CwhatIcanDo.com allows everyone to view the results of Project Creators.

For experimenters: A place to organize your project in steps (as many as you need) using pictures or videos to explain to others "how-to" create this project.

For professionals: Another place to add videos or pictures of your finished work, so people who are looking for your company`s goods or services can see examples of your work. Sell your projects via kits, books, instructions, etc..

For either, a set of development tools created to permit you to show in step by step form how to do it yourself, or how a process or procedure is done.

So, whether you are building street cred for an addition to your resume, or trying to sell parts kits for a home built scooter or birdhouse. You can give others the chance to buy a kit of parts from you, the creator.

In fact, thats one of the differences between CwhatIcanDo and other do it yourself or weekend project websites. You, as a creator of a project can make money by selling your project parts through a distributor with which CwhatIcanDo has agreements.

Thus when CwhatIcanDo refers someone to a parts source, simply by clicking a link this website makes a commission from the sale which CwhatIcanDo splits with the creator.

You got it. Showing off your project on CwhatIcanDo gives you a chance, not just for glory, but for Money$$$$$!

To Create A New C What I Can Do Project.

* SignUp for Creator Account. It`s Free!

* Login with your new User ID and Password. Now when you Click Creator`s Tools, you will be led to your creator`s account.

* Create Your First Project. Just for an experiment. You can delete it from your Creator`s Tool any time.

When it goes, it goes like this... Forward motion until the feeler touches something which reverses the motor. When it backs up, the motor has a clutch that causes one leg to not move in reverse. The net effect is when the bug backs up, it turns, thus a simple object avoidance algorithm runs without a control computer to make it happen. I almost forgot, there is a clapper in the HexBug. Yeah, just clap and it reverses, whether it hits something or not. I forgot to show that in the video.

This is my version of (at least) the base of an RFL upright robot. It works pretty well, but I can't go much further until I get my hands on one of those RFL Football Robots.

Then, I'm going to want to make my RFL Robot Base into the most powerful line backer or maybe Center in the RFL... Geez, maybe the "Super Bowl?"

Wait a minute. They use like a 9-Volt battery pack and a fancy gearmotor on each wheel...

OK then. This bot will make a nice coach bot, or cheerBot... Maybe just half-time entertainment?

Geez.

DogBot is my first robotic dog project.

I was inspired by a guy who was building a Robot "watch dog." His dogbot was a little different than mine. I guess his junkbox had different items than mine.

Anyway, his dogbot was great, so it inspired me to build my own. His dogbot had 4-wheel drive, mine two-wheel plus steering.

I'd recommend 4 Wheel Drive so the dog can shift quickly from one direction to another. With steering control, poor dogBot has to backup to do a 180.

Your programming life will be so much easier, your batteries will last longer and you can turn your dog more like a real dog. It can even chase it's own tail.

But, unlike a real dog, a recharger is the only food this dog will need.

Take a PicAxe brain, add an infrared "whisker" and a motor controller, transplant to an existing wall follower robot and you have:

"CRAZY Mouse Bot on Steroids!"

For the issues and tricks, here`s what I did:

* Mount the Power Transistors right down at the motors, if you bend them like wings, you can connect to their bases and feed power directly from the on/off switch
* With the batteries I`m using AA-1700 mah, you have to turn off brown out protection to allow the processor to go under 3 and 1/2 volts or so, you also need to keep the batteries fresh
* The four battery clip is a little large and collides with the top of the back, shim it in the back so it leans forward, that works.

That`s it!!

Have fun programming your MouseBot!!!

This is a project I call the buggyBot, not because it won't do what you ask it, but because I want to build a little buggy that runs around the room and gets itself into trouble...

I came up with the idea of using wire robot frames by looking at some of the creative bodies people built out of junk and wires, and extra components. I could see the advantages, you could change the whole body by grabbing and twisting.

I thought the process could be used for more "traditional" bot bodies. I also had a couple of Toshiba 8080 (Yeh, I know what you're thinking) H Bridges I wanted to play with. This is the Wire Body Bot I created.

This is a how-to video for building an L298 Dual H-Bridge Motor Controller. I can`t wait to drive a robot with this controller.

This is a higher current model than the TI version used in the motor drivers that come with the picAxe evaluation boards.

