# Pololu Blog

Welcome to the Pololu Blog, where we provide updates about what we and our customers are doing and thinking about. This blog used to be Pololu president Jan Malášek’s Engage Your Brain blog; you can view just those posts here.

# First new products under emergency operations - new servo wheels!

Posted by Jan on 7 May 2020

We are into May, and after almost 8 weeks of shutdowns and emergency operations, most of the world’s attention seems to be moving toward reopening and how to return to some semblance of normal, or at least longer-term sustainable operations. With no particular medical solution even on the horizon, it’s clear that we have a long way to go, and a city like Las Vegas is going to be hurt especially hard and for a long time by changes people will adopt until they are comfortable flying for fun again. Pololu has managed to hold up much better than I initially feared during the first week of mandated shutdowns, and I am especially grateful to all of our customers and staff members who have worked hard to get us this far.

It is with this backdrop of gratitude for making it this far while realizing we still have a long way to go that I am especially excited to announce our first new products released since the pandemic hit!

In all, we have eight new wheels for micro and standard sized servos. These are red and white versions of the four sizes we released in black back in January. Since we are operating with a minimum staff on site, we don’t have many actual pictures of the new wheels in action, so I will use the pictures with older black wheels for the rest of the post.

We have small, 40 mm and 60 mm sizes that are compatible with micro servo splines with 20 teeth and a 4.8 mm diameter and can be used with the following continuous rotation servos that we carry:

We have larger 70 mm and 90 mm sizes that are compatible with standard servo splines with 25 teeth and a 5.8 mm diameter and can be used with the following continuous rotation servos we carry:

If you plan on using the wheels with a servo not listed above, be sure to check your servo’s specifications for compatibility as servo splines are not standardized.

I was never especially fond of continuous-rotation servos, but there’s no denying that they’re often a quick and relatively simple way to get something moving, both from the electronics side (since the motor controller is built into the servo) and the software side. I am a fan of building your own unique robots, so I am happy we now have a range of size and color choices to give you more problem-solving options and variety in your robots.

Like many of our plastic products, these wheels were designed by us in Las Vegas and then injection molded in China. Since we already had the design and molds finished before we released the black versions, these new products are not the most new from a design perspective. We made the black ones first, and red and white were supposed to follow shortly after the Chinese New Year holiday. As we all got reminded, things don’t always go according to plan. And now, what should have been a minor new product has additional sentimental meaning as our first new product since the coronavirus upended our lives and a symbol of our determination to carry on.

We had been announcing new products along with introductory discounts for the last few years, and I wavered for a bit about doing extra discounts for these wheels. Shipping costs have gone up dramatically, and we’re trying to raise whatever money we can, so extra discounts are not the first thing I felt like doing. But the whole point is that we do want to celebrate at least a little! So, hooray for the continuation of the new product discount tradition:

## Other ways you can help (mostly copied from last post):

### Pay now, ship later

We have added a feature to our online checkout system to allow for orders to be placed with a “pay now, ship later” option that lets you authorize us to charge the payment for an order as soon as it comes in, possibly well ahead of when the order would actually ship. We started working on this feature at a time when we thought complete shutdown of our operations was imminent, when it might have been weeks or even months before we could reopen. As I wrote at the top of this update, we have been able to ship all orders, and I expect to continue shipping, but this option still allows us to prioritize shipments and reduce stress with orders that come in later in the day and can get shipped the next day. We have already received dozens of orders with this option selected, and it is also encouraging just to see that our customers are trying to help us out. Thank you to all of you who have selected that option!

### Order non-soldered versions of products, or the higher-stock versions

We offer a few of our products with some of the optional (but usually used) through-hole connectors soldered in. If you are able to solder, please consider ordering the non-soldered versions if there is plentiful stock of them. We do all of the through-hole soldering by hand, and most of our manual assemblers were older or otherwise in the higher-risk population for COVID-19, so they are not currently working here. And if you’re at home doing a non-critical project, now is a good time to do a little extra soldering, right?

On a related note, it’s a little bit easier for us if you order the item that has more stock. Each product page has links to relevant parametric comparison tables that can help you identify similar products that might have more available stock:

If your application could get by with either an item of which we have 300 in stock or one of which we have 12 units, please get the product that we have much more of. It’s probably a more popular version that we make more often, and it keeps the less popular version available for those who might really need it.

