Commercial Version of Sensor Network Shield (follow-up report)

y: Yuuki Okamiya

Hello All, This is Yuuki Okamiya from Gadget Renesas.

The circuit and pattern of Sensor Network Shield (Kurumi Eye Shield) is fixed and sold by TESSERA.

The offical product name is now Sensor Network Shield (Part No.: TSA-SN500). 

We have integrated the great comments you all have sent us. And just for fun, we created a φ3 hole for attaching a mini motor and universal plate.

A few consideration are made as follows:

  • Interface for directly attaching FTDI for configuring XBees using X-CTU (KURUMI does not require through-mode setting),
  • A micro-B USB connector for connecting an Android's battery BOX or other accessories to support lithium 3.7V to XBee ratings
  • A regulator to ensure stable 3.3V power supply. I’m not sure how stable operations will be, but give it a try!

***Previous Entry***

Thank you for your continued support of Gadget Renesas.

We are happy to announce that Tessera Technology will be manufacturing the commercial version of the Sensor Network Shield which many of you in the SKAURA Board User’s Forum has kindly tested for us.

The SNShield should be ready for sale in March or April. We sincerely thank all of the producers who presented their projects at Renesas Night 4.

Related blogs are as follows:

Summary of improvement ideas based on prototype are as follows:

We should be able to include most suggestions or requests submitted by February 5, so please feel free to send us your ideas!

 If anyone who sent in requests would like to plan a workshop, we can provide prototypes for 10 to 20 people for free!

 Please feel free to leave comments here. We can deliver prototypes at Regular Evening Workshops”.

Remove the D6 RESET connection, connect to SLEEP_RQ (with short pad, through hole)

Connect LED (with short pad) to XBee Association pin (pin 15)

Connect Push button to XBee Commissioning button (pin 20) (depending on layout)

Replace D3 and D5 Pch-MOSFET circuit with BD6211F circuit (full bridge for motor use)

Mount step-down regulator to borad and supply 3.3V to Vcc (also consider the Arduino Pro Mini 5V).

Include the USB micro B connector, enable power supply

Adjust through-holes for input to SmartAnalog by half a grid.

Make sure the sensor side of the mini board is extra thin for each separation. If possible, use V cut.

Use V cut to enable easy separation of restricted areas for screw holes.


--- COMMENTS --- 



You’ve done it!

The thing is, although the request to be able to run a motor was integrated in the board, there is an I/O pin right under KURUMI, making it very difficult to use.

I humbling propose that the I/O hole located immediately under KURUMI be moved to a more accessible spot..


Okamiya Yuuki

Thank you for the congratulatory words! I agree with your issue concerning the I/O hole, but we struggled with that or making the board larger. While striving to use BD6211 for the motor drive section, like a mini 4-wheel drive toy, directional change was based on servo control via a different pin. Therefore, the two output pins on BD6211 were positioned for easy external wiring, and we wanted to do the same for the servo control pin. Actually, we think the driver circuit is vital because it can output sound from the speaker. Let us know if you prefer the current setup with the Pch-MOSFET circuit as is.



If there are also plans to change the external dimensions and properties of the board, I would like to have something like the Takachi plastic case, with the case left un-finished, dimensions that allow screws to be tightened, and mounting holes.

I also want to be able to place the device outdoors and let it run on a solar battery.



I think it might be better to not have a mounted light sensor and allow the user to integrate as need be.

When using a solar battery, a diode for backflow prevention would help for direct connection to a panel. Maybe not?


>Replace D3 and D5 Pch-MOSFET circuit with BD6211F circuit (full bridge for motor use)

Wouldn’t this limit movement to forward and reverse? What would this be useful for?



> Actually, we think the driver circuit is vital in that it can output sound from the speaker.


That makes sense.



How about if your make two types--one for movement and one for sensors?



>  Actually, we think the driver circuit is vital because it can output sound from the speaker.

The thing is, you can’t directly connect a speaker, can you? You would need a large capacitor.


Okamiya Yuuki

Direct connection to the speaker produces a really good sound, but does it definitely require a capacitor? I’m not sure. Concerning the motor drive (forward and reverse), I was picturing about a 3-wheel vehicle, like you often see in India, using another servo for the front wheel. Still, I haven’t tested it out yet so I don’t know if it will work. I think it might work to add another shield for the drive section. It would be nice if KURUMI could speak “welcome home!”.  We are thinking about changing the external dimensions of the board. Takachi offers loads of cases and we haven’t figure out which is the best one yet. If you have a suggestion about cases, please let us know! We will probably add the light sensor just to see how it works. Pins can be switched using SmartAnalog, so we plan adding more sensors. (あるいはenabling users to add more sensors). In the end, we also have to confer with Tessera about the target price.



 I hope you are not talking about a piezoelectric speaker, because a direct current would be a really bad idea.

If you use what they call a D-class amp you might not need a capacitor.

And if you raise the PWM carrier frequency, you can but the noise so that it is inaudible. But if you raise the carrier frequency too much, the interrupts may become invalid.



Should you include a guarantee of a fixed output?

Well, if output is set to Hi in the program, it may cause failure, but isn’t that true with any system? And should that be considered with the system costs?



What I mean is, if you are using a drive circuit intended for a motor, I think you have to include a capacitor or something, rather than a direct connection.