The drivers can handle a couple of Amps each so this thing is fairly healthy. The issue is the strange pinout. You are almost assuredly stuck with having to create a PC board, and that was more work than I cared to create for myself.

So I bought the kit and put it together in a couple of hours. It worked fine and now I`m ready to put it to use.

How to convert a standard incandescent flashlight to an LED based flashlight. Everyone knows the new high-light output LED's are the rage in small hand-held battery powered flashlights.

It used to cost a lot of money to get access to high-light output LED's, but they have become cheaper and are now available for less than a dollar. In this example project the LED cost 25 Cents! That's a pretty reasonable price for a new flashlight.

The advantage of LED, is the output of light without all the heat generated by the incandescent (hot wire in a vacuum.) That means less power used and flashlight batteries that hit the landfill less often. Using a combination of rechargeable batteries and incandescent replacements means you'll probably never see the landfill, since the low power drain will mean you'll rarely even have to recharge your batteries as often.

So this is a green project too! Go green, have some fun!

From thanking the Post Office guy for delivering the shipping box, to operating the robot! It's all here in this video.

1. Unpacking... Careful with all the packing peanuts.

2. Opening the box... You get a nice box with plenty of accessories. You can see the bot through a transparent cover. Not too flashy. They aren't marketing all over me with it. No, it's clean and simple and, if you've been watching the videos only and haven't seen one in person yet, be prepared to be happy.

3. Charge the battery. Instructions are actually sketchy about this. Let me be clear: It ships with niCads - give 'em an overnight charge, drain thoroughly, the usual niCad care and keeping.

4. Turn on the console, it should ship set up to control your bot.

5. Turn on the Bot. After announcing itself as "RFL" in a booming voice, it will reset it's throwing arm. (Watch out, it slams down pretty hard, and can pinch!)

6. In a moment, the Bot's Helmet should light up. When it does, it means the data is flowing to and from the bot.

7. Drive it!

*. A tip... There are extensions for the wheels to allow it to back up on carpets and rougher surfaces, like my back deck. Think of them as training wheels and put them on while your battery pack is charging. It will be easier to drive the bot. Fewer nasty falls when backing up on rough surfaces.

See next video for driving with extensions...

I`m calling this robot basics, but I`m leaning to more like a minimum "robot."

Introduce a couple motors, a switch, and some bumpers.

Add some delays, etc by using a timer control. Thus it can crawl backwards for example, for 1/2 second then start going forward again. Then you can power on a right or left turn on going forward.

If you put a listing and it leaves out some, then you have exceeded the limits for an input box and you will need to split...

There`s a bug. If you use pre for format control, the pre shows in the listing for the project. For now, skip the insertion of the <pre>uses direct format</pre>.

This is just a placeHolder for a project with "multi" in it's name. Thus it will display as a SiteCategory (Multi Media).

With a single motor and a single servo, you end up with an interesting configuration. Im playing around with an idea to create a ball-bot, if you will. The ball robot would be driven by a single drive wheel which is turnable. Thus, from inside a large ball, you could make a round ball of a robot. That idea intrigued me!!!

Put a single drive motor on the end of a servo, then use that inside a ball.

I couldnt resist playing with the idea. This is the result of the combination. Since a two-rear wheel stabilizes the single drive wheel we test the idea with a Tricycle robot!

Both motor speed and direction are easily controlled using the picAxe 14m. The speed and direction motor drives most small DC electric motors up to 1A stall current. It uses the Toshiba TA 8080K to drive the motor. This is a chance to exercise the capabilities of the 8080. Yes, the 8080 which gives some of us flashbacks to the early microprocessor days!

Steering is controlled by using a servo. In the buggy bot, this servo turns steerable front wheels. While you can also use the servo to steer the drive wheels as in the tricycle robot base project.

What is a picAxe?

A picAxe is a pic microcontroller (In this case a PIC16F684.) with a built-in BASIC Language Interpreter. Yes, it eats up a bit of memory and can do only a limited number of things. But you cannot beat a pixAxe for experimenting and playing around. If you use them correctly, they can serve well. But you may need to dedicate the chip. For example, dogBot used a picAxe 14m just like this project. It could drive Servos, OR Drive Electronic Motor Controllers. Trying to get it to do both is pushing the capabilities.