### Help each other on our forum

We have had to severely cut back on our technical support. If you are one those people with extra time on your hands now and are familiar with any of our products, please consider helping out our other customers on our forum.

### Ask others to help us out

If you know anybody that could afford to help us out, please let them know and ask them to contribute.

### Other suggestions and ideas

Part of the reason I have been going into more details in some areas of these updates is so you might be able to better give us advice about how we could make things better. Maybe you’re also working at a small business facing similar challenges, and you have some good suggestions. Maybe your uncle has a vacant building nearby. One suggestion I’ve heard repeatedly is about gift certificates, which we are looking into; if you know of particularly good ways of implementing that or things to be careful about, please let us know.

# COVID-19 impact update: still hanging on after three weeks

Posted by Jan on 6 April 2020

Monday, 13 April 2020 update – we got our PPP loan!

## After 3 weeks of emergency operations, we are still shipping all orders!

Today, April 6, marks the beginning of our fourth week of emergency operations. We are still hanging on, and it looks like we will be able to maintain operations similar to those of the past three weeks (i.e. continue shipping all orders with a minimal staff on site) at least through the end of April, by which point I hope some of the emergency loans we have applied for might start coming in.

## Thank you for your continued donations 🙏

We are very grateful for the many donations that continue to come in. As we trim our expenses, those donations become a larger fraction of what we need to get by. I know it’s asking so much for donations with no strings attached, and it means a great deal at a time when we are scrambling to make ends meet. To the many of you making us special proposals and suggestions, thank you and please keep them coming. We do not have the resources now to reply to them individually, but they do affect what we are considering offering and how we continue to operate.

If you can, please consider donating to help Pololu make it. We have set up item 2400 for donating in $1 increments. ## Please help reduce overwhelming workload (for those of us who can work) We are especially grateful for any routine orders that do not require special considerations. We are also happy to help with emergency orders involving efforts to fight the pandemic. For smaller, non-emergency inquiries, please understand that we are trying to maintain most of our usual operations with a much more limited staff while having to take on a lot of extra work (new HR issues for navigating layoffs vs. waiting for possible stimulus funds, coming up with new operating/safety procedures, rerouting incoming and outgoing packages among constantly changing rules for each country and carrier, etc.). Please help us reduce our workload by cutting back on non-critical inquiries. For regular orders, prices and stock are all on the web site. Tracking numbers are included in shipment confirmation emails. Invoices are available on the website when you log in. For technical support, please consider our forum. ## Emergency loan updates One of the most common questions or recommendations we get is about applying for emergency loans. We applied for an SBA economic injury disaster loan (EIDL) almost two weeks ago and followed up with the$10k advance application provided by the new CARES Act. We have been working with our bank all weekend to apply for the new Paycheck Protection Program loan, the applications for which have just started becoming available. My understanding is that the SBA is also scrambling as it is suddenly charged with processing more than 10x what they usually do over the whole year over the next several weeks. We received some confirmation about the EIDL loan being received but there’s been no visible progress on that, and in general, it’s difficult to know what to expect in terms of if, when, and how much we might be able to receive in emergency loans.

Given that uncertainty, it is especially urgent for us to cut costs where we can and to bring in whatever money we can to keep covering basic expenses. We are definitely hoping we qualify for some assistance and that it will come soon, so we are doing everything we can to keep all those applications moving forward while also trying to maintain operations independent of any guarantee of anything coming from that.

## Employee update

We received a few responses questioning our treatment of employees while asking for donations. They are far outnumbered by positive responses, and I suspect the negative responses come from people who have little appreciation of the realities of running a small business, especially amid this level of disruption. Nevertheless, I believe more people might be wondering about what we are doing, and I am proud of our response given the circumstances, so I would like to highlight what we have done so far.

Some of the responses questioned the “over half of our staff is unpaid in one way or another” phrasing. We had about 75 employees at the beginning of March, and over half of them are now either laid off, on unpaid leave, or volunteering to take a pay cut. This is just a basic reality of payroll being by far our biggest expense, and if people cannot come in to work and money stops coming in, there is nothing to pay them from. We are doing everything we can to keep Pololu in a viable state so that there is something for everyone to come back to in a few weeks or months.

