4DOF Robot Arm

The robotic arm works and is easy to get going! Clearly this is more of a toy / learning kit, but it illustrates all the right features to start building larger projects. I was looking for a good Arduino robotics project to do with my child, and this product stood out. The majority of the arm came assembled (phew!), with the remaining assembly was easy and related more to the base and joystick. Wiring worked as expected, though I added a bit more length to the servo cables for the clamp servo (wires come with the kit for things like this). The product links to a long PDF manual that seems informative enough. Caveat: I've been programming Arduino's for a while, and it seemed easy enough to write my own code using the Servo library, so I did. The required code is not too complicated. I have yet to play with the bluetooth module, but I doubt it has issues. The PDF manual has code in it that I didn't try.

This was a fun kit to put together. It comes with some cool parts that can be re-used for other projects later, too. Specifically I like the included Arduino shield that allows control from a PS2 controller. Initially, I had the claw adjusted poorly, so it was hard to function, but I adjusted the screws and it worked well after that. The instructions do warn you not to over-tighten the screws, but I accidentally did anyway. There is included code (download) that allows for a memory function - move the arm and memorize position, then after you move it you can recall the position - such as dropping an item in a cup. Pretty fun! My kids really enjoy playing with this. I worked with them to put it together The included very tiny screws to connect to the servo horns were too small, however, there are extra screws that come with the servos themselves that work great for this purpose. There was not a link in the instructions to download the library for PS2 controller, but I was able to find it on github.

I bought this to start learning about Arduino as I am an electronics hobbyist. The instructions for this kit are terrible. The library they have you download does not work with Arduino IDE. After two days and endless searching and trying I have a hunk of aluminum with a flashing LED. And the only reason that works is because Arduino wrote that program. If you are looking for a place to start with Arduino stay very very far away from this kit. I hate this damn thing and am likely going to just toss it in the trash and avoid anything from Keyes after this

Nice little robot arm that you can build yourself. This is more than a remote control arm that you run from your phone. This kit is a learning experience. I particularly like the joystick handle that allows you to experiment with direct servo wiring and Arduino programming. You mount the two joysticks on an acrylic game-like controller, wire it to the Arduino type board, and go to it. Tons of screws and you have to go online for the manual, but once you have everything at hand you are ready to start. Take your time adjusting the motors and examining the assembly pictures, and everything goes together smoothly. When you have completed the included projects, there is great opportunity to experiment with other projects of your own. There is also a way to control the arm via Bluetooth (this means using your Android or Apple phone) or even a PS2 JoyStick controller. If you tire of experimenting with servos you can always remove the arm shield and have full access to the Arduino pins. Just add a few sensors continue exploring.

I’ll start with the wiki. The arm comes with a parts list in the form of a pamphlet within the box. There is a QR code on this that will take you to the Keyestudio wiki and on this page you will find a search bar. I believe I searched something like “4DOF Arm Kit” and some suggestions came up (make sure you select the V2 instructions). Very cool little robot arm, the provided code works great and if everything is plugged in correct; runs flawlessly. The “arm” unit comes preassembled so you’re basically just going to be attaching that to a base you put together and coding it to work. Biggest problems are the weird 18650 batteries you’ll need to get to use the provided battery pack. This is one of those devices that will do WEIRD things when undersupplied (like whip or spin around all crazy) These batteries are 4.8V-5V rechargeable batteries (so a 9v battery won’t do if you want to drive all 4 motors simultaneously) I also ran into trouble with the servos; after 3-5 minutes of use (only occasionally being driven) they started seizing up and about 2 days later I have only 1/4 servos still working. (the others spin freely in the casing and get very hot but do not actuate the gears inside anymore.) Hard to say if this is standard quality control or if this was the weird 18650 batteries frying my servos *shrug* either way; learned a lot and have a lot of questions I’d like to go find the answers to. Final thoughts: if you were going to order this, consider picking up some extra metal geared servos and 18650 batteries or a suitable replacement battery pack. **UPDATE** Replaced the 3 broken servos with new motors. Works great now. My base servo has a little “Jig” to it (visible in the video, this is the only keyestudio servo still on the bot so these servos must not have great QC). Link to replacements I used included below. They all work and fit the build. The final tip I can give you is to make sure to test all your servos actuation between 0-180 before running this thing. Specifically the forward and back and up and down servos are placed in such a way that they are sometimes in competition if not installed correctly which will break them. All in all: 4/10 on difficulty for most people, 3/10 on quality of included parts, and 5 stars because this was all very fun. (https://www.amazon.com/MG90S-Servo-Motor-Helicopter-Arduino/dp/B01JY3H4MA/ref=mp_s_a_1_2_sspa?keywords=9+gram+metal+gear+servo&qid=1659280156&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFLOFMxQjZJRjEzVUcmZW5jcnlwdGVkSWQ9QTAxNTQ4ODhJNE5WUElWRkdKSVYmZW5jcnlwdGVkQWRJZD1BMDU5NTkxNDJLNVVLN1I3MzJYUlgmd2lkZ2V0TmFtZT1zcF9waG9uZV9zZWFyY2hfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==)