When you need to use more of the chips capabilities, you get a bigger chip, or you program the PIC16F684 in a compiled language instead of as a picAxe.

picAxe 8m`s are other examples, while the chip itself can decode IR signals, the limitations on number of pins restrict it from many applications. An m8 can control a motor, but little else. The 14m in this project uses all the available outputs and could still use more. Achieve complexity by using more than one chip. (Or go straight to assembly language or C compiler which gives you much more memory, but makes programming difficult.)

This video describes the first experience operating the WowWee! Tri-Bot. From out of the box, how it works, how to use it.

Of course the first, arguably the most important instruction is how to turn the robot volume down. This little red robot will drive you crazy as it rolls around your house. The usual WowWee robot, you can program movements and play 'em back. You can manually control the bot, it is really good at spinning in place, but it will move forward, back left and right.

The most fun happens when you set the Tri Bot "free" to roam on it's own. Just hit the brain button and it moves around avoiding, and occasionally engaging obstacles.

The downside, the tri drive falls over a lot when it engages a wall. The object detector is located high on the bot, so it runs into smaller things a lot, without even knowing about 'em.

I'll let you judge how much fun you may have with the robot. I have my eye on the tri-bot's drive motors and those multi-directional wheels!

Describes how to "build one of these" yourself. Pretty much is a step-by-step guide to build your own track drive robot.

It is pretty simple and relatively cheap and actually kind of a fun way to become familiar with Robots and Robotics in general.

It isn`t long after getting your first robot, you start to wish that little wheeled bot could climb over things in a relentless forward motion - - Like a Tank!

Even though the old timers told me I didn`t want the hassles of a track-drive robot, I knew it wasn`t true. I wanted one! I wanted it simple and cheap and programmable for fun!

SimpleBot the 5 Minutes to Build Robot. This is `the bot` for experimenters who are anxious to make their first robot and get it running. It`s held together with tape, so you can take it apart and experiment.

The example Simple Bot uses a couple of gearMotors with wheels, battery pack, etc..

One of any starting roboticist`s issues is making the robot base. In this case, the robot`s base is made out of the bodies of the gearMotors themselves. Simply arranging the gearMotors, then taping them together allows the experimental roboticist to take the starter bot apart and put it back together again.

NOTE: Don`t Forget to put a picAxe 08m chip. In some cases, depending on where you get your picAxe motor controller chip, you will have to replace the 08 with 08m, or write your own code... If pin3 high there`s an object... and check before you make the motors run!

What about Really separating Creators from just commentors, lookie lu's etc...

They can work together, but the Creators may need a little quality control... Plus this gives things the ear marks of a new competitive engine where ppl come together around Ideas... Maybe CwhatIdid.com?

---------------------------
Maybe sooner

- If someone is creating a parts list, they need to be able to grab things from other parts lists... The multiMedia "holder" page (creator) needs to offer an appropriate filler when a project is created.

Maybe it's contextual, if you sign in as Creator from the Site Category of Robots, you get Robotic fillers (and conceivably, backgrounds and stuff as a default...

- Parts list components should offer "sponsored" parts only. Say like SparkFun...

"New since your last visit" add this...

Hello, Dr Zoidberg again. I was trying to figure out what to do with the large quantity of clamshells I have accumulated since taken residence in the "Mother of Perl" software factory. After hours i get hungry and it's amazing how big the piles of clam shells I am creating.

This is a pretty complex site when you decide to become a creator. There are so many things you can do with the creator tools and we hope they get even nicer with more capabilities over time and use with feedback.

Pictured here is the HOME PAGE... You can Xpand the menu and look around at categories, creators, keywords, or by how many visitors.

For the tour, we will look at all the pages you need to deal with to create your own project and feature it on CwhatIcanDo.

Installation instructions for a 4 section in-ground batting cage from PracticeSports.com.

There are a variety of different "packages" available. These are available at a relatively low-cost by buying sectioned kits.

Hello. This is WeRbots, with the robot videos, you know another robot Freak...

I built this website mainly to have a place where I and my friends, amateur and professional robot builders could show off our stuff.

Though this isn`t exactly a step-by-step project you can build, it is fun because, for me at least, it is a way to record my robo-nutiness for all posterity. At least as long as there is a You Tube!

This is a collection of the commercial robots I bought. Some I bought to learn, like the Avoider, others I bought to Mod, like RoboQuad, whatever the reason, these are some of the bots I bought trying to make my way in the world of DIY robots.