Here is some of the rest of our response:

• Prior to any Nevada mandates, we began staggering our workbenches, improving sanitizing procedures, and set up some employees for working remotely.
• Within the first day of the Nevada governor’s emergency business closure declaration, we set up an emergency forum for all employees to be able to communicate without being on site. I have been posting there almost daily to keep everyone in the loop on our operations and outlook.
• We contacted all employees to make sure we had their contact information and understood their preferences about working (different people have different preferences based on their living arrangements, risk factors for COVID-19, etc.).
• We are maintaining health insurance and similar benefits for everyone who had them, including paying the employees’ portion for those who could not work and were out of paid time off (PTO). Some employees who were scheduled to begin getting coverage through Pololu are still getting added to our plans.
• We paid out remaining PTO to those laid off.
• We are maintaining PTO for those on unpaid leave and those still working.
• We paid full amounts due to those still able to work (excluding those volunteering for pay cuts).
• We are continuing safety assessments for on-site operations, including providing face masks for all on-site staff.
• We are working on improving remote connection and work capability.

## How you can help

### Landlord and building situation

After payroll, the building rent is our biggest expense and obligation, so I of course reached out to my landlord right away to see what their position was. Unfortunately, the building we are in was just sold in the last 6 months, so we do not have the long working history we had with the previous landlord. I am posting a little more detail here than I would normally be comfortable with, but we are in an extraordinary emergency and I am hearing the same questions and suggestions from multiple people, so I want to share this information because I believe it could be useful in getting us help and advice.

We are the only tenant in a building that is approximately 86,000 square feet. The building had been vacant, I think for years, after the previous economic downturn, and we moved in here at the end of 2011, taking part of the first floor. In 2013, the landlord received an offer for the second floor. It was a time when we were growing rapidly, and the building was not at all well set up for sharing with multiple tenants, so we made the owner an offer for the space and reached an agreement that was expensive but affordable for us and at a lower rate for the landlord than the competing offer but without the need to do any new construction. Over the next several years, we agreed to extensions in the lease and a gradual takeover of the remainder of the first floor, so that we would officially have the building to ourselves and the landlord could stop looking for other tenants to fill the remaining space.

In 2018, we negotiated a new extension of the lease. The building was still in its as-is state from 2009 or whenever the previous tenants moved out, and it was a particularly impractical floorplan based on the previous tenant’s operations. The landlord preferred putting some money into renovating the space and increasing our rent over keeping the rent at a bare minimum, and so even though our cost went up again, we were getting a more usable space with plenty of room for growth at still a decent total cost. The renovations took longer than expected and ran through most of 2019. Some kind of family change caused the landlord to unexpectedly have to sell the building, which got us to where we are today: with a new owner, in a building that is bigger than we need but well set up for us, and with what I think is a pretty good rate.

The new landlord thinks it’s an incredibly good rate and thinks the market rate (of course before this pandemic hit) should be closer to double what we are paying now. We have more than four more years left on our lease, and from his perspective, he might even prefer us to be out of the building. I suspect he has dozens or even more tenants from all over suddenly asking for reductions or notifying him that they won’t be able to make rent, and given his view of what we are paying relative to what the space is worth, we are going to be low on the list of tenants he wants to make special exceptions for. So for now, if we believe we can be back to full operation in the next few months and then resume the growth path we were on, it is very important for us not to give the landlord any pretext for evicting us. I realize some of what he told me might be for negotiation, but I believe he was generally up-front with me. (And I’ve been using the singular “owner” or “landlord” or “he” for the landlord in both the current and previous landlord cases, but really I am talking about my contacts for the ownership groups.)

I related the history of how we got here so that people who know more about this kind of thing might be able to give me better advice and so that people who look at some of the pictures I am posting don’t feel that we are wasting money on an extravagant work space. Yes, we could fit our current operations into a 50,000 square foot space. But building rent agreements can be quite long-term, and with the amount we have invested in equipment and improvements here, moving would be very expensive, even if we could find an appropriate space. And the value of our contract depends a lot on how things play out. If there is a long-term depression that we cannot survive, the contract is an anchor that will drag us down and potentially finish us. If things get better relatively quickly, the contract protects us and gives us stability, letting us operate at a relatively good rate, without having to interrupt everything to move.

I should also make sure it’s clear that I completely understand my landlord’s perspective (who of course has his own mortgages and employees to keep paying), and it’s good to know that he’s open to arrangements that could be mutually beneficial. Perhaps some more spaces will open up as other businesses close, and if we get forced to stop operating for an extended period of time, that interruption might also be a good time to move. For the time being, though, I think we just need to hang on for a few months, and if that is the case, we have to keep paying the full rent.