The case…I can’t come up with any particular one that is best. Here are a few thoughts:


If the board is also for outdoor use, we need a waterproof case:


For attachment to walls, it needs some kind of flange:


This one is good for including a battery:


In addition, if the mount hole placement could be on a 5mm pitch grid, screws can be used on Tamiya’s universal plate, which looks like it is used often for moving parts.


Another popular choice is the combination of the crawler set and twin gear box here:


The crawler seems to be more durable, and the small size, adjustable torque of the gears even for heavier loads, makes it easier to make moving gadgets.

But that would require two motor drivers.



Thank you all for the great information. KURUMI can drive the Tamiya motor but it isn’t all that great. I was thinking of mounting the following motor ( but there is no way to attach it. We are still thinking about things but maybe we do have to deal with moving gadgets and visual gadgets separately.



The SA shield demo presented on Renesas Night used the Tamiya 130 motor with exactly this configuration.



Really?! I need to dig up the documents from that night. By the way, how were the sensor and other values when the motor was running?


Fujita Nozomu

> Tamiya motor

Tamiya offers a smaller motor than MabuchiIs FA-130.

It comes in various gear boxes and looks pretty easy to use.


I’d like to see something “eco-related.” Would that be possible?



Sorry. About the Mabuchi FA-130 motor…

By the specifications, it looks the same as the motor put out by Sengoku.

And the gear box is wrong too. It should be the double gear box that allows you to set slower speeds.

The 130 motor is included.

Regarding any affect on the sensor: for the power supply I used a 2-port mobile battery when using the SA Shield. I have also used 4 batteries to run a gadget.

So, a power supply regulator is mounted on the board, right?

I separated the power supply for the drive and control systems.


Kurauchi Makoto

I would like to get rid of the Lego holes?


Fujimoto Masashi

Is there only one full-bridge (BD6211F)? In other words, because the motor only goes forward and reverse, you only need one full-bridge, right?

How about configuring the board so that power supply can be separated for the sensor and motor systems by the user as needed with a solder short?

You could increase the number of pins available to the user by enabling A4~A7 connections in KURUMI.

I’d like to have holes for mounting another board (universal board, etc.). As it is now, when an Xbee is mounted, the Vcc of 4 holes (VCC, GND, RXD1, TXD1) and the SDI of 4 holes (SDI, SDO, SCLK, D3) cause interference.


Okamiya Yuuki

Thanks for the input. We’d like to keep the Lego holes, using the V cut. The motor drive is configured for single line movement, but, as I mentioned before, we’d like to enable it to turn, or combine servos to create a three-wheeled vehicle. We also think it needs to have as sound function. Unfortunately, this make require extending the length a little.



GR-SAKURA was Arduino-compliant so obtaining and controlling a shield was rather easy. But as there is no shield commercially available for GR-KURUMI, perhaps some suggestions of how to come up with a shield mechanism using available hardware could be provided here.

The hurdle for individuals to create their own boards has been considerably lowered.

Something like a circuit or component library?



Just want to make sure everyone has been reading the Usage Notes for the motor driver.



Thanks for the input! I did read the Usage Notes. The part about GND is particularly important. We are hoping that RS Compo’s Designspark will be used, allowing purchase parts with a BOM list. We will talk with Tessera. We conferred with them when designing KURUMI as well, but since they don’t use EAGLE design, I remember it was rather difficult.



I also added a motor to my gadget for Renesas Night.



Oh, that’s right, but I never got a chance to see it moving. How was the sensor value, even though there was no point of connection for power supply? Did it not move while reading the sensor?



Yes, it was moving (It runs at hyper speed so I am still working on adjustments), and it is able to read the sensor. However, it wouldn’t obey Xbee communications, maybe due to the high voltage or something. It responds when I tap it!



It could be because Xbee is wifi.



>It could be because Xbee is wifi.

When it is close the floor, it is easily susceptible to the multipath effect. Changing the antenna type or position might help.



I really want to create a sensor network with KURUMI!



Music to my ears! I fully understand that the Internet of Things (IoT) will bring us many interesting values through the correlated data of the combination of sensor data and connection to things either close by or fare away. The values will be even more critical when a time axis can be put to the raw data, such as acceleration of steps or temperature of cow fetus. Linking this to other things or to SNS, we will eventually have data with true dept, such as the ability to predict family budgets, illnesses, collapsing of tunnels, etc.

I would really love to see this make a huge difference, leading us to new lifestyles. I think new ideas of how to apply this coming to individuals or popping up during conversations, etc.



I think the Arduino has great libraries but it is not fantastic as an IC. KURUMI provides 3 serials and loads of memory.

But KURUMI beats Arduino hands down when it comes to low power consumption.

KURUMI spontaneously goes to power-saving mode, and can wake up spontaneously at specified periods. When Arduino is in its lowest power consumption state, I don’t believe there are any wakeup conditions other than an external interrupt (including RESET). And there isn’t a standard library for use in the power-saving mode.

This actually makes me concerned about peripheral power consumption when KURUMI I sin the low-power consumption mode. What is the sensor shield like in power-saving mode?


So, I would like to encourage the people at Renesas to keep promoting and improving KURUMI! Once you start using it is super handy!




Yes! I totally agree! The sensor node is so easy to use. In fact, I plan on using it in various areas of my own job from April!