.cc/tutorials/generic/basic-servo-control/ or here: ua-cam.com/video/kUHmYKWwuWs/v-deo.html For most applications (i.e. if you want to control a number of servos from the same Arduino) you probably will use a PWM driver such as a PCA9685 board.
Nice, I was not aware those servo were existing. Thanks for sharing. I am looking at your tindie store almost everyday for the purple hat. If you try the servo sg90s with metal gear, the servo won’t move when the power is removed. At lest without excessive force. A bit more expansive than the regular sg90. For my layout i will only purchase the sg90s.
At approximately 19 seconds into the video I think you had better correct the servo connector wire/pinout colours, the brown is the negative and the yellow is the signal.
Yes, it probably should be the other way around. Funny enough, the image comes from a commercial product description..... Anyway, in real world, there are several different color schemes as seen here: static.rcgroups.net/forums/attachments/3/0/1/8/a4228312-146-user38_pic55606_1294883044.gif The important thing is that all of them carry the plus on the center pin so that there is no harm done to the servo if you connect it the wrong way around. It just does not work.
Unfortunately it is not possible in UA-cam to make changes to a published video. But as common in such cases, I added a bug report in the video description.
Dear Mr. Tanner, Thank you very much for sharing your research about servos with the model railroad community. There are also tiny stepper motors, maybe they are an option for tiny spaces and could also be used with the green hat? I would be very happy to hear about that, since tiny stepper motors seem to be very versatile... Here are some videos about steppers, which might be interesting for you: ua-cam.com/video/MaByP2w_vtA/v-deo.html ua-cam.com/video/j2F3jv8YaSM/v-deo.html Kind regards and thank you very much HappyBricks
Thanks Hans! I used some of these in my G scale semaphores. Glad to see Im not the only one who's not terribly impressed with their performance.
Yes, that was also one of my intended applications. But I really like the prototype like oscillation of the semaphore hand, and that was a complete failure on this servo. So, I'm not gonna do it ;-)
Interesting video. I bought a couple of linear servos some time ago with the thought about using them to activate an N-scale turnout. I thought it might be possible to attach the servo to the underside of the turnout such that I had it in one unit. This way I could easily replace the turnout and servo if anything went wrong. I haven’t gotten back to that project yet. This video gives me some more to think about. The spring on a PECO turnout might be too much for the servo. Still, since the linear servo stays in position and won’t move back, removing the PECO spring may be the solution. I may end up using these servo for animation projects anyway. Enlightening video as always Hans!
Yes, I always remove the springs on the turnout. The sg90s work great with my n scale peco turnout.
@@pierrelambert446 I've standardized on a SG90 servo with a 3d printed holder for my turnouts. They have been working great with the Green Hat. For a few of the KATO turnouts that I use, I now have Hans' relay board adapter. Love his products!
@@robleathley6024 great to hear, I have now 4 green hat, and a few yellow hat for track occupancy. And around 10 servo SG90s installed. My layout construction is a bit slow. I did design my own servo mount. Hans product are working great. He his helping to push the envelope of this hobby.
@@pierrelambert446 My layout isn't going any faster. So many projects and so little time! I have about 20 servos installed so far with another 8 or so yet to be done. The Green Hats will all control them. I'm also using MGP diode detectors for my occupancy detectors to allow signaling on the mainline. I have a few other MGP items as well. They work well with Hans' system. I very much agree that he is pushing the envelop in this hobby.
@@robleathley6024 I just stopped purchasing the Yellow Hat for my MGP detector, as the Red hat with DCC ++ should come with 32 inputs. I am on stand by for the detection. Look like we are on the same path for the electronic off our layout.
Great Video! I have a project where I am using 76 of these servos and I was using 50Hz and in some cases getting jitters and stalls, I will give this a shot with the 100Hz and see if I get an improvement. Thanks a million! It has been really hard to find technical info on these.
Thank you. Running 100 Hz if the servo can handle it is generally a good idea as it also gives higher resolution. Some of it probably will be lost by the gears, but at least you can play with it. Overall, as I think is made clear in the video, I was not very impressed by the worm gear mechanics of this servo. For a project like yours I probably would look for a more reliable device.
Thanks for your very informative review of these little servos. I have been looking at them for turnout control instead of sg90’s, but I’m not so sure now. Thanks again, very helpful video.
Do it as I did: Buy two, test them and draw your own conclusions. I decided to go with SG 90's ;-)
I am considering using this servo for switching turnouts on a small portable N-scale layout. I think it could be ok for this application since the switch rails barely need to move a few mm. But I am finding it difficult to create an elastic connection with the throwbar of the turnout since I don't want to stall the servo. Also, how did you slow down the speed of the servo? By reducing the voltage? I am currently driving the servo at 3.3V directly from the PWM output of a Raspberry Pi.
The advantage is it is small and linear, but I would be cautious about the relatively short life span. Since the gear is not back drivable, you don't need a lot of elasticity in the draw bar, you just drive the servo to the right position. To control the moving speed of the servo, watch my videos 17 and 18. There it is explained in detail and you also find a link to the Arduino sketch. And watch video 55 for a demonstration what movements are possible.
Thank you for the review. I am thinking about using this type of small servo to raise and lower the pantograph in my TT-scale locomotive. There are decoders that can control servos directly. The problem is probably the small space in the loco and the power supply. Because the decoders usually provide only 50mA at 5V. That will not be enough for this servo.
Working panto for TT scale? That's beyond challenging! Hopefully you post a picture somewhere when that works!