### Stimulus bill and SBA disaster loan

After days of trying on the overloaded SBA disaster loan website, we got our loan application submitted at 2:30AM on Tuesday. It’s not clear how long it will be before there is some progress with that or how much assistance we would qualify for.

We are also paying attention to the new stimulus bill that was just passed to see how it might apply to us. So far, it looks like it will be at least a few more weeks before the details get worked out to a level that we can do something with. The initial impression I am getting is that the way the support is structured, we might be incentivized to do things that would be bad for us if the support doesn’t pan out. For example, it is paramount for us to cut back on expenditures so that we have some cash to pay the most critical bills as long as possible. That includes laying off non-essential staff right away. Yet that might reduce or even eliminate some of the support we might qualify for.

There’s also a huge difference between getting a loan and that loan being forgiven. If the model for our collective response to the pandemic is that the government orders us to pause operations, then gives me money to distribute to my employees, I am happy to do my part in that arrangement. If, on the other hand, the proposal amounts to me personally being on the hook for the rest of my life to pay back a loan I took just to pay people that weren’t allowed to work, that’s not actually helping, and it would make more sense for those employees to just get paid directly from the unemployment aspects of the support bill.

We might also be facing a situation where the new support measures might encourage people who could be working to stay home and collect unemployment instead. So far, we have gotten by without pushing anyone who does not want to be here to be here. This will be a challenge for society in general as we all try to pause and then recover in this unprecedented situation. Many individuals want to work, but it might be better for the community if they don’t, and in compensating them for preventing them from working, we might be discouraging other people whom we do need to be working.

## Outlook and plan for now

The past two weeks of operation have made me optimistic that we could keep operating as we have for at least several more months. This past week was especially good because we had relative stability in how we operated, and it allowed us to spend a little time on getting ahead and start preparing for operating under these emergency measures for an extended period. A few engineers who had been working on production processes and were out the first week came in and started assessing our workflow with new distancing and isolation considerations. Having a lot of space is coming in handy, at least in terms of making it easier for people to work far apart from each other. We gathered in the same room once during the whole time, to select permanent spots in the break room:

(Those who have individual offices are encouraged to eat there, but in general, those are the people who are already home and connected remotely.)

We are also working on improving remote connection and working options where possible, including getting more computers and monitors to employees’ homes.

With the outlook unclear on how much government support we might get and when, it’s clear we need to transition to an operating mode where we can be largely self-sufficient financially without burning out before we get there. Here, the donations we have received have been tremendously helpful in buying us time to get back on our feet.

