This proposal aims to open the bi-directional HRMP channel between [Robonomics](https://robonomics.network/) and Statemine. It is based on similar processes for [Karura](https://kusama.polkassembly.io/referendum/163), [Moonriver](https://kusama.polkassembly.io/referendum/164), [Basilisk](https://kusama.polkassembly.io/referendum/172), [Parallel Heiko](https://kusama.polkassembly.io/referendum/188) and [Bifrost](https://kusama.polkassembly.io/referendum/165).

### Technical Details

The proposal is to execute a batch transaction with two calls:

1. A force transfer (`balances.forceTransfer`) of **11 KSM** from Kusama Treasury (`F3opxRbN5ZbjJNU511Kj2TLuzFcDq9BGduA9TgiECafpg29`) to Statemine (`F7fq1jSNVTPfJmaHaXCMtatT1EZefCUsa7rRiQVNR5efcah`) to pay for fees accepting the channel request. 10 KSM will be used for deposit to accept (**5 KSM**) and open (**5 KSM**) HRMP channel. **1 KSM** will be used by Statemine parachain to pay for transaction execution fees on Kusama.

2. Sending XCM message (`xcmPallet.send`) to Statemine to execute a transaction with superuser (root) permission.

Preimage design can be reviewed [here](https://drive.google.com/file/d/1cby2EkC0EiHeK1hNhgIN-4ymTdJVhsCZ).

Encoded call hash:

`0x7d9b45ceab82d52ee5d04357225bcb9a5a7ce3ed04c01b926dec23f3c78f77aa`

Encoded call data of this batch transaction, which can be decoded on Kusama:

`0x1802080402006d6f646c70792f747273727900000000000000000000000000000000000000000070617261e80300000000000000000000000000000000000000000000000000000b00b01723010a630001000100a10f020406020300943577a9011f000101000214000400000000070010a5d4e81300000000070010a5d4e800060002286bee5c1802083c01000800003c0000080000e803000000900100140d01010000000004000101006d6f646c70792f74727372790000000000000000000000000000000000000000`

### XCM message

The XCM message that is sent to Statemine looks like:

`0x1f000101000214000400000000070010a5d4e81300000000070010a5d4e800060002286bee5c1802083c01000800003c0000080000e803000000900100140d01010000000004000101006d6f646c70792f74727372790000000000000000000000000000000000000000`

The message can be decoded on Statemine. It consists `polkadotXcm.send`, which sends a XCM message back to Kusama to perform `Transact` of this call:

`0x1802083c01000800003c0000080000e803000000900100`

which can be decoded on Kusama. This call is a batch transaction with two calls: the first one accepts the open channel request (`hrmp.hrmpAcceptOpenChannel`) from Robonomics (ParaId: 2048), and the second one to make a reciprocal open channel request (`hrmp.hrmpInitOpenChannel`) to Robonomics.

After Transact, it follows up with `RefundSurplus`, which refunds any unused weight from execution, and then `DepositAsset`, which instructs the executor to deposit any KSM that wasn't used on transaction fees back into Kusama Treasury.

Preimage design of the XCM message can be reviewed [here](https://drive.google.com/file/d/1RBONNqCXjTDfpDh4W9nXPa2BQtD8Kqf7).

Preimage design of the a batch transaction for accepting/requesting can be reviewed [here](https://drive.google.com/file/d/127jr8HDlHsTxRbx7d4WdRJbwrTO-hDdb).

Send a batch of dispatch calls and atomically execute them.
The whole transaction will rollback and fail if any of the calls failed.

May be called from any origin.

- `calls`: The calls to be dispatched from the same origin. The number of call must not
  exceed the constant: `batched_calls_limit` (available in constant metadata).

If origin is root then call are dispatch without checking origin filter. (This includes
bypassing `frame_system::Config::BaseCallFilter`).

# <weight>
- Complexity: O(C) where C is the number of calls to be batched.
# </weight>

- This proposal is about opening a channel between two platforms called Robonomics and Statemine.
- The proposal suggests a technical process involving transactions and messages.
- The proposal includes details about the amount of KSM (a type of cryptocurrency) that will be transferred.
- There are links provided for more information about the technical aspects of the proposal.
- The proposal aims to improve communication and transactions between Robonomics and Statemine.

#207 Open HRMP Channel Between Robonomics and Statemine