@@IoTT I wouldn't be the first. Others have used Nitinol wire (Memory wire). Unfortunately, this requires 200mA current to hold the position.
@@macg9940 Yeah, I experimented with memory wire a while ago. Current, heat, and little precision, unfortunately. On the other hand, a good geometry to put into a locomotive body.
Thanks Hans for your review and recommendation. I am interested in this type of review for moving turnout servos as I have bought a DS78V (digitrax), but it does not have any means of adjusting the end stop positions for point end positions, and risks breaking the turnout through unregulated digital movement.
I was hoping that this might have a means of adjusting the throw length, but I dont think that it will help.
If you come accross a means to control the stop end movements on a servo digitally, that can be used with the ds78v , please do publish it.
Many thanks
Jonathan Dorey
Hans green hat is doing the same task as the ds78v and it is fully compatible with loconet. The advantage of the green hat is configured by a web page it offer a lot more ajustements and features. Since the brain is the ESP32 microcontrollers. Take a look at his video on the green hat on his channel.
I checked the Digitrax manual as well as the groups.io news group and indeed it seems the Digitrax DS78V only has fixed positions for the servos. Not very convincing, I must say. They suggest mechanical adjustments (meaning moving the servo until it fits). Sort of unbelievable. As you may have seen in the video, on the GreenHat config page I provide a slider to determine the exact servo position - individually for every servo and for every possible position (if you use it to drive a signal with say 5 aspects, you have 5 positions that you can set). I always felt this is the way to do it properly.
Thanks, an excellent review. I agree with your conclusions. I used these on a couple of H0 lower quadrent signals and was disapointed. The linear servos I aquired looked the same as the ones in your review. They were very easy to burn out, and were unable to produce signal bounce, for the same reason you showed. I was able to slide the gear on the screw to eliminate the backlash, but the motion was still rough and much noiser than the 9g alternatives I am using.
Thank you. Looks the problems are consistent. And yes, I forgot to mention the noise level in the video. It is probably louder than the SG90.
Interesting topic and timing. I recently installed 14 MTB MP1 turnout motors on my layout. They have a built in switch and are a bit more expensive than a Peco coil and switch but are more reliable. I’ve tried controlling them using the MGP turnout decoders and the Team Digital SMD84 turnout decoders to see what options are provided. I will next test them with the Green hat.
One thing I like is that if the turnout is already set in the correct direction, if you select a route that includes the same turnout and direction, there is no movement. Unlike the Peco coil that will reenergize the coil in the same direction. I will also test feedback.
Not sure about the MP1. Is that like a servo? Or like a slow motion DC motor? In the latter case they would not work with the GreenHat, except when using the coil drive attachment as shown in Video #78.
The Greenhat/IoTT Stick is memorizing the last turnout position when powering down, so when you come back, it already knows it. Also, retriggering the same switch does not reactivate the coil as it remembers the current position. Of course, this falls flat if you manually change the position while the GreenHat is off...
Tam valley do a nice servo driver for this application
Mini singlet I think they are called
I have a couple on my layout driving these servos converting basic manual Bachmann set track to DCC controlled turnouts
Hello sir can i program my ultra linear micro servo with arudino ?
The GS-1502 control interface is the same like any other servo. It just needs a PWM signal with a frequency between 50 and 100Hz
@@IoTT and we need another device to control it other than aurdino ??
@@Riya.79 You can connect it directly to the Arduino as shown in the Arduino documentation here: docs.arduino.cc/tutorials/generic/basic-servo-control/ or here: ua-cam.com/video/kUHmYKWwuWs/v-deo.html
For most applications (i.e. if you want to control a number of servos from the same Arduino) you probably will use a PWM driver such as a PCA9685 board.
Nice, I was not aware those servo were existing. Thanks for sharing. I am looking at your tindie store almost everyday for the purple hat. If you try the servo sg90s with metal gear, the servo won’t move when the power is removed. At lest without excessive force. A bit more expansive than the regular sg90. For my layout i will only purchase the sg90s.
The SG90 is certainly the better option. More durable and better drive precision.
At approximately 19 seconds into the video I think you had better correct the servo connector wire/pinout colours, the brown is the negative and the yellow is the signal.
Yes, it probably should be the other way around. Funny enough, the image comes from a commercial product description.....
Anyway, in real world, there are several different color schemes as seen here: static.rcgroups.net/forums/attachments/3/0/1/8/a4228312-146-user38_pic55606_1294883044.gif
The important thing is that all of them carry the plus on the center pin so that there is no harm done to the servo if you connect it the wrong way around. It just does not work.
@@IoTT Regardless of the lack of damage if the wires are reversed, you should still correct the diagram in the video.
Unfortunately it is not possible in UA-cam to make changes to a published video. But as common in such cases, I added a bug report in the video description.
Excellent video. Informative and clear. Glad I subscribed.
Thank you and Welcome to the channel!
Dear Mr. Tanner,
Thank you very much for sharing your research about servos with the model railroad community. There are also tiny stepper motors, maybe they are an option for tiny spaces and could also be used with the green hat? I would be very happy to hear about that, since tiny stepper motors seem to be very versatile...
Here are some videos about steppers, which might be interesting for you:
ua-cam.com/video/MaByP2w_vtA/v-deo.html
ua-cam.com/video/j2F3jv8YaSM/v-deo.html
Kind regards and thank you very much
HappyBricks
Those motors will be useful to do layout animation.
Thanks for the links, very cool. I just ordered a bunch as some application ideas crossed my mind ;-)