Congratulations on your purchase of the SR-RH5D and/or SR-RH7D Hand. This hand is the result of years' experience in hand design and use and it aims at incorporating everything a robot builder needs: reliability^3, ease of use and compatibility with existing robot platforms in both hardware and software.

NOTE: The RH5D and RH7D have the same external dimensions and design and use the same internal electronics. For this reason, documentaiton for both is combined.
The difference between the RH5D and the RH7D is that the RH5D does not have Wrist Adduction and Wrist Flexion capacbility. Those two Degrees of Freedom are locked and the corresponding motors for actuating them are not installed.

Package Contents

When unpacking, please check your package contents. The set of spares varies depending on whether your purchased a single hand or a pair.

For a single hand

  • 1x SR-RH5D or SR-RH7D Hands (depending on your order)

For a Pair of Hands

  • 2x SR-RH5D or 2x SR-RH7D Hands (1x Left and 1x Right), depending on your order

Note: The Bluetooth interface and Capacitive Pads, if ordered, are installed inside the unit. They will not be visible from the outside.

If your ordered the PC Interface Board + Power and Data Hub + Power Supply

  • 1x Power Supply 12V
  • 1x USB to Serial converter cable. \\Typically, this will be a special 2-in-1 cable with miniaturized circuitry built inside the USB connector.
  • 1x Power and Data Hub board
  • 1x or 2x Long connection cable (depending on whether you ordered one unit or a pair or units)
  • 2x Short connection cables

The Long and Short connection cables are similar and can be interchanged if the user needs. The Long cable is usually used to connect to the main unit but this is not mandatory; any of the cables can be used.

Assembling the unit on your Robot: Overview

The hand is assembled by means of 4-6 screws located on the back (“wrist”) position. These screws are designed with common spacing in mind, being compatible with assembly on Darwin-OP/Robotis OP2 (for OP assembly instructions, see below).

Assembly screws are already pre-assembled (in green). Remove them, including the washers. Pay attention to NOT remove the screws in red or any other screws and they are structural to the hand assembly.

To prepare the assembly, align parts as seen in the next picture (here we show a sample bracket).

The wrist rotation has approximately 180º of range. Therefore, for correct assembly, rotate central hub in the direction marked in the picture according to the side on which you are assembling: left hand or right hand. ( To rotate the central hub you can use one of the hex keys inserted in the central screws. )

If you are Assembling on Darwin-OP / Robotis OP2, the assembly screws are to be assembled through the holes marked in blue. (the frame shown is from the OP robot).


  • When tightening screws do not push them in. Screws should be tightened by rotation only.
  • Use the included screws for installing your unit, whenever possible. These were selected to provide an appropriate length without interfering with any of the internals. If you need to use screws with different length, our support team can assist you in determining the best length so that they won't interfere with any of the internals.

At this point it is strongly recommended that you test the range of rotation of the gripper by turning them manually or ideally by turning the unit on and moving it in software.

If adjustment is needed remove the assembled screws, rotate gripper to next available position and re-attach screws.

BEST PRACTICE: we suggest applying thread lock glue (included in your Darwin/Robotis OP[2] kit) to the screws holding the hand.

Complete the assembly by connecting a Dynamixel cable from the hand to the nearest interface (servo or PC adapter).

Copyright © 2015-2020 Seed Robotics Ltd

  • rh7d/unpacking_mechanical_assembly.txt
  • Last modified: 2019/02/20 09:26
  • by pedro.ramilo