If you can, please consider donating to help Pololu make it. We have set up item 2400 for donating in $1 increments. ## Other ways you can help ### Pay now, ship later In the past week, we added a feature to our online checkout system to allow for orders to be placed with a “pay now, ship later” option that lets you authorize us to charge the payment for an order as soon as it comes in, possibly well ahead of when the order would actually ship. We started working on this feature at a time when we thought complete shutdown of our operations was imminent, when it might have been weeks or even months before we could reopen. As I wrote at the top of this update, we have been able to ship all orders, and I expect to continue shipping, but this option still allows us to prioritize shipments and reduce stress with orders that come in later in the day and can get shipped the next day. We have already received dozens of orders with this option selected, and it is also encouraging just to see that our customers are trying to help us out. Thank you to all of you who have selected that option! ### Order non-soldered versions of products, or the higher-stock versions We offer a few of our products with some of the optional (but usually used) through-hole connectors soldered in. If you are able to solder, please consider ordering the non-soldered versions if there is plentiful stock of them. We do all of the through-hole soldering by hand, and most of our manual assemblers were older or otherwise in the higher-risk population for COVID-19, so they are not currently working here. And if you’re at home doing a non-critical project, now is a good time to do a little extra soldering, right? On a related note, it’s a little bit easier for us if you order the item that has more stock. Going back to the screenshot I have at the beginning of this post, it’s easy to see our stock levels of similar products: If your application could get by with either an item of which we have 300 in stock or one of which we have 12 units, please get the product that we have much more of. It’s probably a more popular version that we make more often, and it keeps the less popular version available for those who might really need it. ### Help each other on our forum We have had to severely cut back on our technical support. If you are one those people with extra time on your hands now and are familiar with any of our products, please consider helping out our other customers on our forum. ### Ask others to help us out If you know anybody that could afford to help us out, please let them know and ask them to contribute. ### Other suggestions and ideas Part of the reason I went into more details in some areas is so you might be able to better give us advice about how we could make things better. Maybe you’re also working at a small business facing similar challenges, and you have some good suggestions. Maybe your uncle has a vacant building nearby. One suggestion I’ve heard repeatedly is about gift certificates, which we are looking into; if you know of particularly good ways of implementing that or things to be careful about, please let us know. ## Thank you all for your support. Stay safe and healthy, everybody! Please see new update posted Monday, 6 April 2020. # Coronavirus update - please help Pololu survive Posted by Jan on 22 March 2020 TL;DR: Pololu is hurting. Skeleton crew is shipping important products to customers fighting COVID-19 around the world. Most employees facing layoffs. Please donate to help us keep operating and spread the word. Donate here. Please see new update posted Sunday, 29 March 2020. The last time I posted on this blog was in November 2018, sixteen months ago. We have been very busy at Pololu since then, and there is so much good and positive to share about what we did in 2019 and so far in 2020. Unfortunately, what is compelling me to post this update and plea for help is the COVID-19 coronavirus pandemic that is engulfing our planet. Nevada, where we are located, was one of the earlier states to mandate sweeping reductions in activity, with the governor announcing on the night of Tuesday, March 17, that all nonessential businesses statewide were to shut down starting on Wednesday. We immediately began contacting all of our employees on Tuesday night not to come in the next morning while trying to plan for a shutdown of operations and looking for clarity about the extent to which the order applied to a company like Pololu. On Wednesday through Friday, we operated with a skeleton crew of around twenty of us, making sure we got orders out and received important incoming shipments. Pololu is probably not the kind of company that first comes to mind when you think of Las Vegas. We design, make, and sell thousands of products from our location just a few miles from the famous Strip. Here is our building when I was locking up Friday night, with the light from the Luxor pyramid lighting up the clouds: Inside, we have millions of dollars of equipment on which we have made millions of electronics boards that we have shipped all over the world. This is the newest of our three electronics production lines that we just finished setting up earlier this year, with machines that were all installed in 2018 and 2019: We have around two dozen pieces of big equipment, each one of which was a substantial undertaking just to install, with the electrical work alone costing tens of thousands of dollars in the most demanding cases. Here is the delivery of our latest laser cutter in November: We finally completed installation last month, and here is a picture I took for fun three weeks ago, with our first laser cutter from 2003 inside the new one: I post these pictures to help illustrate that an operation like ours takes a huge amount of effort to build up. I’ve been working on it for twenty years, and there are about 75 more people working on it with me now. We make and ship physical things, so we can’t just do this over a remote computer connection. And what do we make? For the most part, we make components, like motor controllers and sensors, that go into bigger systems. We do not know most of the applications our products go into, and we cannot disclose some of the more intriguing ones that we do know about. But we have specific confirmation that our products are being used around the world in this fight against the new coronavirus, from components in prototypes for ventilators to components in PCR equipment, including ones used for coronavirus testing. Are we essential, or essential enough to keep operating? With the changes we had already implemented prior to the governor’s order (for example, we suspended order pick-ups, so we are not open to the public), it seems clear that we are legally allowed to operate in accord with the clarifications the government has been issuing since Friday. Even before the ordered closures, we had done things like stagger our production work benches and spread out the tables in the break room: (FYI several groups of our employees live and carpool together, so a few chairs at one table seemed ok to have as an option. We’re probably going to spread out chairs more and go to one assigned table per employee tomorrow.) We are scrambling to stay in operation and to do it as safely and ethically as possible. The strain of trying to run this size of operation with two dozen people is enormous, especially while constantly having to prepare for being shut down externally and dealing with more and more uncertainties about components we need arriving. We are trying to get more people set up to work remotely, but I am posting these pictures to try to show how we cannot just run with remote workers. We are prioritizing shipping what was already made and making priority products that we know are for especially important customers. I don’t know how much longer we will be able to run. Maybe a few more days? Perhaps even fewer of us can get some especially critical orders out for longer, as long as the shipping companies keep shipping our packages. Things keep changing, so it’s hard to say. But if we are not shipping orders, or just a small fraction of the usual ones, money won’t be coming in. I have told my employees that they should not count on another paycheck beyond the one they just got on Friday. We will keep paying for health insurance for everyone as long as we can, and we are looking into the ramifications that would have for things like unemployment insurance. There is no way we can survive a shutdown of many weeks or even months. We tried to have redundancies in our operations, with as many backups as reasonable. We even have two compressors that we alternate each week, so that all our machines are not crippled if one of the compressors has an issue: But we just are not prepared for the level of shutdown we are facing. And so here I am, writing this post on Sunday night after coming up with a plan for tomorrow for my employees and writing to my landlord for help, begging anyone who reads this to help. I know many people and small businesses everywhere are hurting now. I am sure everyone who has put their life into their business feels like theirs is special. We have the facility and the machines and the people who know how to churn out millions of units of hundreds of designs that people around the world use. We have an awesome team. We just need the money to survive until we can start running again. We are of course looking everywhere for help, and will be applying for whatever disaster relief is available as it becomes available. This is an unprecedented time for us, as I know it is for everyone. I know it is so much to ask for money with no strings attached, especially at a time like this, but that is what will most let us pay our obligations and our employees without diverting resources into extra accounting and agreements. We have set up an emergency product on our website that will allow anyone to donate money to Pololu. You can use item 2400 to donate in$1 increments. This is still part of our regular website, so checkout will ask you for a shipping address, but there is now a “no shipment” option on the next step of checkout. We’ll work on making it smoother.