Enjoy the Videos!

The low-cost picAxe Motor Controller allows you to build a universal motor control for Robots.

Just mount the IR detector right on the board. Then you can mount the whole thing on an R/C car or junker robot and wham! You are in business!


You need an 8m picAxe chip in the controller. Most are advertised with an 8m chip, although I have found them with only a picAxe 8 pin chip. There is no interrupt in the 8 pin chip, so you will need the 8m to make this design work.

Why do this? You can have a controller that you can move around. It is cheap and easy to create the universal board by mounting the IR detector directly on the PC board.


Give some examples of alternatives - Like using the TA8080.

Get Software...

Yes, you can build your own muter. I built one in a button, but the form factor is not the biggest part of the project.

This project uses the picAxe microcontroller chip because it has built in Infrared Remote Control codes for Sony TV`s. I have a Sony. I simply put the already built-in functions in the picAxe to work.

I was careful about current drain. I could have made the Infrared light more powerful and increased the range, but I`m usually sitting by the fireplace on a rainy winter night when on comes a commercial!

The commercials are hyper modulated, there is no dynamic range and the result is like listening to an orchestra of square-waves. And those "Gotta Have One Now" pitches is terrible enough at any sound level. But definitely offensive to your auditory circuits.

Here is a robot project that uses the picaxe 08m with an infared module to control a small robot.

It uses off the shelf parts and a motor driver board.

I build robots. Little electromechanical machines that roll around the floor, seek light, avoid objects. Stuff like that.

I also run a little kid`s website called cybercritters. So I decided the kids might like a robot to drive around. If they like it enough I can expand it to run in 2 1/2 D, or avoid objects, or make it into an avoidance race, or whatever strikes my fancy.

I thought it would be fun to share how I put the little robot together using Flash. I use the old Macromedia Flash 8, I just can`t spring for the loot right now.

So here`s the inside scoop on how I built a robot that is virtual, and you can play with it for free on the web.

I hope this inspires you to get you to fire up flash and improve this game, in fact, learn how to make games. Become a great programmer. Just get inspired, here at CwhatIcanDo.

Add a 100MHz 32 channel Logic Analyzer to your workbench to debug PWM signals, SPI protocol, or any digital logic. Project homepage is http://www.gadgetfactory.net/gf/project/lax/.

The Open Source design of the Software and Hardware allows anyone to make it their own.

Based on FPGA technology which allows high speed sampling.

One 555 timer and a couple of parts and you get a balancing robot base.

I`d love to take credit for this project, but the credit for making a balancing robot goes to roboanalogtom (Tom Jenner) at You Tube.

Frankly, even though I didn`t do the work, I knew there were others who are interested in such things. Like the upright RFL robot base project.

The video tells it all and maybe when roboanalogtom checks his links and finds CwhatIcanDo users are viewing his video, maybe he`ll come here and share schematics or better still, show his latest version.

qko

It`s been a while since I created a new project for Cwhat I can Do, so here goes.

I obtained a Motorola Droid. (They finally got on Verizon - The only network that covers the Santa Cruz Mountains.)

But I`m a robot guy? So what Have I got in Mind for a Phone that calls itself a Robot? Well, of course I`ve got an idea or two...

I`ve been considering using ATX mini motherboards, web books, you name it. So along comes Droid. The more I read about it, the more it seems like this is something I could use to control a Robot.

And maybe, just maybe, could become the central controller for my Dream Robot? High Hopes for this platform, and now that I have one, I am not disappointed.

henryMLYV

Build yourself a fun obstacle avoiding robot that drives around all by itself, exploring new territories and managing to keep itself out of trouble.

This project uses just the base in a very simple robot which runs around. It proves how nice the little Rumble Bots work as a Robot Base.

You can make yours look prettier by incorporating the old head into the design. See http://www.dinofab.com/rumblebot.html for his Rumble Bot conversions. He`s done a few more than I have.

Convert an old broken down Rumble Bot into a wandering autonomous robot.

It`s cheap and really easy to make an old Rumble Bot into a new, more self oriented obstacle avoiding Robot.

Rumble Bot = 5 - 30 bucks (broken ones are fine, you are going to "gut" the electronics anyway.

picAxe Motor Control PC board (comes with picAxe 08 chip) < $16 bucks

picAxe 08m chip (less than 4 bucks)

IR "Eyes": around $12 dollars, works in every light level, impervious to false triggers.