Kit was well packaged and all parts accounted for. Installation requiring usng Keyestudio web page. Find the WIKI for DoF Robot Arm Kit V2.0 for Arduino. This WIKI will provide you with assembly, witing and operational codes for your Robot Arm. There is also a KS0488 page on the web page that shows the detailed assembly of the CLAW of the 4DoF arm itself. (I found these pages very useful) Assembly: As per earlier reviews, do not tighten the lock nuts too tight. They can be adjusted later on if too loose. Follow the wiki and should have no problems. (see below) I ran mot of the tests and found the code accurate. It would help if you had experience in Arduino code structure. Comments: The lock-nuts are very tight so be careful not to strip the heads of the screws. Make sure the teeth of the Jaws, left and right are properly meshed before completing assembly. The product is well manufactured with aluminum for the cranes and solid plastic for the bases. Young children will certainly need the help of an adult to assemble but adults may need help from their children to code??

まずパッケージが綺麗でしたので、写真付で。 この手のキットはパーツリストすら提供されていない物が見受けられるのですが、これはパーツリスト添付。しっかりチェック出来ました。 組立の説明書はオンライン供給ですが、添付されていた書類記載のQRで飛んでも目的のページには行けませんでした。検索方法が書かれているので、その手順に従って探す必要有りです。説明書の記述はとてもわかり易いものでした。 組立時には、サーボの角度調整等を行なうのでarduinoへのプログラム書込みが伴います。要PC(windows機)ですね。これは販売ページに書いておくべきだと思いますが。 arduino統合環境を使った事が無い人には若干敷居が高いかも知れませんが、ググれば初心者向けの解説は沢山有るので、心配無いでしょう。 …さて、組み立ててみるか。 ヤスリが必要有りでした。サーボ取付ブラケットの取付穴が若干狭く、削ってやらないと取り付けられませんでした。 長手方向の縁をごく僅か(0.1mm程度かな）削ってやる必要がありました。 また、付属のドライバーは先が小さいので、M3ネジを締めるのは厳しいですね。#2ドライバーを用意しておくと吉でしょう。 最大の問題は電源かな。USB給電ではarduino へのプログラム書き込みしか出来ません。キットは18650バッテリーを2本使用する事を前提にしているのですが、保護回路も無しでリチウム電池を使うのはちょっと怖い。充分な容量を持った7~9VのACアダプターを接続するのが良いかと思います。 まとめておきます。 別途必要な物： ・電源(7~9V)←2A以上は欲しいかな…(追記：5Vで行けました） ・ヤスリ ・#2プラスドライバー 追記： あまりにも基本的な事で忘れていましたが、ラジオペンチが有った方が組み立ては楽です。結構大量にロックナットが使われていて、付属のスパナはサイズ違いのために使用不可でしたので。 また、インターフェース基板の仕様が不明でしたので、サポートに問い合わせしてみたのですが、とんちんかんな回答が返って来ました。（笑） アテにはならなさそうですが、レスポンスは速かったので、くじけずに何度か連絡すれば求める答が得られるかも知れない…と言った感じで行くと良さそうです。 9/29追記： ３回質問して、拡張ボードの回路図を送って貰えました。回路図を信頼するなら、ボードに供給する電源は12v程度まで大丈夫ですね。ただし、使用されているコンデンサの値が回路図記載の容量より小さい(多分、コストカットのために他の物と同じ容量にしたんでしょう)など、信頼しきれない部分は有りますが。まぁ、配線パターンは変更していないだろうから、多分大丈夫かと。

There are plenty of kits available on Amazon, but not all of them include the little tools like the screw driver, cable protection, and full instructions. Yes, full, including drivers and a (working) app. The arm actually came semi assembled, so if you want the full experience you've gotta undo that first. Oh and by "PS2 controller" it means a literal Sony PS2 controller, not a windows controller with a PS/2 plug.

マニュアルやプログラムのダウンロードに、時間が掛る。

Un beau petit projet pas bien chère pour passer une hiver longue, pas trop compliqué mais il faut être débrouillard, les instructions sont quand-même bien.