If you cannot personally donate, perhaps you know of someone who could. Maybe it’s someone who likes making things and wants to support a company like Pololu. Maybe it’s someone in Nevada who knows nothing about robotics but would like to support diversification of our economy. I threw this post together quickly and marketing was never my strong suit, but I will be updating our pages with more information about why Pololu is especially worthy of your support.

We (the off-site portion of the team!) will also be working on a feature to let you order non-critical items that we would ship once we can resume operations but with permission to charge your credit cards immediately so that we can keep our employees paid. (Update 3/25/20: This feature is now available. You can find the option during step 3 of checkout.)

If you got this far, thank you for your consideration and for any help you can give. Stay safe and try to be kind and useful to those around you.

Please see new update posted Sunday, 29 March 2020.

# Empty Vessels: a performance of robots, cellos, and artificial intelligence

Posted by Emily on 28 February 2020

Artist David Gardener contacted us recently to share his work, Empty Vessels (seen in the above video), an immersive audio visual installation that explores the connection between machines, data, and their environment. The piece features three cellos played by custom built robotic structures that perform music composed in real time. It premiered in November 2019 at the Society for Arts and Technology in Montreal, where it performed for sold out audiences for two weeks! David was kind enough to answer our questions about the piece and allow us to share his answers along with some more footage and pictures with you below:

How long did you work on the piece?

The project started as an idea by myself (David Gardener) and Greg Debicki about a year ago. It remained an idea for most of the year until we were approached by the Society for Arts and Technology in Montreal (SAT) for help funding the project, where we could work on the project as artists in residence. At the end of the residency (in November) we would also premiere the show. This gave the project a very fast timeline taking just two and a half months from concept to presentation for two weeks of shows. I think it is probably the quickest timeline I have ever worked to, having to design, engineer & build the whole project.

Can you tell us which products of ours you used and how they were used in your project?

For the project I used the following components from Pololu:

These were used to drive linear slides that moved the note sliders up and down the fingerboard. The reason for using this method was because I am a cellist myself, and the ability to slide between notes is really important in the sound of the cello. Unlike a guitar, there are no frets on a cello’s fingerboard, so the note sliders have to move to very accurate positions on the fingerboard to make sure that the notes are nicely in tune. On startup the motors would all drive the sliders to a home position using a limit switch. From there they would move to the different notes just by driving the motors to pre-defined positions. I decided to use a slider per string on each cello to maximise the amount of notes that could be played simultaneously, meaning they could play 12 note chords, or fast melody lines by splitting the melody across the 3 cellos.

Did you design the slider systems for the fingerboards? It looks like some of the parts might be 3D printed; are the design files available anywhere?

Yes, I designed the whole robotic system from scratch. The cello is such a beautiful instrument in both design and sound. However it is designed specifically for a human body, none of the strings are parallel or in the same plane even, they all diverge towards the bridge. I didn’t want to change the actual instrument in any way for this project. This complicated the build a lot! On top of that, no two instruments are the same, so I had to make sure that the parts could be adjusted in the different planes depending on the instrument they were attached to. Another difficulty is at the top end of the finger board the strings are very close together meaning the sliders all had to be very thin so as not to collide with each other. In the end all these considerations led me to the decision that I would 3D print all the parts. With such a short build timeline, this meant I could design and print revisions of all the parts much quicker than if I was making all the parts by hand in the workshop.