A 0.22 uf capacitor on the output of the above to keep it from jittering the interrupt pin...

My total cost = $35 USD... It`s an easy way (programmed in BASIC) and cheap way to learn about autonomous robots.

I picked up one of these without a controller for $5 bucks. After searching around, I found it. It`s the Morphibian Land Shark. One of these run`s like a real scatter bug!

First thing was to pull it apart and put one of those 08m picAxe chips in it with an IR Sensor. The results were impressive.

When I first took it apart, I noticed the gears were neatly sealed and there was a lot of foam pieces inside the motor cavity. I thought it was to make it run more quietly, but it was to make it float. Now I`m thinking this might be an optimal run around the house and yard robot.

This could be the body that works just right for Robo Dog II ! Woo Hoo. And you can still buy these things, not like the rumble bots, which are very hard to get your hands on.

It`s a robotic, sun-powered, holographic scare crow. You can build one yourself. I used pieces of bamboo to make a cross piece to hold the motor and solar cell.

You can build it in a weekend in a couple of hours. Just follow the video and you`ll have the most up to date thoroughly modern scare crow ever!

it`s cool

This Pencil Could Do Your Homework For You... Don`t Even Put Your Hand On It!

Low-Cost, super simple robot you can build yourself in a weekend.

This robot was inspired by my original attempts to build a "dog" bot.

What makes this neat is that it is simple to build AND it is expandable. Expanding is done by changing to a larger processor.

I`m building another version of the little control board using the picAxe 18x just to give myself more program space to make the thing behave simply.

.

Bumps and swivels I`ve run into while trying to build small robots.

A Bump is something that stops further forward exploration, a swivel is something that helps me ease around the current issue.

From the bumps, I learn things not to do. I bumped into problems.

From the swivels, I deal with things that make bot building easier.

Here`s one for us hackers and modders! Linux powered robot with 2.4 gHz two-way radio controller. Video from the camera on deck of the robot feeds back to the screen on the controller.

This is the same radio that provides the smooth and great control for the RFL robot. Not as fancy, but there`s no video feedback on the RFL bot. And, there`s somewhat easier to program (don`t need a pic programmer) device on board. It has it`s own C compiler You simply use the gnu compiler with a library for the ARM-9 chip.

Both the bot and the controller use ARM-9 chips, both have USB ports. Not much is known yet, the builders haven`t published everything, like schematics and all yet, but it`s comin` so they promise.

I was able to get one of these for less than a hundred bucks. Inspection of the box and any mods will come later. Another site is doing a breakdown and take apart and another has done something like I`ve done here.

The big question is "what about tilting the video camera?" Other bots are a little crude at this, but from my cursory inspection, a little arm can come out through the clear plastic cover to an awaiting servo arm. If all goes well I can program one of the gpio`s (right there on the pc board, all shiny, and waiting to be soldered to). The gpio (I hope) will provide the servo drive signal, and if so, then maybe I use a spare switch on the controller to gradually run the camera up and down.

Being able to change camera elevation is important to bot builders... It`s my goal for hacking into this bot.

What else is needed? Lot`s of IR to help it not bump into things, when you are looking elsewhere. And some edge detectors facing down to keep you from accidentally driving down the stairs. Just basic stuff - should be easy to add. How easy? We will hopefully hear from the manufacturer soon with details, meanwhile, I can dig around a bit myself. After all, I yam a modder and a hacker!

I have obtained a pixAxe 18m2 to replace an 18x I was using in a project. The "m2" is the bees-knees for the things I am putting it through.

HOT STUFF and COLD STUFF

Hot list first, it`s the longest. It`s multi-tasking! I couldn`t believe it. No more timer problems (so far) driving pwm timers and servo timing. It seems much nicer now. You can run four tasks at a time and have complete programmatic task control.

And still you have interrupts! What a joy. Right now I`m playing around with a controller that`s sort of a half breed using pwm and electronic motor control to drive a two-wheeled bot.

Where the fun comes in now is fun with distance, since I can read on one of the many ADC`s from an IR rangefinder. Not only can I look for objects, I can react to them differently as I check things out in the area. Thanks for the multiprocessing.

