To keep the WeDo simple and easy to use for younger children, the WeDo doesn’t have an intelligent brick in its building materials. No intelligent brick, so no programming and no power. The USB hub is there to provide both from the computer. But, wouldn’t it be great to be able to untether some WeDo creations? Well, it is possible. At least, it is possible to give WeDo creations power, if not programming. The key is to use elements from the Power Functions line of products. The Power Functions use exactly the same cables as the WeDo (and not the same as the NXT or EV3). So, by using one of the battery boxes, your WeDo creation has the power to propel itself beyond the reach of the computer. There’s are trade-offs though. As there is no programming, the sensors cannot be used. A programme cannot be written that controls how far the car will go. And, the battery boxes are large and heavy, necessitating some sophisticated building. This is not a project for grade one students. There are three battery boxes in the Power Function line.
The 8881 battery box is the heaviest and largest and takes six AA batteries. The smaller and lighter 88000 uses six AAA batteries. Finally, the 8878 is a rechargeable battery box that uses the same charger as used by the NXT and EV3 kits. In this photo, a car based on the design from [here] has been modified by removing the USB hub and adding in the battery pack. As there is only one switch on the 88000 and 8878, the car can only go in one direction. However, the switch on the 8881 allows you to power the car in two directions. Still not enough fun? Well, add in the 8869 Control Switch and controlling the direction (back and forth only) is now possible with the 88000 and 8878 battery boxes. But, the Control Switch will likely be built into the car as the cable is not very long. The ideal goal is remote control. Can the WeDo meet this challenge? The most fun might be using one of the remote controls with the 8884 IR Receiver. The 8885 and 8879 remote controls allow you to turn the motors (and lights) on and off.
In addition, the 8879 provides power level (speed) control as well. By using a two-motor design, it is even possible to have the WeDo car turn. Before rushing out to buy this equipment, check whether anyone has a Lego Train Set or Lego Technic Set that included Power Functions products. For this post, the 8293 Power Functions Accessory Kit was tested. This kit includes a motor, battery box, control switch, lights and a few building pieces. However, I then found out that my sons’ train set included the 88000 battery box, IR receiver and 8879 remote control. The following building guides were used as the basis of the cars featured in this post: Learning Sequence: LEGO WeDo Nine alternative programming languages for LEGO MINDSTORMSLinux Infrared Remote Control configuration files for LEGO Power Functions RC v1.20. - LEGO_Power_Functions_RC_v120 is a copy of LEGO's official documentation for their protocol. - LPF_RC_Protocol contains a summarized protocol definition and encoding/decoding timing parameters.
- LPF_RC_Modes contains summarized mode-specific data and deviations from the standard protocol. - LIRC_Remote contains common LIRC lircd.conf-style configuration file settings for the LEGO RC protocol. Compatible Hardware: 8884 IR Receiver | 8885 IR Remote Control | 8879 IR Speed Remote Control Referenced Documentation: LIRC Configuration File Format | LEGO Power Functions RC v1.20 Released under the MIT License. Speed Remote Control - $35 Power Function Speed Remote Control (8879) Remote Control - $29 Power Function Remote Control (8885) IR Reciever - $35 Power Function IR Reciever (8884) LEGO® is a trademark of the LEGO Group of Companies which does not sponsor, authorise or endorse this website, the MyBrick company or related products and services. Website Architecture by: D.D.DesignsToday LEGO Ambassadors received information about the long waited update, for the LPF RC Receiver and also the respective RC Protocol document.
Below, the official announcement from the Power Functions Product Manager (Gaute Munch). The LEGO Group has released a new version of the LEGO Power Functions RC Receiver (identified by a short blink on the green LED when power is connected). The new version of the RC Receiver supports all functionality of the LPF RC protocol and we have added a command to access the extra address space. We are hereby offering you an updated version of the LPF RC protocol documentation. Please feel free to use any information from the protocol document for personal, non-commercial use only, provided you keep intact copyright, trademarks and other proprietary rights of the LEGO Group. While not mentioned, the question now is to get confirmation whether: the previously detected failure about the 'single pin mode' was also fixed with this release or not? (expected but not yet confirmed) the new element will get a new product code? immediate orders of product 8884 to S@H, will be already dispatched with the new version of the affected element, or if there is still stock of the old element to exhaust?
...clarification request addressed to TLG. Meanwhile you can download the new LPF RC Protocol document (version 1.10). The product code is the same #8884 – the new item numbers are 4566735 (8884-1) and 4566756 (58123c01). Some time later it was found that the documentation originally released (version 1.10) was incorrect, and it was replaced by an updated document (version 1.20), which the one that describes the protocol implemented with the RC Receivers currently in production. TechnicBRICKs contents may be sporadically updated, if the authors finds further relevant info about a certain post, or content/spell mistakes. Hence please don't be surprised if you find few changes at later visits, relative to a previous read. TechnicBRICKs often shows other peoples' creations and/or images. We always try to credit the author(s) and link to their main publishing website, and if possible with their name in real life. Since this is not always possible, we request that if you find something here that is yours or from someone you know, you leave a comment on the respective post and claim the authorship.