The designs for the parts are not available at the moment as they are very much working prototypes! I plan to upload them for anyone that wants to see them at a stage in the future that I am happy with them.

Can you tell us what your motor control setup is? (What motor drivers are you using, how are you processing the encoders, how are you coordinating all the movement, etc.?)

So I think I answered this in question 2. But a more general overview of the working of the cellos is – The main brain of the three cellos is the software MAX MSP (running on a PC). This would send position data over serial to an Arduino which then told the RoboClaws the next position to send the motors to. The RoboClaws were running in closed loop mode so they were dealing with the encoders directly.

We noticed you have some fans pointed at the upper bank of motors on each cello. Are the motors or controllers overheating, or is that to protect the cellos from getting too warm?

That is funny. Yes, originally I was using your 4.4:1 gear ratio 12 V motors as I really wanted the note sliders to be whizzing up and down the fingerboards like a cello maestro. But after burning out some of the motors by driving them too hard, I decided to switch to the next gear ratio down (and actually even they were getting hot). But by this point I had already locked off the design and ordered all the motors as the opening night for the piece was in three weeks. So to make sure I didn’t lose any more motors, I added some forced air cooling (just a silent fan sat on a bar stool pointed at the motors of each cello)… it added a slight bit of rock ‘n’ roll to the show.

Can you give us some details about how the music is generated?

So the project is headed towards having a fully artificially intelligent score where the music is generated on the spot and then played. The project is designed to also play in a museum environment where it will sit and play for its audience forever evolving music, with the intensity of the compositions controlled by the number of people it is playing to. However, it is currently in a more generative state where it will play music based on a set of musical rules from which it generates the music. This is where my collaborator Greg came into the project, developing patches in MAX MSP that generate the compositions and then work out which string on which cello to send each note to.

Is the piece on exhibit anywhere currently, or are there any planned exhibits coming up?

The piece was shown for a week at the SAT at the end of last year, but it was almost totally sold out so an extra week was added straight after that. The cellos are now back in my studio, where they will be upgraded. They are scheduled for another two weeks of shows at the SAT from March 24th 2020. There are some other shows in Montreal where it will be shown as part of some electronic music and tech festivals (unannounced as of right now). It is then planned for a European tour late summer 2020. It is best to keep track of the dates from my Instagram, @montreal_life_support.

Do you have a website or any social media channels where people can follow your work?

Instagram is probably the best. These are the handles:

Other than that I will be releasing a making-of style video documenting the build in the coming weeks on the YouTube channel.

Thanks so much to David for sharing your work with us and answering all our questions. For readers in the Montreal area near the end of March/beginning of April, visit the Society for Arts and Technology’s website for showtime and ticket information.

# New products: Pololu Wheels for Micro and Standard Servos

Posted by Emily on 22 January 2020
Tags: new products

We are thrilled to announce the release of our wheels for micro and standard sized servos. These wheels are similar to our wheels for 3mm D shafts and consist of a durable ABS hub with a silicone tire. They are currently available in 40, 60, 70, and 90 mm diameter options. All but the 40 mm size feature mounting holes that are compatible with various versions of our universal mounting hubs and slots in the spokes that allow additional accessories to be mounted to the wheel such as decorations or parts of an encoder system.

The 40 mm and 60 mm sizes are compatible with micro servo splines with 20 teeth and a 4.8 mm diameter and can be used with the following continuous rotation servos that we carry:

The 70 mm and 90 mm sizes are compatible with standard servo splines with 25 teeth and a 5.8 mm diameter and can be used with the following continuous rotation servos that we carry:

If you plan on using the wheels with a servo not listed above, be sure to check your servo’s specifications for compatibility as servo splines are not standardized for particular sized servos.

These wheels, like many of our plastic parts, are designed by us at our Las Vegas facility and then injection molded in China. Usually, we ship bulkier parts made overseas by boat, which can take several months to get here. We were so excited about these, though, that we couldn’t wait that long! So, we had a small amount shipped by air to make them available as soon as possible. This means the initial stock of these is limited, and while we’ll have more coming by boat, the upcoming Chinese New Year will delay that even more than usual. So if you don’t want to miss out on these initial units, order yours soon!