And, to make that even better, you can bump the 4mHz / 8mHz timing up as high as 32 mHz, although you lose the correct timing for servos if you go above 16mHz :-) ROFL

Thus each of the 4 processes can rip along like they think they are running on 8mHz chips... Again, a winner!

Legs are replaced by port.pin dot annotation. So no pin/leg issues for my muddled old brain.

I haven`t tried `em yet, but there are capacitive touch inputs, fancy capacitive touch sensors like on an I-something. I will try them.

I have tried the all-new "reset button as input button". No reset button. I like it though, mine runs a process that starts up the motors during short test runs of my latest bot.

Robots you can build in a weekend.

If you spend a weekend to do so, you can make a ROBOTIC BRAIN, which you then may "transplant" into various vehicles of propulsion. (ie: junk box r/c cars.)

This weekend project is so simple it`s what I would think of as a fundamental tool for robotics. We will create an assembly containing an IR detector subassembly and a motor-driving H-bridge.

Assembly is so simple it`s almost embarrassing.

You can build your own autonomous Robot by following the guidelines here. I like to think of them as guidelines, because it is your creative programming that will make this project most interesting.

I can get you started.

This project grew out of an idea I got when I found a couple of 2057 Giant LED Matrix`s. I thought it would be fun to make faces for robots that could monitor the bot like a piece of test gear that sat right on the bot.

I came up with a few ideas for dot matrix "faces" but it wasn`t just ultra-simple to wire in the matrices. They were designed to be driven row/column with the plus lines tied to column and the cathodes individually running out to pins on the display.

Blah... I put it away for a while. Till the other day when the M2 parts arrived to replace the 18X part I blew up while fiddling around. Hey! These 18M2`s are pretty amazing. You can find a robot project right here on this site, and other information on the 18M2.

My brain blasted when I realized as a consequence of being able to run four 4mHz processes at the same time, you could run one process at 4 X 4 16mHz. And the chip designers through in a treat, the setFreq m32 command. Now I had some speed, so I dragged out the 2057 and my soldering iron and went to work. The result is a dandy little 5X7 display that is crammed in behind the display so you could, if you wanted, stack `em in a message display.

Thus this project was born!

It is cool!
It is Cheap!

What a great project for CwhatIcanDo makers, hackers and circuit benders!

I bought a power wheelchair with the idea it was the best way to get cheap motors and a framework for a "big bot" that I could use to haul junk and do robot sorts of things.

My wife kept telling everyone I had a Power Chair - So I hurried up and put the thing under picAxe control, so my wife would now say I was working on a Robot - From a Wheelchair. Now it is an official Robot.

There is more to do. I want to make a set of sensors. And I want to make a remote control. I want it to be autonomous, but I want to tell it what to do, and let it figure out "how." Now I have the base unit under computer control, so all the rest is adding fun!

As situations would have it, I have installed and tested the unit with an IR Range Finder, simply by hooking up to the PC board already running the Power Chair.

From here I could install four sensors like this one, one at each corner, and as long as the speed was reasonably low, I believe the bot/power chair could navigate it`s way around fairly easily.

I believe I will do an experiment with sensors on the serial bus late, because I actually want to be able to remotely control the thing. I believe I want to take an existing remote controlled computer (that is programmable, of course) and use it to allow someone who is willing to hack their power chair, to be able to pull it up beside their car, or even drive it into a van on a ramp.

In the stories I hear, a simple inexpensive mechanism to give people a remote controlled chair would be a very big help to disabled power chair users everywhere.

Next stop: Wireless Remote Control!

Now that I spent some time "robotizing" a wheel chair, I felt I would like to do something with what I`ve learned about interfacing power chairs with control circuits.

This is my "Give Back" to handicapped people. While putting together a robot, I discovered I could use an H-Bridge to control the input to a differential drive robot, AKA "power-chair". This led to controlling a power chair with a simple microcontroller: "Building a Robot From a Power Wheelchair", this website.

Using the four wires from the joystick +, gnd, F/R, and L/R, I connected the output from an H-Bridge in an inexpensive Toy R/C Car through a pull-up, pull-down resistor (up down and Open) allowing independent two-channel control of a power wheelchair.

Making your own robots at home is not as wild an idea as you might think. Thinking about what you could "robot-ize" can get tricky. Here are some ideas and approaches.