Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What is the grid number for troy corser with under 22 laps?

### Inputs:
table_name: table, columns: ['Rider', 'Bike', 'Laps', 'Time', 'Grid']

### Response:
SELECT SUM Grid FROM table WHERE Rider = troy corser AND Laps < 22