## Introductory special

As usual, we are offering an extra introductory special discount on these wheels, to help share in our celebration of releasing new products. The first hundred customers to use coupon code SERVOWHEELS can get 22% off up to 3 pairs of each size!

# New products: 24V 37D Metal Gearmotors

Posted by Emily on 17 January 2020

We are excited to share that we have expanded our line of 37D Metal Gearmotors to include 24 V options. These brushed DC gearmotors are the largest and most powerful we carry, measuring 37 mm (1.46″) in diameter. They are available in gear ratios ranging from 6.3:1 to 150:1 and with or without integrated 64 CPR quadrature encoders on the motor shafts. The 12 V and 24 V motors offer approximately the same performance at their respective nominal voltages, with the 24 V motor drawing half the current of the 12 V motor. The table below summarizes all of the options we now have available. Please see our newest revision of the 37D metal gearmotor datasheet (2MB pdf) for the full specifications and performance graphs for all the options.

Rated
Voltage
Stall
Current
Current
(RPM)
Extrapolated
Stall Torque
Max Power
(W)

Without Encoder

With Encoder
(kg ⋅ cm) (oz ⋅ in)
12 V 5.5 A 0.2 A 1:1 (no gearbox) 10,000 0.5 7 item #4750
6.3:1 1600 3.0 42 12 item #4747 item #4757
10:1 1000 4.9 68 12 item #4748 item #4758
19:1 530 8.5 120 12 item #4741 item #4751
30:1 330 14 190 12 item #4742 item #4752
50:1 200 21 290 10 item #4743 item #4753
70:1 150 27 380 10* item #4744 item #4754
100:1 100 34 470 8* item #4745 item #4755
131:1 76 45 630 6* item #4746 item #4756
150:1 67 49 680 6* item #2829 item #2828
24 V 3 A 0.1 A 1:1 (no gearbox) 10,000 0.55 8 item #4690
6.3:1 1600 3.5 49 14 item #4688 item #4698
10:1 1000 5.5 76 14 item #4689 item #4699
19:1 530 9.5 130 13 item #4681 item #4691
30:1 330 15 210 13 item #4682 item #4692
50:1 200 23 320 12 item #4683 item #4693
70:1 140 31 430 10* item #4684 item #4694
100:1 100 39 540 8* item #4685 item #4695
131:1 79 47 650 6* item #4686 item #4696
150:1 68 56 780 6* item #4687 item #4697
* Output power for these units is constrained by gearbox load limits; spec provided is output power at max recommended load of 10 kg⋅cm.

Note: The listed stall torques and currents are theoretical extrapolations; units will typically stall well before these points as the motors heat up. Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. The recommended upper limit for continuously applied loads is 10 kg-cm (150 oz-in), and the recommended upper limit for instantaneous torque is 25 kg-cm (350 oz-in). Stalls can also result in rapid (potentially on the order of seconds) thermal damage to the motor windings and brushes; a general recommendation for brushed DC motor operation is 25% or less of the stall current.

# New products: D36V50Fx Step-Down Voltage Regulators

Posted by Kevin on 15 January 2020
Tags: new products

We have a new set of regulators to announce: the D36V50Fx family of step-down voltage regulators. Measuring a compact 1″ × 1″, these regulators support input voltages up to 50 V and can typically deliver around 5 A of current, although some versions can output much more under certain conditions.

The family consists of six fixed output voltage versions between 3.3 V and 12 V:

We can also manufacture a customized version for you here in our Las Vegas facility. For example, we could make regulators with a different output voltage that your project needs, or we could replace the 40 V reverse voltage protection MOSFET with a 20 V one for slightly improved efficiency if your input voltage will always be lower than 20 V. If you are interested in customization, please contact us us for more information.

## Comparison to other regulators

The D36V50Fx regulators are larger and more powerful counterparts to the D36V28Fx family we introduced last year, with the same input voltage ranges and mostly similar characteristics. What distinguishes the two families in performance is that the D36V50Fx regulators can provide roughly double the output current! (At the high end of the input voltage range, the difference is generally less dramatic.)

And since many of our most popular regulators are 5 V modules, here is a graph comparing the new D36V50F5 (in blue) with two of our older high-power regulators, the D24V90F5 and the D24V50F5:

## Introductory special

As usual, we are offering an extra introductory special discount on these new regulators, to help share in our celebration of releasing a new product. The first hundred customers to use coupon code D36V50FXINTRO can get up to 3 units of each version for just \$11.95 each!

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